# News Highlights
Source: https://docs.blockscout.com/about/announcements

News, media coverage, and major announcements related to Blockscout.

## Seed Funding Announcement

<Card title="Blockscout Raises $3M Seed Round Led by 1kx" href="https://www.blog.blockscout.com/blockscout-raises-3m-seed-round-led-by-1kx/">
  Blockscout open-source explorer
</Card>

## OurNetwork Blockscout Feature

OurNetwork is a leading crypto publication providing data-driven insights on blockchain industry trends. This deep dive on Blockscout features coverage about Blockscout Network Health, User Trends, Explorer-as-a-Service, and the DAppscout Marketplace.

<Card title="ON–286: Zoomed-in on Blockscout 🔬" href="https://www.ournetwork.xyz/p/on-286-zoomed-in-on-blockscout">
  OurNetwork
</Card>

## Dappcon 2024 Blockscout Presentation

Head of research Kirill Fedoseev presented on network resilience and the need for reliable, transparent, and available explorers in a multi-chain world (starts at 7:50:00)

<Frame>
  <iframe title="DappCon24: Day 3 - Consensus Layer" />
</Frame>

## EthCC 2023 Blockscout Presentation

Head of Product Ulyana Skladchikova presented on the future of block explorers at ETHCC 2023 in Paris.

<Frame>
  <iframe title="Ulyana Skladchikova - Envisioning tomorrow: Evolution of blockchain explorers" />
</Frame>

## The Evolution & Future of Infrastructure at Optimism's On-Chain Summit

<Frame>
  <iframe title="Onchain Summit: The Evolution & Future of Infrastructure" />
</Frame>

## Base + Blockscout mainnet launch announcement

<Card title="Base Block Explorer Blockscout" href="https://www.blog.blockscout.com/blockscout-base/">
  Blockscout open-source explorer
</Card>

## Base + Blockscout original press release

<Card title="Base Open Source Block Explorer.pdf" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2FdzWTqaTgnhWRkD40C3Ay%2FBase%20Open%20Source%20Block%20Explorer.pdf?alt=media&token=7a6edb78-e9cd-4e85-91d8-13d6d08db3e5">
  pdf
</Card>


# Newsletter & Blog
Source: https://docs.blockscout.com/about/announcements/newsletter-and-blog



The Blockscout Newsletter is sent out bi-monthly. It includes information on updates, new chains, integrations and other related information. If you use the My Account feature on Blockscout, an email newsletter subscription is automatically enabled when you sign up. You can unsubscribe at any time by clicking the unsubscribe link at the bottom of the email.

<Icon icon="flag" /> You can also [subscribe to receive the newsletter](https://www.blog.blockscout.com/).

<Icon icon="flag" /> Past newsletters are available on the [Blockscout Blog](https://www.blog.blockscout.com/).

<Frame>
  <img alt="Blockscout Newsletter image" />
</Frame>


# Chains Using Blockscout
Source: https://docs.blockscout.com/about/chains

List of projects and links

<Warning>
  **The new searchable projects page is located at [https://chains.blockscout.com/](https://chains.blockscout.com/)**

  **Please [Submit a PR](https://github.com/blockscout/chainscout) to add your chain.**
</Warning>

<Frame>
  <img />
</Frame>


# Features
Source: https://docs.blockscout.com/about/features

Blockscout is a full-featured, open-source blockchain explorer

<Check>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. **[Get Started Now](/using-blockscout/autoscout) and have your explorer up-and-running in minutes.**
</Check>

### What can I do with Blockscout?

* **Deep Search**: Find all the information you need on [Blocks](/using-blockscout/overviews/blocks), Transactions, Addresses, Tags and more through the integrated search box.

* **Interact with Contracts**: [Read and write to contracts](/devs/verification/interacting-with-smart-contracts) directly from the Blockscout UI.

* **Verify Contracts:** Use [Hardhat](/devs/verification/hardhat-verification-plugin), [Sourcify](/devs/verification/contracts-verification-via-sourcify), and other tools to quickly verify contracts.

* **Make API Calls**: Make requests to a [robust API](/devs/apis) using standard and customized endpoints.

* **Customize Views**: Use the [My Account](/using-blockscout/my-account) features to add tags, watchlists and other features.

* **Interact with Apps**: Chains with the [Apps Marketplace](/using-blockscout/blockscout-apps) enabled include a portal for discovery and interaction with applications deployed on-chain.

### Key Features

* **Open source development**: The code is community driven and available for anyone to use, explore, and improve.

* **Broad multi-chain ecosystem support**: Blockscout supports Ethereum mainnet, EVM forks like Ethereum Classic & Gnosis Chain, the Superchain Ecosystem, Polkadot Parachains, Cosmos ecosystem, and many additional public and private EVM networks. [See the list](/about/chains)

* **Smart contract interaction**: Users can read and verify Solidity & Vyper smart contracts and access pre-existing contracts to fast-track development.

* **Token support**: Support for ERC20, ERC721 and ERC1155 tokens.

* **Decoded views:** Contract method calls and logs are decoded to provide additional information within the UI.

* **Full-featured API:** GraphQL provides the opportunity to test API calls directly from a web interface, and REST and JSON RPC methods are well documented.

* **User customization**: Users can easily deploy on a network and customize the Bootstrap-based interface.

* **Modular and extendible**: We're building next generation modularity into Blockscout with Rust-designed microservices.


# Funding
Source: https://docs.blockscout.com/about/funding

Information about Blockscout funding sources, grants, and opportunities for support.

Blockscout [raised their first seed round](https://www.blog.blockscout.com/blockscout-raises-3m-seed-round-led-by-1kx/) in 2024 to help bring open-source exploration to more blockchain users.

We would like to thank projects, individuals, and agencies who have helped support Blockscout open-source explorer growth either through direct giving or grants to support instances.

We are open to additional grant opportunities and [welcome queries](https://discord.gg/XmNatGKbPS) from projects in need of a new open-source explorer instance or maintenance of their current instances.

Funding grants include:

* Seed Grant from the [Ethprize Foundation](http://ethprize.io/) (2018)

* [Gitcoin Grants](https://explorer.gitcoin.co/#/round/424/0x222ea76664ed77d18d4416d2b2e77937b76f0a35/0x222ea76664ed77d18d4416d2b2e77937b76f0a35-22) rounds (ongoing)

* [Community governance funding from Astar](https://forum.astar.network/t/blockscout-builders-program-application/1735) to support Blockscout instances for their networks (2021)

* [GnosisDAO funding](https://forum.gnosis.io/t/gip-54-should-gnosisdao-support-hosting-and-feature-updates-for-blockscout-explorer/5378/4) to support Gnosis Chain Blockscout instances (ongoing)

* [Optimism RetroPGF2](https://optimism.mirror.xyz/Upn_LtV2-3SviXgX_PE_LyA7YI00jQyoM1yf55ltvvI) & [RetroPGF3](https://optimism.mirror.xyz/37Bgum6MfTJWDuE41CH9RXSH5KBm_RCL5zsSFeRZl4E) (2023)

* [ETC Grants DAO](https://etccooperative.org/posts/2023-08-09-presenting-first-round-etc-grants-dao-winner-blockscout-en) (2023)

* Grant support from the [Ethereum Foundation](https://ethereum.foundation/) (2023 & 2025).


# Partners & Integrations
Source: https://docs.blockscout.com/about/partners-and-integrations

Blockscout featured integrations

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  <img />
</Frame>

Blockscout features many 3rd party integrations. Additional services are also integrating Blockscout, including many [Rollup-as-a-Service (RaaS) providers](/about/partners-and-integrations/raas-providers).

## Blockscout Partners

Partners provide vital data, infrastructure, and contract support to Blockscout.

|         |                                                                                                                                                                                                                                                                                                     |
| ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**Metasuites**](https://blocksec.com/metasuites) by Blocksec provides an browser extension that enhances Blockscout with address labelling, transaction explanations, and compliance scores for addresses based on behavior.                                                                       |
| <img /> | [**Sourcify**](https://sourcify.dev/) gives developers the option to verify contracts via the Sourcify API with Blockscout. Contracts verified through Sourcify will display this information on the verified contracts page. [Learn more](/devs/verification/contracts-verification-via-sourcify). |
| <img /> | [**DPRC**](https://drpc.org/) is a decentralized Web3 infrastructure provider with a focus on resilience and latency. DPRC provides RPC services for a number of Blockscout hosted instances.                                                                                                       |

## Tools and Utilities

Blockscout provides links to relevant, useful tools related to specific transactions and contracts for easy enhanced inspection.

|         |                                                                                                                                                                                                                                                                                                           |
| ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**Tenderly**](https://tenderly.co/) is an all-in-one Web3 development platform. It is extremely useful for transaction simulation and smart contract development. Blockscout provides a link to transactions for viewing additional detailed information on the Tenderly platform.                       |
| <img /> | [**Sentio**](https://www.sentio.xyz/) is a monitoring, alerting, log management and debugging service for blockchains. Blockscout provides a link to the Sentio explorer for users who need to find advanced analytics about a particular transaction or contract, and read/search/write/fix code faster! |
| <img /> | [**SolidityScan**](https://solidityscan.com) is an AI-driven tool specifically tailored for Smart Contract Vulnerability Detection within the web3 ecosystem. With the Blockscout integration, users can access a real-time security score for verified contracts on supported chains.                    |

## Linked Explorers

Blockscout includes links to additional blockchain explorers for verification and transparency on hosted instances. Self-hosted instances can choose which additional explorers to link with using [front-end ENVs](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md) during deployment.

|         |                                                                                                                                                                                                                                                                                               |
| ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**Blockchair**](https://blockchair.com/) block explorer indexes data for 18 blockchains. When available, Blockscout provides a link to Blockchair for transactions, addresses, and more so users can verify and double-check data accuracy.                                                  |
| <img /> | [**Etherscan**](https://etherscan.io/) explorer is available for large chains and provides a comprehensive data source. When available, Blockscout provides a link to Etherscan so users may double check and verify transactions on multiple explorers.                                      |
| <img /> | [**0xPPL**](https://0xppl.com/) offers social search as well as transaction information, providing a connection between on and off chain data. When available, Blockscout provides a link to 0xPPL for transactions, addresses, and more so users can verify and find additional information. |
| <img /> | [**3xpl**](https://3xpl.com/) is a fast, universal explorer for most popular public blockchains. When available, Blockscout provides a link to 3xpl for data verification.                                                                                                                    |

## Contract Verification

Contract verification integrations make it easier to verify contracts from a variety of development environments and bring in additional verified contract information.

|         |                                                                                                                                                                                                                                                                      |
| ------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**Hardhat**](https://hardhat.org/) is a popular Ethereum development environment. Contracts can be deployed and verified on Blockscout using the verification plugin. [Learn more](/devs/verification/hardhat-verification-plugin).                                 |
| <img /> | [**Foundry**](https://github.com/foundry-rs/foundry/) is a smart contract development toolchain and Forge is a command-line tool that ships with Foundry that supports contract verification with Blockscout. [Learn More](/devs/verification/foundry-verification). |
| <img /> | [**Remix**](https://remix-project.org/)is a popular IDE for developing smart contracts. You can use the built-in verification plugin to verify contracts in Blockscout. [Learn More](/devs/verification/remix-verification).                                         |
| <img /> | [**Sourcify**](https://sourcify.dev/) is an open-source platform for verifying contracts. You can use the Sourcify API to verify contracts in Blockscout. [Learn more](/devs/verification/contracts-verification-via-sourcify).                                      |

## Tokens and TVL

Feeds can be sourced from several options to provide the latest up-to-date token information. These options are set through [application ENVs](/setup/env-variables) during deployment.

|         |                                                                                                                                                                                                                                                                                       |
| ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**CoinGecko**](https://www.coingecko.com/)is a source for token prices and market cap information using the e CoinGecko API. CoinGecko is a leading application which provides price tracking, volume and market capitalisation, community growth, and open-source code development. |
| <img /> | [**CoinMarketCap**](https://coinmarketcap.com/) is a source for token prices and market cap information using the CoinMarketCap API. CoinMarketCap is a popular price-tracking website for crypto assets.                                                                             |
| <img /> | [**Cryptorank**](https://cryptorank.io/) provides data aggregation and analytics services. The application tracks crypto assets, prices, and detailed information about cryptocurrencies.                                                                                             |
| <img /> | [**Mobula**](https://mobula.io/) is a crypto data aggregator that provides curated blockchain data and industry-leading coverage.                                                                                                                                                     |
| <img /> | [**CoinCompare**](https://coincompare.eu/) is a source for token prices using the CoinCompare API. CoinCompare is a real-time crypto price tracker and comparator.                                                                                                                    |
| <img /> | [**Trust Wallet**](https://trustwallet.com/) is a source for token icon information. Trust Wallet is a leading self-custody multi-chain platform, we support millions of assets across 100+ blockchains.                                                                              |
| <img /> | [**DeFiLlama**](https://defillama.com/) is a source for TVL information through the API integration. DeFiLlama is a DeFi TVL aggregator providing accurate and transparent data.                                                                                                      |

## Ad Providers

Ad providers can be selected to bring relevant, web3 based ads based on the network where Blockscout is deployed. Ad options are set using [front-end ENVs](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md) during deployment.

|         |                                                                                                                                                                                |
| ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| <img /> | [**Slise**](https://www.slise.xyz/) specializes in web3 ads for users featuring transparent data usage and no tracking. It is the default ad network for hosted chains.        |
| <img /> | [**Coinzilla**](https://coinzilla.com/) is a large ad network for crypto-relevant content and are well-established in the blockchain space.                                    |
| <img /> | [**Adbutler**](https://www.adbutler.com/) provides ads for many different types of industries and users, and can be a good option for instances that serve diverse user bases. |


# RaaS Providers
Source: https://docs.blockscout.com/about/partners-and-integrations/raas-providers

Rollup-as-a-Service Providers using Blockscout

<Frame>
  <img />
</Frame>

Many Rollup-as-a-Service providers are using Blockscout as the default explorer for their instances. Once deployed, Blockscout can provide explorer support services when rollups want to customize or augment their explorers.

Each RaaS has their own processes and specializations including zkRollups or opRollups optimized for different environments. If you have questions about which RaaS to choose, or need customizations for your RaaS Blockscout instance, [please contact us and we can direct you to the best option for your chain](https://www.blockscout.com/#contact-us).

|         |                                                                                                                                                                                                                                                                                                          |
| ------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <img /> | [**Gelato**](https://www.gelato.network/): Gelato's zkRollup as a Service Platform is fully-serviced, leverages OP, Arbitrum Orbit and Polygon zkEVM, and provides High TPS, Low Fees, and Ethereum's Security.                                                                                          |
| <img /> | [**Alchemy**](https://www.alchemy.com/): Alchemy is a proven web3 infrastructure provider now offering best-in-class RaaS services for L2s and L3s.                                                                                                                                                      |
| <img /> | [**QuickNode**](https://www.quicknode.com/rollup): QuickNode offers enterprise-grade rollups backed by industry-leading infrastructure. Supporting Optimism Superchains, Arbitrum Orbit Chains, and ZKsync Elastic Chains. [Docs](https://www.quicknode.com/docs/rollups/intro)                          |
| <img /> | [**Conduit**](https://conduit.xyz/): Conduit's RaaS platform allows teams to scale their applications quickly and easily using production-grade OP Stack or Arbitrum Orbit rollups.                                                                                                                      |
| <img /> | [**Zeeve**](https://www.zeeve.io/): Low-code, scalable, enterprise-grade infrastructure for ZK Rollups and OP Stack Rollups.                                                                                                                                                                             |
| <img /> | [**Caldera**](https://caldera.xyz/): Caldera makes it easy to launch high-performance, customizable, and application-specific Arbitrum Orbit and OP Stack rollups.                                                                                                                                       |
| <img /> | [**Aurora Cloud**](https://auroracloud.dev/): Aurora Virtual Chains are EVM compatible blockchains inheriting the full security, scalability and infrastructure of Near Protocol                                                                                                                         |
| <img /> | [**Lumoz**](https://lumoz.org/?ref=blog.blockscout.com): Lumoz offers an easy-to-use, universal launchbase where anyone can quickly create a zk-rollup with several different options. [Learn More](https://www.blog.blockscout.com/lumoz-and-blockscout-collaborate-to-elevate-the-zk-raas-experience/) |
| <img /> | [**Presto**](https://gateway.fm/presto/?ref=blog.blockscout.com): Presto provides zk-Validium and zk-Rollups with instant deployment and a full suite of tools. Settle on Eth or Gnosis Chain. [Learn More](https://www.blog.blockscout.com/blockscout-presto-raas/)                                     |
| <img /> | [**Altlayer**](https://altlayer.io/raas): Altlayer offers a versatile rollup stack including Arbitrum Orbit, OP stack, Polygon ZKEVM and StarkWare, and support for various DA layers such as EigenLayer and Celestia.                                                                                   |
| <img /> | [**Chainstack**](< https://chainstack.com/>): Chainstack provides infrastructure services including rollup deployment.                                                                                                                                                                                   |
| <img /> | [**Snapchain:**](https://www.snapchain.dev/) Snapchain specializes in zkRollups for scaling on-chain games and DeFi applications cheaply and securely.                                                                                                                                                   |
| <img /> | [**Dymension**](https://dymension.xyz/): Dymension offers app-chains called RollApps, designed for application-specific speed and efficiency.                                                                                                                                                            |
| <img /> | [**Vistara**:](https://www.vistara.dev/) Vistara provides a one-click rollup deployment framework for designing and managing scalable infrastructure.                                                                                                                                                    |


# Vera: Verifier Alliance
Source: https://docs.blockscout.com/about/partners-and-integrations/vera-verifier-alliance



<Frame>
  <img />
</Frame>

The [Verifier Alliance](https://verifieralliance.org/) is an ecosystem collective aiming for easy, unified, and open access to the source-code of EVM smart contracts. It is made up of projects across the ecosystem dedicated to making source code verification information freely available for all. Blockscout is a founding member of the collective and major contributor to the Vera Database.

* [Blockscout Vera app](https://vera.blockscout.com/): Verify and Publish contracts to supported networks.

* [Add your network to the Vera DB](/about/partners-and-integrations/vera-verifier-alliance/adding-your-chain-to-the-vera-database)

* [Verify contracts programmatically via the API](/about/partners-and-integrations/vera-verifier-alliance/programmatic-verification-via-the-api)


# Roadmap
Source: https://docs.blockscout.com/about/roadmap

Upcoming enhancements, features, and strategic plans for Blockscout.

# Roadmap

<Info>
  The Blockscout roadmap is a high-level strategic plan designed to guide research and development. **Target dates and details are reviewed by the team and subject to move, adjust and change as the project evolves**. Note that only completed items (✅ Status: Complete) are considered achieved project milestones.

  [*Last update: SEP 2025 | Changelog*](/about/roadmap#change-log)
</Info>

## 🟦 Q3-4 2025

We've updated our roadmap for the remainder of 2025 with a focus on our flagship auto-launch platform Autoscout.

<AccordionGroup>
  <Accordion title="⭐️ Autoscout" description="Includes 2025 & Q 1-2 2026 Roadmap">
    **2025**

    * **Plugin system:** Create basic plugin system for self-deployed chains
    * **User ops plugin**: First plugin launched for user ops
    * **Recurring payments**: Build out recurring payments system for regular users

    **2026**

    ***Q 1-2***

    * New Plugins:
      * **Admin panel**: Instance can access to admin functionality
      * **Account Features**: Instances can add MyAccount to provide user-centric features such as tags and API key generation
      * **BENS (ens resolution)**: Instances can add support for ENS names.
    * **Automatic scaling**: Will provide real-time scaling as needed to support large spikes or decreases in usage.
    * **DDoS protection**: Improve security and reduce potential slowing from DDoS attacks
    * **Setup wizard** (get setting from RPC URL): Simple setup for new instances
    * **Background RPC validation**: Will improve monitoring and alerts
    * **Password protection**: Instances can protect new instances before they go public.
  </Accordion>

  <Accordion title="⭐️  AI integrations">
    * MCP server integrations, improve MCP service and expand usage
    * Explore basic chat integration with instances
    * Chat integration with DeFi products such as Swap
  </Accordion>

  <Accordion title="⭐️ Universal Bridge Indexer">
    * Index cross-chain bridge transactions
    * Create UI interface for exploration
    * Targeting Gnosis Chain as the first live instance
  </Accordion>

  <Accordion title="⭐️ PRO API">
    * PRO API service with higher limits and additional endpoints
    * Create self-service module
  </Accordion>

  <Accordion title="⭐️ Essential Dapps">
    * Design integrated interface and move current standalone Blockscout DeFi apps (Swap, Revoke) to Essential Dapps within the explorer
    * Add Multisender app to Essential Dapps
  </Accordion>

  <Accordion title="⭐️ Custom Dev">
    * Continued development for customized instances
    * Based on client needs on a chain-by-chain basis
    * Support new and upcoming features on hosted chains
  </Accordion>

  <Accordion title="⭐️ Data Services">
    * Create data service with wide instance coverage.
    * Custom data delivery for a wide range of real-time and historica data.
      * Contract and protocol deployment tracking and ecosystem analysis
      * Cross-chain liquidity movement and large asset flow monitoring
      * Public address labeling and protocol identification
      * Dapp interaction and dapp usage reports
  </Accordion>

  <Accordion title="⭐️ Analytics and Statistics">
    Smart Contract Analytics

    * Provide detailed analytics for smart contract usage and performance

    Advanced EOA (Externally Owned Account) Analytics

    * Offer in-depth analysis of regular user accounts

    Market Data Integration

    * Incorporate relevant market data into the explorer

    Protocol-specific Stats

    * Provide statistics broken down by different protocols
  </Accordion>

  <Accordion title="⭐️ NFT Explorer Features">
    * Display top NFTs
    * Show latest trades, transfers, and mints
    * Integrate with NFT marketplaces and platforms
  </Accordion>
</AccordionGroup>

## 🟦 Q1-2 2025

We accomplished many important updates in the first half of 2025. Any items not completed have been either restructured or moved to Q3-4.

### ✅ Account Abstraction

**Target Date:** Q2 2025

* Support for AA transaction actions: Improved handling of AA-specific transactions
* Public tags for Bundlers, Paymasters, Factories: Better identification of AA-related accounts

### ✅ Advanced Features

**Target Date:** Q2 2025

Includes:

* Multi-chain Search: Allows users to search across multiple blockchain networks simultaneously
* Advanced Filters Enables more detailed and customizable data filtering options
* Export Filter Results to CSV Allows users to download filtered data in CSV format for further analysis
* Validators Page Displays information about validators for Proof-of-Stake chain chains
* Simplified Account Creation Integration with WalletConnect for easier account setup

### ✅ Analytics and Statistics

**Target Date:** Q1 2025

* Customizable Time Views: Daily, weekly, monthly, and yearly data views

### ✅ Defi Integrations

**Target Date:** Q2 2025

* Swap: Token exchange functionality
* Revoke approvals: Manage token approvals

### ✅ Data Availability

**Target Date:** Q2 2025

* Celestia DA for rollups

### ✅ Enhanced Name Service Support

**Target Date:** Q2 2025

* Extend ENS support to Ethereum L2 explorers
* Enable multiple name services on a single chain

### ✅ Token Information Service

**Target Date:** Q2 2025

* Integrate CEX/DEX data: Information from centralized and decentralized exchanges
* Display liquidity pairs data
* Capture token prices from multiple sources for accuracy

## ✅ Previously Completed

###

### ✅ Basic ENS Support

**Target Date:** Q2 2024

**Status**: ✅ Completed

* ✅ Resolving ENS names for addresses and listing names for the address
* ✅ Enabling search by ENS name
* ✅ Search by ENS name

### ✅ Visualizer Service

**Target Date:** Q2 2024

**Status**: ✅ Completed

Visualizer service offering various visualization schemes, such as Sol2UML and transaction graphs for complex blockchain data analysis.

### ✅ Ongoing L2 support

**Target Date:** Q2 2024

**Status**: ✅ Completed

* zkSync Era and zkSync Sepolia Testnet
* Arbitrum

### ✅ Gas Tracker

**Target Date:** Q2 2024

**Status**: ✅ Completed

Users can monitor gas prices and trends to help them make informed decisions about transaction fees and timing.

### ✅ Human Readable Transactions v1

**Target Date:** Q1 2024

**Status**: ✅ Completed

Display complex transactions in an easily understandable format for non-technical users. This includes the ability to automatically decode transaction data, including tokens, contracts, and events.

### ✅ Universal Smart Contract front-end

**Target Date:** Q3 2023

**Status**: ✅ Completed

Improve and simplify the Smart Contract deployment & verification process. Integrate React components to abstract away common on-chain operations.

### ✅ Improved Indexer Performance

**Target Date:** Q2 2023

**Status**: ✅ Completed

Load speed, database optimization & caching, data parsing features to maintain optimal performance. These efforts will continue as additional features are added to BlockScout.

### ✅ Advanced Filter and Sort

**Target Date:** Q2 2023

**Status**: ✅ Completed

Enhance filter and sort options so users can view transaction data in various formats including transaction types, assets & time ranges. Explore ability to save and share custom filter configurations.

### ✅ My Account Improvements

**Target Date:** Q2 2023

**Status**: ✅ Completed

My Account beta is active and will be rolled out on a case-by-base basis, with hosted instances receiving priority. Includes adding the following features:

* Watchlists: Users can create watchlists for specific addresses or contracts, and view all transactions from the watchlists on the main page.
* Enhanced CSV export features
* Smart contract ownership verification
* Airdrop eligibility tool

### ✅ Admin Dashboard

**Target Date:** Q2 2023

**Status**: ✅ Completed

Rust microservice which will provide a comprehensive dashboard for blockchain administrators. Available for hosted versions first.

* Token info
* Public tags
* Real-time network monitoring, chain statistics, user analytics

### ✅ Landing Page

**Target Date:** Q3 2022

**Status**: ✅ Completed

A new landing page is in development for Blockscout to assist new users and developers understand the Blockscout feature set and find information quickly.

### ✅ UI Redesign

**Target Date:** Q3-Q4 2022

**Status**: ✅ v1 Completed see [https://eth-goerli.blockscout.com/](https://eth-goerli.blockscout.com/)

A new UI interface is under development to improve data exploration, optimize views, and provide overall better UX for Blockscout users. The UI is being built from the ground up. It will overhaul all aspects of Blockscout engagement, creating a complete all-in-one interface for chain exploration. In addition to a modern design, the upgrade will also improvements to features such as:

* **Search**: Prominent search, mobile upgrades, improved dropdown, full-page results, search control
* **Data Sort/Filtering**: Ability to sort data (ascending & descending by column). Improved pagination and filtering abilities.
* **My Account**: See below for features related to My Account functionality.

### ✅ DApp Marketplace v1

**Target Date:** Q4 2022

**Status**: ✅ v1 Completed

Chain users will be able to access applications and modules directly from Blockscout, vastly improving the overall chain experience. Interoperability, swaps, transactions, and 3rd party project-based apps will be accessible and integrated with the modular interface.

Blockscout will also develop native applications for this marketplace. Several are in active development.

* **Blockscout Swap**: Swap feature using an aggregator under the hood for simple swaps without leaving Blockscout.
* **Blockscout Revoke**: Find contracts/apps you have granted allowances to (the ability to spend tokens on your behalf) and revoke these permissions.
* More TBD

### ✅ My Account Functionality v1

**Target Date:** Q3 2022

**Status**: ✅ Instance deployed on Gnosis Chain. Undergoing improvements.

We will explore adding account features for users looking for explorer personalizations, including alerts and notifications, the ability to watch specific addresses, name and customize data within the dashboard, and other advanced features.

### ✅ Blockscout Rust Microservices v1

**Target Date:** Q3 2022

**Status**: ✅ v1 completed - Smart Contract Verification microservice

New Rust-developed microservices will be enabled on Blockscout to extend functionality and modularity. We are revamping smart contract verification to use a Rust module and working on a smart contract uml visualization module to start.

### ✅ Deployment Improvements

**Target Date:** Q3 2022

**Status**: ✅ Completed, Documentation in progress

BlockScout deployment can be complicated for new users. Deployment improvements within a Docker environment will enable a fast path for easy setup and deployment.

### ✅ Ethereum Mainnet BlockScout Instance

**Target Date:** Q2 2022

**Status**: ✅ Instance deployed, optimizations ongoing.

BlockScout offered prior support for the Ethereum mainnet. This instance was discontinued; however a new instance is now planned to further increase explorer diversity on Ethereum and provide additional transparency for Ethereum users.

### ✅ ERC721 Metadata

**Target Date:** Q4 2019

**Status:** ✅ Complete, ERC721 Metadata storage and display ([Release 2.1.0](https://forum.poa.network/t/blockscout-2-1-0-release/3128)) and verification checks ([Release 2.1.1](https://forum.poa.network/t/blockscout-2-1-1-release/3172)) are implemented.

[ERC-721](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md) non-fungible tokens represent ownership of digital or physical assets. Each token is unique, and may include images and other data which identifies the asset and provides additional information. This might include registration information (for example land, property or art registration), identifying numbers or other data unique to that token. As ERC-721 tokens continue to proliferate, it is important to display the relevant information related to each owned token.

### ✅ Staking DApp Integration

**Target Date:** Q3 2020

**Status:** ✅ Complete Q4 2020

BlockScout will support the new POSDAO staking consensus mechanism through an on-board UI. The initial implementation will support the [xDai Stable Chain](https://xdaichain.com). This will allow users to place stake directly from the interface, monitor validator activity, and participate in consensus on the xDai Chain.

### ✅ Smart Contract Write Functionality

**Target Date:** Q2 - Q3 2020

**Status**: ✅ Complete, Write contract/ write proxy functionalities are implemented ([Release 3.3.0](https://forum.poa.network/t/blockscout-v3-3-0-beta/3558)).

Users can currently verify and read contracts on BlockScout. The next smart contract development phase will allow users to interact with contracts directly through the interface. Verified contract methods will be accessible and users can connect through a web3 wallet (such as MetaMask) to access and execute contract functions.

### ✅ ERC1155 Support

**Target Date:** Q2 2021

**Status**: ✅ Basic Functionality added for xDai chain, additional support in process.

ERC-1155 tokens are increasing in popularity as a way to manage multiple-token types including fungible and non-fungible tokens within a single instance. This feature provides parsing and display of tokens contained within an ERC-1155. Additional functionality such as metadata display is in process.

### ✅ Rollup Support

**Target Date:** Q4 2021

**Status**: ✅ Instances for Optimism and Arbitrum on Gnosis Chain

BlockScout availability and support is available for Optimism and Arbitrum on the Gnosis Chain. Includes tracking for gas price on L1 and the L2 implementations. Currently Optimism is the favored deployment.

* Optimism: [https://blockscout.com/xdai/optimism](https://blockscout.com/xdai/optimism)
* Arbitrum: [https://blockscout.com/xdai/aox/](https://blockscout.com/xdai/aox/)

### ✅ EIP-1559 Support

**Target Date:** Q3-Q4 2021

**Status**: ✅ Complete

The Gnosis Chain explorer supports EIP-1559 functionality with a stated transaction type (2 for EIP-1559) and includes data reporting of Max Fee per Gas, Max Priority Fee per Gas and Priority Fee / Tip paid for a transaction.

### ✅ Multi-file Contract Source Code Verification

**Target Date:** Q4 2021

**Status:** ✅ Complete

BlockScout supports verification for contracts via multiple methods including Hardhat and the Hardhat and Sourcify plugins. [More information is available here](/devs/verification).

## Change Log

<table>
  <thead>
    <tr>
      <th>Update</th>
      <th>Items</th>
    </tr>
  </thead>

  <tbody>
    <tr>
      <td>30.09.2025</td>

      <td>
        Updated 2025 with remaining items and moved items from Q1/Q2 to completed or Q3-4 2025 based on status.

        <br />

        <br />

        Moved to Q3/Q4

        <ul>
          <li>Analytics and Statistics</li>
          <li>NFT explorer enhancements</li>
        </ul>

        Completed Items

        <ul>
          <li>Account Abstraction</li>
          <li>Advanced Features</li>
          <li>Analytics and Statistics</li>
          <li>DeFi Integrations</li>
          <li>Data Availability (Celestia Support)</li>
          <li>Enhanced ENS Support</li>
          <li>Token Info Services</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>19.08.2024</td>

      <td>
        Major update to restructure roadmap for the rest of 2024. Moved completed items from Q1-2 into completed section and adjusted remaining items to fit into targeted areas for the remainder of 2024.\
        \
        Removed from Roadmap:

        <ul>
          <li>New Microservices (folded into existing categories)</li>

          <li>CEX/DEX views (deprioritized)</li>

          <li>Ongoing Improvements (moved to existing categories)</li>
        </ul>

        Moved to Completed:

        <ul>
          <li>L2 Support</li>

          <li>Visualizer Service</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>29.05.2024</td>

      <td>
        Minor update: Will be adding a major overhaul in June for Q3-Q4 and will reconfigure, add new items and remove others.\
        \
        **Completed:**

        <ul>
          <li>Gas Tracker</li>

          <li>Basic ENS support</li>
        </ul>

        **Removed:**

        <ul>
          <li>AWS template</li>

          <li>Multisender native dapp</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>03.01.2024</td>

      <td>
        Update milestones for Q1 2024.\
        Completed:

        <ul>
          <li>Universal smart contract front-end</li>
          <li>Human readable transactions v1</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>07.11.2023</td>

      <td>
        Updated milestones to reflect current quarterly work. A more extensive update with many reworked milestones will be added for 2024.
      </td>
    </tr>

    <tr>
      <td>10.08.2023</td>

      <td>
        Updated Q3 milestones to account for completed items.\
        Completed:

        <ul>
          <li>Improved indexer performance</li>

          <li>Advanced filter and search</li>

          <li>My Account improvements</li>

          <li>Admin Account</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>17.04.2023</td>

      <td>
        <ul>
          <li>Revamp roadmap for 2023 milestones by Q.</li>

          <li>Moved all In-research items to appropriate Q.</li>

          <li>
            Added:

            <ul>
              <li>Q2,Q3,Q4 2023 items</li>
            </ul>
          </li>

          <li>
            Completed:

            <ul>
              <li>Landing Page</li>

              <li>React UI v1</li>

              <li>Rust Microservices v1</li>

              <li>DApp Marketplace v1</li>

              <li>My Account v1</li>
            </ul>
          </li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>27.07.2022</td>

      <td>
        <ul>
          <li>Updated marketplace to include Blockscout native DApps</li>

          <li>Added Blockscout Microservices</li>

          <li>Added Multi-chain search</li>

          <li>Added personal asset management features</li>

          <li>Added Blockscout ID</li>

          <li>Combined several elements into UI category</li>

          <li>Deployment improvements (Docker image) moved to completed</li>

          <li>Update Research Phase items to 2023</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>06.07.2022</td>

      <td>
        Added:

        <ul>
          <li>Analytics Dashboards</li>

          <li>UI Overhaul</li>

          <li>Modular Plug-and-Play Library</li>
        </ul>

        Completed:

        <ul>
          <li>Ethereum Mainnet Instance</li>
        </ul>
      </td>
    </tr>

    <tr>
      <td>11.04.2022</td>

      <td>
        <ul>
          <li>Rearranged into Completed and Ongoing Categories</li>

          <li>Updated Ongoing Item dates</li>

          <li>Added UI enhancements</li>
        </ul>

        Marked as Completed

        <ul>
          <li>EIP-1559 Support</li>

          <li>Rollup Support</li>

          <li>Multi-file Contract Source Code Verification</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>


# Get apiv1celestiablob
Source: https://docs.blockscout.com/api-reference/celestiaservice/get-apiv1celestiablob

openapi.yaml get /api/v1/celestia/blob



# Get apiv1celestial2batchmetadata
Source: https://docs.blockscout.com/api-reference/celestiaservice/get-apiv1celestial2batchmetadata

openapi.yaml get /api/v1/celestia/l2BatchMetadata



# If the requested service is unknown, the call will fail with status
NOT_FOUND.
Source: https://docs.blockscout.com/api-reference/celestiaservice/if-the-requested-service-is-unknown-the-call-will-fail-with-statusnot_found

openapi.yaml get /health



# get account abstraction indexing status
Source: https://docs.blockscout.com/api-reference/get-account-abstraction-indexing-status

openapi.yaml get /proxy/account-abstraction/status



# get address coin balance history
Source: https://docs.blockscout.com/api-reference/get-address-coin-balance-history

openapi.yaml get /addresses/{address_hash}/coin-balance-history



# get address coin balance history by day
Source: https://docs.blockscout.com/api-reference/get-address-coin-balance-history-by-day

openapi.yaml get /addresses/{address_hash}/coin-balance-history-by-day



# get address counters
Source: https://docs.blockscout.com/api-reference/get-address-counters

openapi.yaml get /addresses/{address_hash}/counters



# get address info
Source: https://docs.blockscout.com/api-reference/get-address-info

openapi.yaml get /addresses/{address_hash}



# get address internal transactions
Source: https://docs.blockscout.com/api-reference/get-address-internal-transactions

openapi.yaml get /addresses/{address_hash}/internal-transactions



# get address logs
Source: https://docs.blockscout.com/api-reference/get-address-logs

openapi.yaml get /addresses/{address_hash}/logs



# get address token transfers
Source: https://docs.blockscout.com/api-reference/get-address-token-transfers

openapi.yaml get /addresses/{address_hash}/token-transfers



# get address transactions
Source: https://docs.blockscout.com/api-reference/get-address-transactions

openapi.yaml get /addresses/{address_hash}/transactions



# get address withdrawals
Source: https://docs.blockscout.com/api-reference/get-address-withdrawals

openapi.yaml get /addresses/{address_hash}/withdrawals



# get all tokens balances for the address
Source: https://docs.blockscout.com/api-reference/get-all-tokens-balances-for-the-address

openapi.yaml get /addresses/{address_hash}/token-balances



# get block info
Source: https://docs.blockscout.com/api-reference/get-block-info

openapi.yaml get /blocks/{block_number_or_hash}



# get block transactions
Source: https://docs.blockscout.com/api-reference/get-block-transactions

openapi.yaml get /blocks/{block_number_or_hash}/transactions



# get block withdrawals
Source: https://docs.blockscout.com/api-reference/get-block-withdrawals

openapi.yaml get /blocks/{block_number_or_hash}/withdrawals



# get blocks
Source: https://docs.blockscout.com/api-reference/get-blocks

openapi.yaml get /blocks



# get blocks validated by address
Source: https://docs.blockscout.com/api-reference/get-blocks-validated-by-address

openapi.yaml get /addresses/{address_hash}/blocks-validated



# get human-readable transaction summary
Source: https://docs.blockscout.com/api-reference/get-human-readable-transaction-summary

openapi.yaml get /transactions/{transaction_hash}/summary



# get indexing status
Source: https://docs.blockscout.com/api-reference/get-indexing-status

openapi.yaml get /main-page/indexing-status



# get internal transactions
Source: https://docs.blockscout.com/api-reference/get-internal-transactions

openapi.yaml get /internal-transactions



# get json rpc url
Source: https://docs.blockscout.com/api-reference/get-json-rpc-url

openapi.yaml get /config/json-rpc-url



# get list of NFT owned by address
Source: https://docs.blockscout.com/api-reference/get-list-of-nft-owned-by-address

openapi.yaml get /addresses/{address_hash}/nft



# get list of NFT owned by address, grouped by collection
Source: https://docs.blockscout.com/api-reference/get-list-of-nft-owned-by-address-grouped-by-collection

openapi.yaml get /addresses/{address_hash}/nft/collections



# get main page blocks
Source: https://docs.blockscout.com/api-reference/get-main-page-blocks

openapi.yaml get /main-page/blocks



# get main page transactions
Source: https://docs.blockscout.com/api-reference/get-main-page-transactions

openapi.yaml get /main-page/transactions



# get market chart
Source: https://docs.blockscout.com/api-reference/get-market-chart

openapi.yaml get /stats/charts/market



# get native coin holders list
Source: https://docs.blockscout.com/api-reference/get-native-coin-holders-list

openapi.yaml get /addresses



# get NFT instance by id
Source: https://docs.blockscout.com/api-reference/get-nft-instance-by-id

openapi.yaml get /tokens/{address_hash}/instances/{id}



# get NFT instances
Source: https://docs.blockscout.com/api-reference/get-nft-instances

openapi.yaml get /tokens/{address_hash}/instances



# get smart contract
Source: https://docs.blockscout.com/api-reference/get-smart-contract

openapi.yaml get /smart-contracts/{address_hash}



# get stats counters
Source: https://docs.blockscout.com/api-reference/get-stats-counters

openapi.yaml get /stats



# get token holders
Source: https://docs.blockscout.com/api-reference/get-token-holders

openapi.yaml get /tokens/{address_hash}/holders



# get token holders
Source: https://docs.blockscout.com/api-reference/get-token-holders-1

openapi.yaml get /tokens/{address_hash}/counters



# get token info
Source: https://docs.blockscout.com/api-reference/get-token-info

openapi.yaml get /tokens/{address_hash}



# get token instance holders
Source: https://docs.blockscout.com/api-reference/get-token-instance-holders

openapi.yaml get /tokens/{address_hash}/instances/{id}/holders



# get token token transfers
Source: https://docs.blockscout.com/api-reference/get-token-token-transfers

openapi.yaml get /tokens/{address_hash}/transfers



# get token transfers
Source: https://docs.blockscout.com/api-reference/get-token-transfers

openapi.yaml get /token-transfers



# get tokens list
Source: https://docs.blockscout.com/api-reference/get-tokens-list

openapi.yaml get /tokens



# get transaction info
Source: https://docs.blockscout.com/api-reference/get-transaction-info

openapi.yaml get /transactions/{transaction_hash}



# get transaction internal transactions
Source: https://docs.blockscout.com/api-reference/get-transaction-internal-transactions

openapi.yaml get /transactions/{transaction_hash}/internal-transactions



# get transaction logs
Source: https://docs.blockscout.com/api-reference/get-transaction-logs

openapi.yaml get /transactions/{transaction_hash}/logs



# get transaction raw trace
Source: https://docs.blockscout.com/api-reference/get-transaction-raw-trace

openapi.yaml get /transactions/{transaction_hash}/raw-trace



# get transaction state changes
Source: https://docs.blockscout.com/api-reference/get-transaction-state-changes

openapi.yaml get /transactions/{transaction_hash}/state-changes



# get transaction token transfers
Source: https://docs.blockscout.com/api-reference/get-transaction-token-transfers

openapi.yaml get /transactions/{transaction_hash}/token-transfers



# get transactions
Source: https://docs.blockscout.com/api-reference/get-transactions

openapi.yaml get /transactions



# get transactions chart
Source: https://docs.blockscout.com/api-reference/get-transactions-chart

openapi.yaml get /stats/charts/transactions



# get transfers count of NFT instance
Source: https://docs.blockscout.com/api-reference/get-transfers-count-of-nft-instance

openapi.yaml get /tokens/{address_hash}/instances/{id}/transfers-count



# get transfers of NFT instance
Source: https://docs.blockscout.com/api-reference/get-transfers-of-nft-instance

openapi.yaml get /tokens/{address_hash}/instances/{id}/transfers



# get verified smart contracts
Source: https://docs.blockscout.com/api-reference/get-verified-smart-contracts

openapi.yaml get /smart-contracts



# get verified smart contracts counters
Source: https://docs.blockscout.com/api-reference/get-verified-smart-contracts-counters

openapi.yaml get /smart-contracts/counters



# get withdrawals
Source: https://docs.blockscout.com/api-reference/get-withdrawals

openapi.yaml get /withdrawals



# Delete adminapiv1offers secrets
Source: https://docs.blockscout.com/api-reference/pointsadminservice/delete-adminapiv1offers-secrets

merits-admin-service.yaml delete /admin/api/v1/offers/{offer_id}/secrets/{secret_id}



# Get adminapiv1codes
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1codes

merits-admin-service.yaml get /admin/api/v1/codes



# Get adminapiv1distributions
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1distributions

merits-admin-service.yaml get /admin/api/v1/distributions/{distribution_id}



# Get adminapiv1networks
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1networks

merits-admin-service.yaml get /admin/api/v1/networks



# Get adminapiv1networks 1
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1networks-1

merits-admin-service.yaml get /admin/api/v1/networks/{chain_id}



# Get adminapiv1offers redemptions
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1offers-redemptions

merits-admin-service.yaml get /admin/api/v1/offers/{offer_id}/redemptions



# Get adminapiv1offers secrets
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1offers-secrets

merits-admin-service.yaml get /admin/api/v1/offers/{offer_id}/secrets



# Get adminapiv1users
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1users

merits-admin-service.yaml get /admin/api/v1/users



# Get adminapiv1users 1
Source: https://docs.blockscout.com/api-reference/pointsadminservice/get-adminapiv1users-1

merits-admin-service.yaml get /admin/api/v1/users/{address_or_code}



# Patch adminapiv1codes
Source: https://docs.blockscout.com/api-reference/pointsadminservice/patch-adminapiv1codes

merits-admin-service.yaml patch /admin/api/v1/codes



# Patch adminapiv1networks
Source: https://docs.blockscout.com/api-reference/pointsadminservice/patch-adminapiv1networks

merits-admin-service.yaml patch /admin/api/v1/networks/{chain_id}



# Patch adminapiv1offers
Source: https://docs.blockscout.com/api-reference/pointsadminservice/patch-adminapiv1offers

merits-admin-service.yaml patch /admin/api/v1/offers/{offer_id}



# Post adminapiv1codes
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1codes

merits-admin-service.yaml post /admin/api/v1/codes



# Post adminapiv1distribute
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1distribute

merits-admin-service.yaml post /admin/api/v1/distribute



# Post adminapiv1networks
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1networks

merits-admin-service.yaml post /admin/api/v1/networks/{chain_id}



# Post adminapiv1offers
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1offers

merits-admin-service.yaml post /admin/api/v1/offers/{offer_id}



# Post adminapiv1offers secrets
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1offers-secrets

merits-admin-service.yaml post /admin/api/v1/offers/{offer_id}/secrets



# Post adminapiv1users code
Source: https://docs.blockscout.com/api-reference/pointsadminservice/post-adminapiv1users-code

merits-admin-service.yaml post /admin/api/v1/users/{address}/code



# re-fetch token instance metadata
Source: https://docs.blockscout.com/api-reference/re-fetch-token-instance-metadata

openapi.yaml patch /tokens/{address_hash}/instances/{id}/refetch-metadata



# search
Source: https://docs.blockscout.com/api-reference/search

openapi.yaml get /search



# search redirect
Source: https://docs.blockscout.com/api-reference/search-redirect

openapi.yaml get /search/check-redirect



# token balances with filtering and pagination
Source: https://docs.blockscout.com/api-reference/token-balances-with-filtering-and-pagination

openapi.yaml get /addresses/{address_hash}/tokens



# Blockscout APIs
Source: https://docs.blockscout.com/devs/apis

How to use Blockscout APIs

## Blockscout API Usage

API information can be accessed from the Blockscout main menu, footer or header depending on the instance.

Blockscout supports several methods:

1. [**REST API**](/devs/apis/rest): API that serves the UI for Blockscout.
2. [**RPC API**](/devs/apis/rpc): provided for developers transitioning applications from Etherscan to Blockscout. Supports GET and POST requests, simply replace Etherscan url with Blockscout url to use the RPC.
3. [**Eth RPC API**](/devs/apis/rpc/eth-rpc): Supports the most popular [JSON RPC methods](https://ethereum.github.io/execution-apis/api-documentation/).
4. [**Graphiql**](https://github.com/graphql/graphiql): An IDE for exploring GraphQL.

## API Keys

* More info on [My Account and adding API Keys](/using-blockscout/my-account/api-keys)
* More info on [API Requests and Limits](/devs/apis/requests-and-limits)

<Info>
  Blockscout provides swagger documentation for various API services here: [https://blockscout.github.io/swaggers/](https://blockscout.github.io/swaggers/)
</Info>

<Frame>
  <img alt="" />
</Frame>

## Blockscout Internal Documentation

To view Modules and API Reference documentation:

1. Generate documentation.

   `mix docs`
2. View the generated docs.

   `open doc/index.html`


# Blockscout APIs
Source: https://docs.blockscout.com/devs/apis-redirect





# GraphQL in Blockscout
Source: https://docs.blockscout.com/devs/apis/graphql



## **What is GraphQL**

GraphQL is an open-source data query and manipulation language for APIs, and a runtime for fulfilling queries with existing data. It provides an efficient, powerful and flexible approach to developing web APIs. It allows clients to define the structure of the data required, and exactly the same structure of the data is returned from the server, therefore preventing excessively large amounts of data from being returned.

Key concepts of the GraphQL query language are:

* Hierarchical

* Strongly typed

* Client-specified queries

Advantages of GraphQL:

* Declarative integration on client (what data/operations do I need)

* A standard way to expose data and operations

* Support for real-time data (with subscriptions)

## **Query types**

There are three main query types in GraphQL schema:

1\) **Query:** fetch data

```
query {
  allPosts {
    description
    text
  }
}
```

2\) **Mutation:** change data.

```javascript theme={null}
   mutation {
     updatePost(id: 1, text: "text") {
       text
     }
   }
```

1. **Subscription:** subscribe to real-time data.

```javascript theme={null}
subscription {
  newPost(category: [1]) {
    description
    text
  }
}
```

## **Access GraphQL API**

To access Blockscout GraphQL interface you can use GraphiQL - in-browser IDE for exploring GraphQL. It's built in to Blockscout. From the `APIs` dropdown menu choose `GraphQL.`

<Frame>
  <img />
</Frame>

You can also use your favorite http client:

```sh theme={null}
curl 'https://eth-sepolia.blockscout.com/graphiql'
  -H 'Authorization: Bearer YOUR_AUTH_TOKEN'
  -d '{"query":""{transaction(hash:\"0x4f3a80620613d18a5073108f56558c7cbf0020c8ccb1acbad2c1f1fe3714e5ce\"){blockNumbertoAddressHashfromAddressHashcreatedContractAddressHashvaluestatusnoncehasherrorgasgasPricegasUsedcumulativeGasUsedidindexinputrsv}}""}'
```

## **Queries**

Blockscout's GraphQL API provides queries and a subscription. You can view them in the GraphQL interface in the `Docs` menu. Example Queries:

| Query                                           | Description                 | Example                                                                                                                                    |
| ----------------------------------------------- | --------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
| address(hash: AddressHash!): Address            | Gets an address by hash     | \{address(hash: "0x1fddEc96688e0538A316C64dcFd211c491ECf0d8") \{hash, contractCode} }                                                      |
| addresses (hashes: \[AddressHash!]): \[Address] | Gets addresses by hashes    | \{addresses(hashes: \["0x1fddEc96688e0538A316C64dcFd211c491ECf0d8", "0x3948c17c0f45017064858b8352580267a85a762c"]) \{hash, contractCode} } |
| block(number: Int!): Block                      | Gets a block by number      | \{block(number: 1) \{parentHash, size, nonce}}                                                                                             |
| transaction (hash: FullHash!): Transaction      | Gets a transaction by hash. | \{transaction(hash: "0xc391da8f433b3bea0b3eb45da40fdd194c7a0e07d1b5ad656bf98940f80a6cf6") \{input, gasUsed}}                               |

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

### Example Query to retrieve transactions for a specific address

```javascript theme={null}
{
  address(hash: "0x...") {
    transactions(first:5) {
      edges {
        node {
          blockNumber
          createdContractAddressHash
          fromAddressHash
          gas
          hash
        }
      }
    }
  }
}
```

Note that transactions can accept the following arguments:

* first

* after

* before


# Requests & Limits
Source: https://docs.blockscout.com/devs/apis/requests-and-limits

API variables and info

* Please note this table scrolls horizontally
* Default API rate limit is 5 requests per second without an API key

| **Type of API key**              | **Rate limitvalue, req/sec** | **API key is defined by env variable (if applicable)** | **Rate limit for the API key managed by env variable**                                | **Description**                                                                                                                                                                                                                           |
| -------------------------------- | ---------------------------- | ------------------------------------------------------ | ------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| No API key (by IP)               | 5                            |                                                        | `API_RATE_LIMIT_BY_IP` & `API_RATE_LIMIT_BY_IP_TIME_INTERVAL`                         | The default rate limit is 300 requests per minute. This limit applies to all requests that are not from whitelisted addresses and do not use an API key.                                                                                  |
| Temp token                       | 5                            |                                                        | `API_RATE_LIMIT_UI_V2_WITH_TOKEN` & `API_RATE_LIMIT_UI_V2_WITH_TOKEN_TIME_INTERVAL`   | When frontend user reaches the default IP limit, they must solve a captcha to obtain a temporary token. This token provides a personal (not per-IP) rate limit of 5 req/sec. Token TTL is configured via `API_RATE_LIMIT_UI_V2_TOKEN_TTL` |
| Individual API key               | 10                           |                                                        | `API_RATE_LIMIT_BY_ACCOUNT_API_KEY_TIME_INTERVAL`                                     | An API key can be [created by the user in the My Account section](/using-blockscout/my-account/api-keys)                                                                                                                                  |
| Rate limit, if IP is whitelisted | 25                           | `API_RATE_LIMIT_WHITELISTED_IPS`                       | `API_RATE_LIMIT_BY_WHITELISTED_IP` & `API_RATE_LIMIT_BY_WHITELISTED_IP_TIME_INTERVAL` | Rate limit for requests from whitelisted IPs                                                                                                                                                                                              |
| Per explorer instance API key    | 10                           | `API_RATE_LIMIT_STATIC_API_KEY`                        | `API_RATE_LIMIT_BY_KEY` & `API_RATE_LIMIT_BY_KEY_TIME_INTERVAL`                       | A per-instance API key (*this feature was created before individual API keys existed and may have limited utility*)                                                                                                                       |
| No rate limit API key            | ♾️                           | `API_NO_RATE_LIMIT_API_KEY`                            |                                                                                       | Administrator API key                                                                                                                                                                                                                     |

<Check>
  The default rate limit config of each API endpoint is described [in the codebase](https://github.com/blockscout/blockscout/blob/master/apps/block_scout_web/priv/rate_limit_config.json) and can be re-defined via `API_RATE_LIMIT_CONFIG_URL` env variable. [Here](https://github.com/blockscout/blockscout/blob/master/apps/block_scout_web/rate_limits.md) you can find details on the rate limits config.
</Check>

Some of the API endpoints have their own rate limit before showing captcha to the user:

| **API endpoint**                                         | **Number of requests per period** | **Period** |
| -------------------------------------------------------- | --------------------------------- | ---------- |
| `api/v2/key`                                             | ♾️                                |            |
| `api/v2/import/token-info`                               | ♾️                                |            |
| `api/v2/import/smart-contracts/:param`                   | ♾️                                |            |
| `api/account/v2/authenticate_via_wallet`                 | 1                                 | 1 hour     |
| `api/account/v2/send_otp`                                | 1                                 | 1 hour     |
| `api/v2/tokens/:param/instances/:param/refetch-metadata` | 50                                | 1 hour     |
| `api/v2/advanced-filters/csv`                            | 50                                | 1 hour     |
| `api/v2/tokens/:param/holders/csv`                       | 50                                | 1 hour     |
| `api/v2/addresses/:param/transactions/csv`               | 50                                | 1 hour     |
| `api/v2/addresses/:param/token-transfers/csv`            | 50                                | 1 hour     |
| `api/v2/addresses/:param/internal-transactions/csv`      | 50                                | 1 hour     |
| `api/v2/addresses/:param/logs/csv`                       | 50                                | 1 hour     |
| `api/v2/addresses/:param/election-rewards/csv`           | 50                                | 1 hour     |
| `api/v2/smart-contracts/:param/audit-reports`            | 50                                | 1 hour     |
| `api/health/*`                                           | 5                                 | 1 second   |


# REST API Endpoints
Source: https://docs.blockscout.com/devs/apis/rest



REST API methods are used to render the UI for new versions of Blockscout. These can be accessed and used to get many types of information. Methods parameters and schemas are available at *https\://instance-name/api-docs* (ie [https://eth.blockscout.com/api-docs](https://eth.blockscout.com/api-docs))

<Info>
  Additional information:

  * [Stats queries](/devs/apis/rest/stats-api): Access pre-calculated statistics for a chain

  * [Interpreter queries](/devs/apis/rest/interpreter-api): Transactions populated with contract names, methods, etc for easy interpretation

  <Frame>
    <img alt="" />
  </Frame>
</Info>

<Frame>
  <img />
</Frame>

## Pagination

Blockscout uses the keyset pagination method to quickly return results. By default an API response returns the first 50 results. To access additional results (in groups of 50), add the `next_page_params` to your query.

For example, open [https://eth.blockscout.com/api/v2/transactions](https://eth.blockscout.com/api/v2/transactions) and scroll to the bottom of the response.

<Frame>
  <img />
</Frame>

You will see the `next_page_params` object. Add the parameters from this object to your next query to receive the next 50 results.

[https://eth.blockscout.com/api/v2/transactions?block\_number=18678766\&index=119\&items\_count=50](https://eth.blockscout.com/api/v2/transactions?block_number=18678766\&index=119\&items_count=50)

Repeat this process to continue receiving results in groups of 50 (remove params and substitute the new `next_page_params` found in the body of the query).

<Frame>
  <img />
</Frame>

In this example, the query to receive the next 50 results would be:

[https://eth.blockscout.com/api/v2/transactions?block\_number=18678766\&index=69\&items\_count=100](https://eth.blockscout.com/api/v2/transactions?block_number=18678766\&index=69\&items_count=100)


# Interpreter API
Source: https://docs.blockscout.com/devs/apis/rest/interpreter-api



### [https://eth.blockscout.com/api/v2/transactions/transaction\_hash/summary](https://eth.blockscout.com/api/v2/transactions/transaction_hash/summary)

<Info>
  The Interpreter API is currently in development. This REST API service will provide human-readable information regarding transactions, addresses and more.
</Info>

## How It Works

The Transactions Interpreter Service is designed to process blockchain transactions by extracting and analyzing relevant information to generate a summary of the transaction. The process follows several distinct phases:

1. **Transaction Hash Reception** : The service receives a transaction hash, which triggers the processing pipeline.

2. **Data Retrieval** : The service automatically retrieves necessary transaction data from the blockchain using the provided transaction hash.

3. **Initial Validation** : The input data undergoes validation to ensure authenticity and correctness before further processing.

4. **Data Processing** : The retrieved transaction data is processed, involving multiple phases:

   1. **Pre-LLM Phase** : During this phase, the service attempts to classify and interpret the on-chain actions using predefined algorithms. This step includes determining the type of action (e.g., transfer, minting, etc.) based on the transaction data.

   2. **LLM Phase** : If the type of action cannot be determined algorithmically in the Pre-LLM phase, the service leverages a Language Learning Model (LLM) to infer the type of on-chain action.

5. **Transaction Summary Generation** : After the classification, the service generates a summary of the transaction, which is returned as the response. The summary includes key details about the transaction and is structured according to a specific template.

## Response Structure

The response from the Transactions Interpreter Service is structured as follows (will vary depending on the specific case):

### **Success Response**

```json theme={null}
{
    "success": true,
    "data": {
        "summaries": [
            {
                "summary_template": "{action_type} {amount} {token} to {to_address}",
                "summary_template_variables": {
                    "action_type": {
                        "type": "string",
                        "value": "Transfer"
                    },
                    "amount": {
                        "type": "currency",
                        "value": "7800"
                    },
                    "token": {
                        "type": "token",
                        "value": {
                            "address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
                            "circulating_market_cap": "34593435047.40006",
                            "decimals": "6",
                            "exchange_rate": "1.001",
                            "holders": "2761518",
                            "icon_url": "<https://assets.coingecko.com/coins/images/6319/small/usdc.png?1696506694>",
                            "name": "USD Coin",
                            "symbol": "USDC",
                            "total_supply": "25611927821576420",
                            "type": "ERC-20",
                            "volume_24h": "8858197053.476923"
                        }
                    },
                    "to_address": {
                        "type": "address",
                        "value": {
                            "hash": "0x242ba6d68FfEb4a098B591B32d370F973FF882B7"
                        }
                    }
                }
            }
        ],
        "debug_data": {
            "transaction_hash": "0xea7cbead745789346343435cf2a0910887ab0ebef08af07cbd2f0920a2c628da",
            "model_classification_type": "transfer",
            "post_llm_classification_type": "transfer",
            "is_prompt_truncated": false,
            "summary_template": {
                "transfer": {
                    "template_name": "Generic-Transfer",
                    "template_vars": {
                        "strippedInput": "<stripped data>",
                        "decodedInput": "<decoded data>",
                        "tokenTransfers": [<token transfer details>],
                        "isErc20Transfer": true,
                        "erc20Amount": "7800",
                        "isNftTransfer": false,
                        "token": {
                            "address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
                            "circulating_market_cap": "34593435047.40006",
                            "decimals": "6",
                            "exchange_rate": "1.001",
                            "holders": "2761518",
                            "icon_url": "<https://assets.coingecko.com/coins/images/6319/small/usdc.png?1696506694>",
                            "name": "USD Coin",
                            "symbol": "USDC",
                            "total_supply": "25611927821576420",
                            "type": "ERC-20",
                            "volume_24h": "8858197053.476923"
                        },
                        "nftAmount": null,
                        "toAddress": {
                            "hash": "0x242ba6d68FfEb4a098B591B32d370F973FF882B7"
                        }
                    }
                }
            }
        }
    }
}
```

### **Response Variable Types**

The response from the service can contain the following types of data:

* `number`: Numerical values.

* `string`: Textual data.

* `array`: An array of items.

* `currency`: Represents a monetary value.

* `token`: Information related to a cryptocurrency or token.

* `address`: Blockchain address information.

* `timestamp`: A date and time representation.

* `domain`: Domain name data.

* `code`: Code snippets or encoded data.

These types are used to ensure that the data returned in the summary is consistent and properly structured.

## Error Handling

If the service encounters an error, it returns a structured error response:

* **Error Response**:

```json theme={null}
{
  "success": false,
  "error": {
    "id": "v_ap_rd_1",
    "code": "INVALID_API_PARAMS",
    "message": "Invalid API parameters",
    "error_data": [
      {
        "parameter": "data",
        "message": "Invalid parameter data. Please ensure the input is well formed."
      }
    ]
  }
}
```

### **Attributes of the Error Object**

* `id`: A unique identifier for the error, used for debugging purposes.

* `code`: A code representing the type of error.

* `message`: A user-friendly message that can be displayed on the front end.

* `error_data`: An array containing details about the invalid parameters.


# Stats API
Source: https://docs.blockscout.com/devs/apis/rest/stats-api



The [stats microservice](https://github.com/blockscout/blockscout-rs/tree/main/stats) collects data from a Blockscout instance and calculates statistics based on predefined values. The calculated data is available through a REST API, providing access to this statistical information.

*Endpoint info in process*


# JSON RPC & ETH Compatible RPC Endpoints
Source: https://docs.blockscout.com/devs/apis/rpc

API designed for ease of use

This API is provided for developers transitioning applications from Etherscan to BlockScout and applications requiring general API and data support. It supports GET and POST requests.

<Info>
  URLs vary by instance. With typical installations, access the API by adding `/api` to the end of the url. For example with the Sepolia instance.

  * URL: [https://eth-sepolia.blockscout.com](https://eth-sepolia.blockscout.com/)

  * API URL: [https://eth-sepolia.blockscout.com/api](https://eth-sepolia.blockscout.com/api)

  An example query includes a module and action(s)/parameters. For example: [https://eth-sepolia.blockscout.com/api?module=**account**\&action=**listaccounts**\&page=2\&offset=5](https://eth-sepolia.blockscout.com/api?module=account\&action=listaccounts\&page=2\&offset=5)
</Info>

The following modules are supported. Click through to see specific endpoints and parameters.

|                                           |                       |
| ----------------------------------------- | --------------------- |
| [Account](/devs/apis/rpc/account)         | `?module=account`     |
| [Logs](/devs/apis/rpc/logs)               | `?module=logs`        |
| [Token](/devs/apis/rpc/token)             | `?module=token`       |
| [Stats](/devs/apis/rpc/stats)             | `?module=stats`       |
| [Block](/devs/apis/rpc/block)             | `?module=block`       |
| [Contract](/devs/apis/rpc/contract)       | `?module=contract`    |
| [Transaction](/devs/apis/rpc/transaction) | `?module=transaction` |


# Account
Source: https://docs.blockscout.com/devs/apis/rpc/account

?module=account

### `https://instance_base_url/api?module=account`

## Return balance from a provided block

`eth_get_balance`

Mimics Ethereum JSON RPC's eth\_getBalance

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=eth_get_balance
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                                                                                                                                                                                                                                                 |
    | ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
    | **address** | `string` containing the address hash.                                                                                                                                                                                                                       |
    | block       | optional. Block number as a string, or `latest`, `earliest` or `pending` Latest is the latest balance in a *consensus* block. Earliest is the first recorded balance for the address. Pending is the latest balance in a consensus *or* nonconsensus block. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "id": 1,
      "jsonrpc": "2.0",
      "result": "0x0234c8a3397aab58"
    }
    ```
  </Tab>
</Tabs>

## Get the native token balance for an address

`balance`

Many chains use their own native tokens. On Ethereum, this will return the result in "Ether", on Gnosis it will be "xDai", etc. Results are returned in wei.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=balance
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                           |
    | ----------- | ------------------------------------- |
    | **address** | `string` containing the address hash. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "663046792267785498951364",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

<Info>
  Also available through a GraphQL `address` query.
</Info>

<Info>
  If the balance hasn't been updated recently, the node is double-checked to fetch the absolute latest balance. This will not be reflected in the current request, but once it is updated, subsequent requests will show the updated balance. If you want to know if there is a check for another balance, use the `balancemulti` action. That contains a property called `stale` that will let you know to recheck that balance in the near future.
</Info>

## Get balance for multiple addresses

`balancemulti`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=balancemulti
   &address={addressHash1,addressHash2,addressHash3}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                                                                  |
    | ----------- | ---------------------------------------------------------------------------- |
    | **address** | `string` containing the address hash, comma separated. **Max 20 addresses.** |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "account": "0xddbd2b932c763ba5b1b7ae3b362eac3e8d40121a",
          "balance": "40807168566070000000000",
          "stale": true
        },
        {
          "account": "0x63a9975ba31b0b9626b34300f7f627147df1f526",
          "balance": "332567136222827062478",
          "stale": false
        },
        {
          "account": "0x198ef1ec325a96cc354c7266a038be8b5c558f67",
          "balance": "185178830000000000",
          "stale": false
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

<Info>
  Also available through a GraphQL 'addresses' query
</Info>

<Info>
  If the balance hasn't been updated in a long time, the node is double checked to fetch the absolute latest balance. This is not reflected in the current request, but once it is updated, subsequent requests will show the updated balance. The `stale` attribute will be set to `true` if a new balance is being fetched.
</Info>

## Get pending transactions by address

`pendingtxlist`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=pendingtxlist
   &address={addressHash}
   &page=1
   &offset=5
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                                                                                             |
    | ----------- | ------------------------------------------------------------------------------------------------------- |
    | **address** | `string` containing the address hash.                                                                   |
    | page        | optional `integer` representing the page number used for pagination. 'offset' must also be provided.    |
    | offset      | optional `integer` representing number of transactions returned per page. `page` must also be provided. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "contractAddress": "",
          "cumulativeGasUsed": "122207",
          "from": "0x3fb1cd2cd96c6d5c0b5eb3322d807b34482481d4",
          "gas": "122261",
          "gasPrice": "50000000000",
          "gasUsed": "122207",
          "hash": "0x98beb27135aa0a25650557005ad962919d6a278c4b3dde7f4f6a3a1e65aa746c",
          "input": "0xf00d4b5d000000000000000000000000036c8cecce8d8bbf0831d840d7f29c9e3ddefa63000000000000000000000000c5a96db085dda36ffbe390f455315d30d6d3dc52",
          "nonce": "0",
          "to": "0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae",
          "value": "0"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get transactions by address

`txlist`

Maximum of 10,000 transactions. Also available through a GraphQL 'address' query. For faster results, specify a smaller block range to search using the `startblock` and `endblock` parameters

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=txlist
   &address={addressHash}
   &startblock=555555
   &endblock=666666
   &page=1
   &offset=5
   &sort=asc
```

<Tabs>
  <Tab title="Request Params">
    | Parameter        | Description                                                                                                                                                          |
    | ---------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
    | **address**      | `string` containing the address hash.                                                                                                                                |
    | sort             | optional sorting preference, `asc` for ascending and `desc` for descending. Descending is default.                                                                   |
    | startblock       | optional `integer` block number to start transaction search                                                                                                          |
    | endblock         | optional `integer` block number to stop transaction search.                                                                                                          |
    | page             | optional `integer` representing the page number used for pagination. `offset` must also be provided.                                                                 |
    | offset           | optional `integer` representing number of transactions returned per page. `page` must also be provided.                                                              |
    | filter\_by       | optional string representing the field to filter by. Values include `to` and `from`. If none provided returns transactions that match to, from, or contract address. |
    | start\_timestamp | optional starting block unix timestamp.                                                                                                                              |
    | end\_timestamp   | optional ending block unix timestamp.                                                                                                                                |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockHash": "0x373d339e45a701447367d7b9c7cef84aab79c2b2714271b908cda0ab3ad0849b",
          "blockNumber": "65204",
          "confirmations": "5994246",
          "contractAddress": "",
          "cumulativeGasUsed": "122207",
          "from": "0x3fb1cd2cd96c6d5c0b5eb3322d807b34482481d4",
          "gas": "122261",
          "gasPrice": "50000000000",
          "gasUsed": "122207",
          "hash": "0x98beb27135aa0a25650557005ad962919d6a278c4b3dde7f4f6a3a1e65aa746c",
          "input": "0xf00d4b5d000000000000000000000000036c8cecce8d8bbf0831d840d7f29c9e3ddefa63000000000000000000000000c5a96db085dda36ffbe390f455315d30d6d3dc52",
          "isError": "0",
          "methodId": "0xf00d4b5d",
          "nonce": "0",
          "timeStamp": "1439232889",
          "to": "0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae",
          "transactionIndex": "0",
          "txreceipt_status": "1",
          "value": "0"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get internal transactions

`txlistinternal`

Up to a maximum of 10,000 internal transactions. Also available through a GraphQL 'transaction' query. For faster results, specify a smaller block range to search using the start\_block and end\_block parameters.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=txlistinternal
   &startblock=555555
   &endblock=666666
   &page=1
   &offset=5
   &sort=asc
   &include_zero_value=true
```

<Tabs>
  <Tab title="Request Params">
    | Parameter            | Description                                                                                                                                          |
    | -------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- |
    | **txhash**           | optional `string` representing the transaction hash to check for internal transactions                                                               |
    | address              | optional `string` containing the address hash.                                                                                                       |
    | sort                 | optional sorting preference, `asc` for ascending and `desc` for descending. Descending is default. **Only available if 'address' is provided.**      |
    | startblock           | optional `integer` block number to start transaction search. **Only available if 'address' is provided.**                                            |
    | endblock             | optional `integer` block number to stop transaction search. **Only available if 'address' is provided.**                                             |
    | page                 | optional `integer` representing the page number used for pagination. `offset` must also be provided. **Only available if 'address' is provided.**    |
    | offset               | optional `integer` representing number of transactions returned per page. `page` must also be provided. **Only available if 'address' is provided.** |
    | include\_zero\_value | optional `boolean` representing whether to include zero-value transactions.                                                                          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockNumber": "6153702",
          "callType": "delegatecall",
          "contractAddress": "0x883103875d905c11f9ac7dacbfc16deb39655361",
          "errCode": "",
          "from": "0x2ca1e3f250f56f1761b9a52bc42db53986085eff",
          "gas": "814937",
          "gasUsed": "536262",
          "index": "0",
          "input": "",
          "isError": "0",
          "timeStamp": "1534362606",
          "to": "",
          "transactionHash": "0xd65b788c610949704a5f9aac2228c7c777434dfe11c863a12306f57fcbd8cdbb",
          "type": "call",
          "value": "5488334153118633"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get ERC-20 token transfer events by address

`tokentx`

Up to a maximum of 10,000 ERC-20 token transfer events. Also available through the GraphQL `token_transfers` query.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=tokentx
   &address={addressHash}
   &page=1
   &offset=10
   &sort=asc
```

<Tabs>
  <Tab title="Request Params">
    | Parameter        | Description                                                                                                      |
    | ---------------- | ---------------------------------------------------------------------------------------------------------------- |
    | **address**      | required if no `contractaddress` parameter is provided, `string` containing the address hash.                    |
    | contract address | required if no `address` parameter is provided, `string` with the token contract address to identify a contract. |
    | sort             | optional sorting preference, `asc` for ascending and `desc` for descending. Descending is default.               |
    | startblock       | optional `integer` block number to start transaction search                                                      |
    | endblock         | optional `integer` block number to stop transaction search.                                                      |
    | page             | optional `integer` representing the page number used for pagination. `offset` must also be provided.             |
    | offset           | optional `integer` representing number of transactions returned per page. `page` must also be provided.          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockHash": "0x6169c5dc05d0051564ba3eae8ebfbdefda640c5f5ffc095846b8aed0b44f64ea",
          "blockNumber": "5997843",
          "confirmations": "199384",
          "contractAddress": "0x9f8f72aa9304c8b593d555f12ef6589cc3a579a2",
          "cumulativeGasUsed": "1043649",
          "from": "0x4e83362442b8d1bec281594cea3050c8eb01311c",
          "gas": "44758",
          "gasPrice": "7000000000",
          "gasUsed": "37298",
          "hash": "0xd65b788c610949704a5f9aac2228c7c777434dfe11c863a12306f57fcbd8cdbb",
          "input": "0xa9059cbb00000000000000000000000021e21ba085289f81a86921de890eed30f1ad23750000000000000000000000000000000000000000000000008ac7230489e80000",
          "methodId": "0xa9059cbb",
          "nonce": "765",
          "timeStamp": "1532086946",
          "to": "0x21e21ba085289f81a86921de890eed30f1ad2375",
          "tokenDecimal": "18",
          "tokenName": "Maker",
          "tokenSymbol": "MKR",
          "transactionIndex": "27",
          "value": "10000000000000000000"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

**Usage:**

* To fetch ERC-20 token transfers by address, specify `address` parameter
* To fetch ERC-20 token transfers by token, specify `contractaddress` parameter
* To fetch ERC-20 token transfers by address filtered by token, specify both `address` and `contractaddress` parameters

## Get ERC-721 token transfer events by address

`tokennfttx`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=tokennfttx
   &address={addressHash}
   &page=1
   &offset=10
   &sort=asc
```

<Tabs>
  <Tab title="Request Params">
    | Parameter       | Description                                                                                                      |
    | --------------- | ---------------------------------------------------------------------------------------------------------------- |
    | **address**     | required if no `contractaddress` parameter is provided, `string` containing the address hash.                    |
    | contractaddress | required if no `address` parameter is provided, `string` with the token contract address to identify a contract. |
    | sort            | optional sorting preference, `asc` for ascending and `desc` for descending. Descending is default.               |
    | startblock      | optional `integer` block number to start transaction search                                                      |
    | endblock        | optional `integer` block number to stop transaction search.                                                      |
    | page            | optional `integer` representing the page number used for pagination. `offset` must also be provided.             |
    | offset          | optional `integer` representing number of transactions returned per page. `page` must also be provided.          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockHash": "0xd033832ffd0480a3e3b16362320d4ea247e6905117eaa8741a845ac51bd51b1f",
          "blockNumber": "22895463",
          "confirmations": "13",
          "contractAddress": "0xb6bcaa0c71c90b26f4190418d77ad0b95f656f2c",
          "cumulativeGasUsed": "23511347",
          "from": "0xc8fb7aca6b31dc905647d31ac0383f5b30d9be31",
          "functionName": "transferFrom(address from, address to, uint256 id)",
          "gas": "108139",
          "gasPrice": "5596263013",
          "gasUsed": "71227",
          "hash": "0x76be4925c1a5f268c12a3ae7b60486293a96ebd28dc289064ca687708de46397",
          "input": "0x23b872dd000000000000000000000000c8fb7aca6b31dc905647d31ac0383f5b30d9be31000000000000000000000000d2a999bc8e4ea85131c1800e2a5c606d127533330000000000000000000000000000000000000000000000000000000000000445",
          "methodId": "0x23b872dd",
          "nonce": "376",
          "timeStamp": "1752231191",
          "to": "0xd2a999bc8e4ea85131c1800e2a5c606d12753333",
          "tokenDecimal": "0",
          "tokenID": "1093",
          "tokenName": "SpaceRush Bounty Hunters",
          "tokenSymbol": "SRB",
          "transactionIndex": "360"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

**Usage:**

* To fetch ERC-721 token transfers by address, specify `address` parameter
* To fetch ERC-721 token transfers by token, specify `contractaddress` parameter
* To fetch ERC-721 token transfers by address filtered by token, specify both `address` and `contractaddress` parameters

## Get ERC-1155 token transfer events by address

`token1155tx`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=token1155tx
   &address={addressHash}
   &page=1
   &offset=10
   &sort=asc
```

<Tabs>
  <Tab title="Request Params">
    | Parameter       | Description                                                                                                      |
    | --------------- | ---------------------------------------------------------------------------------------------------------------- |
    | address         | required if no `contractaddress` parameter is provided, `string` containing the address hash.                    |
    | contractaddress | required if no `address` parameter is provided, `string` with the token contract address to identify a contract. |
    | sort            | optional sorting preference, `asc` for ascending and `desc` for descending. Descending is default.               |
    | startblock      | optional `integer` block number to start transaction search                                                      |
    | endblock        | optional `integer` block number to stop transaction search.                                                      |
    | page            | optional `integer` representing the page number used for pagination. `offset` must also be provided.             |
    | offset          | optional `integer` representing number of transactions returned per page. `page` must also be provided.          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockNumber": "22767293",
          "timeStamp": "1750683671",
          "hash": "0xe63f23bc2882dc083cf77c3a9a32efe62a2f045334232c92ed63716368eb56c9",
          "nonce": "332",
          "blockHash": "0x5960ef1fb1a3f424a90723238cf5d91a996cb7344f9ff613f00942ea4f7bcf31",
          "transactionIndex": "52",
          "gas": "198549",
          "gasPrice": "3662960410",
          "gasUsed": "150369",
          "cumulativeGasUsed": "8276535",
          "input": "deprecated",
          "methodId": "0xa64dfa75",
          "functionName": "multiConfigure(address token,tuple config)",
          "contractAddress": "0x81d5cedef14934957232e6673e1b37375e6ec5cd",
          "from": "0x0000000000000000000000000000000000000000",
          "to": "0xa6718ebedb87b85acfb39d8a02759f1be7cb01ed",
          "tokenID": "43",
          "tokenValue": "1",
          "tokenName": "Colored rombs",
          "tokenSymbol": "CR",
          "confirmations": "128226"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

**Usage:**

* To fetch ERC-1155 token transfers by address, specify `address` parameter
* To fetch ERC-1155 token transfers by token, specify `contractaddress` parameter
* To fetch ERC-1155 token transfers by address filtered by token, specify both `address` and `contractaddress` parameters

## Get ERC-404 token transfer events by address

`token404tx`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=token404tx
   &address={addressHash}
   &page=1
   &offset=10
   &sort=asc
```

<Tabs>
  <Tab title="Request Params">
    | Parameter       | Description                                                                                                      |
    | --------------- | ---------------------------------------------------------------------------------------------------------------- |
    | address         | required if no `contractaddress` parameter is provided, `string` containing the address hash.                    |
    | contractaddress | required if no `address` parameter is provided, `string` with the token contract address to identify a contract. |
    | sort            | optionalsorting preference, `asc` for ascending and `desc` for descending. Descending is default.                |
    | startblock      | optional `integer` block number to start transaction search                                                      |
    | endblock        | optional `integer` block number to stop transaction search.                                                      |
    | page            | optional`integer` representing the page number used for pagination. `offset` must also be provided.              |
    | offset          | optional `integer` representing number of transactions returned per page. `page` must also be provided.          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        // ERC-20 like case
        {
          "blockHash": "0x600684206fd92aa22bf0d24e376fa0433bd7247178919e31d6c8c02a8a704e78",
          "blockNumber": "22895119",
          "confirmations": "532",
          "contractAddress": "0x9e9fbde7c7a83c43913bddc8779158f1368f0413",
          "cumulativeGasUsed": "2148253",
          "from": "0x0d0707963952f2fba59dd06f2b425ace40b492fe",
          "functionName": "transfer(address to, uint256 amount)",
          "gas": "3000000",
          "gasPrice": "4992772042",
          "gasUsed": "202651",
          "hash": "0x85eba6287c25630b0f2764954e15294937ef5a423727c2236223bfb6864d2c6f",
          "input": "0xa9059cbb00000000000000000000000028e0e453997430fa2168c7efc1899a2c110e53b500000000000000000000000000000000000000000000000028536338c182e000",
          "methodId": "0xa9059cbb",
          "nonce": "8218148",
          "timeStamp": "1752227039",
          "to": "0x28e0e453997430fa2168c7efc1899a2c110e53b5",
          "tokenDecimal": "0",
          "tokenID": "",
          "tokenName": "Pandora",
          "tokenSymbol": "PANDORA",
          "transactionIndex": "44",
          "value": "2905775280000000000"
        },
        // ERC-721 like case
        {
          "blockHash": "0x600684206fd92aa22bf0d24e376fa0433bd7247178919e31d6c8c02a8a704e78",
          "blockNumber": "22895119",
          "confirmations": "532",
          "contractAddress": "0x9e9fbde7c7a83c43913bddc8779158f1368f0413",
          "cumulativeGasUsed": "2148253",
          "from": "0x0000000000000000000000000000000000000000",
          "functionName": "transfer(address to, uint256 amount)",
          "gas": "3000000",
          "gasPrice": "4992772042",
          "gasUsed": "202651",
          "hash": "0x85eba6287c25630b0f2764954e15294937ef5a423727c2236223bfb6864d2c6f",
          "input": "0xa9059cbb00000000000000000000000028e0e453997430fa2168c7efc1899a2c110e53b500000000000000000000000000000000000000000000000028536338c182e000",
          "methodId": "0xa9059cbb",
          "nonce": "8218148",
          "timeStamp": "1752227039",
          "to": "0x28e0e453997430fa2168c7efc1899a2c110e53b5",
          "tokenDecimal": "0",
          "tokenID": "97956",
          "tokenName": "Pandora",
          "tokenSymbol": "PANDORA",
          "transactionIndex": "44",
          "value": ""
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

**Usage:**

* To fetch ERC-404 token transfers by address, specify `address` parameter
* To fetch ERC-404 token transfers by token, specify `contractaddress` parameter
* To fetch ERC-404 token transfers by address filtered by token, specify both `address` and `contractaddress` parameters

## Get token account balance for token contract address

`tokenbalance`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=tokenbalance
   &contractaddress={contractAddressHash}
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter            | Description                                                           |
    | -------------------- | --------------------------------------------------------------------- |
    | **contract address** | `string` containing the contract address hash.                        |
    | **address**          | `string` containing the account address hash to retrieve balance for. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "135499",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get list of tokens owned by address

`tokenlist`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=tokenlist
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                                   |
    | ----------- | --------------------------------------------- |
    | **address** | `string` containing the account address hash. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "balance": "135499",
          "contractAddress": "0x0000000000000000000000000000000000000000",
          "decimals": "18",
          "name": "Example Token",
          "symbol": "ET",
          "type": "ERC-20"
        },
        {
          "balance": "1",
          "contractAddress": "0x0000000000000000000000000000000000000001",
          "decimals": "18",
          "name": "Example ERC-721 Token",
          "symbol": "ET7",
          "type": "ERC-721"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get list of blocks mined by address

`getminedblocks`

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=getminedblocks
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                                                                                             |
    | ----------- | ------------------------------------------------------------------------------------------------------- |
    | **address** | `string` containing the address hash.                                                                   |
    | page        | optional `integer` representing the page number used for pagination. 'offset' must also be provided.    |
    | offset      | optional `integer` representing number of transactions returned per page. `page` must also be provided. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "blockNumber": "3462296",
          "blockReward": "5194770940000000000",
          "timeStamp": "1491118514"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get a list of accounts and their balances

`listaccounts`

Lists accounts and native balances, sorted ascending by the time they were first seen by the explorer.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=account
   &action=listaccounts
   &address={addressHash}
   &page=1
   &offset=3
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                                                                                             |
    | --------- | ------------------------------------------------------------------------------------------------------- |
    | page      | optional `integer` representing the page number used for pagination. 'offset' must also be provided.    |
    | offset    | optional `integer` representing number of transactions returned per page. `page` must also be provided. |

    <Info>
      If the balance hasn't been updated in a long time, the node is double checked to fetch the absolute latest balance. This is not reflected in the current request, but once it is updated, subsequent requests will show the updated balance. The `stale` attribute will be set to `true` if a new balance is being fetched.
    </Info>
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "address": "0x3870c57fbf1d7e49b154269331c7bc66c64d8857",
          "balance": "3790064387342000000",
          "stale": false
        },
        {
          "address": "0x497d69ae30d7cca0aa84d647c6d85a59a82c16ef",
          "balance": "2047176464264000000",
          "stale": false
        },
        {
          "address": "0x9233042b8e9e03d5dc6454bbbe5aee83818ff103",
          "balance": "444111960222208758647",
          "stale": false
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>


# Block
Source: https://docs.blockscout.com/devs/apis/rpc/block

?module=block

### `https://instance_base_url/api?module=block`

## Get block reward by block number

`getblockreward`

Returns the block reward and 'uncle' block rewards when applicable.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=block
   &action=getblockreward
   &blockno={blockNumber}
```

<Tabs>
  <Tab title="Request Param">
    | Parameter | Description                                                     |
    | --------- | --------------------------------------------------------------- |
    | blockno   | `integer` block number to check block rewards for eg. `2165403` |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "blockMiner": "0x13a06d3dfe21e0db5c016c03ea7d2509f7f8d1e3",
        "blockNumber": "2165403",
        "blockReward": "5314181600000000000",
        "timeStamp": "1472533979",
        "uncleInclusionReward": null,
        "uncles": null
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get estimated block countdown time by block number

`getblockcountdown`

Returns the estimated time remaining, in seconds, until a certain block is included in blockchain.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=block
   &action=getblockcountdown
   &blockno={blockNumber}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                                                     |
    | --------- | --------------------------------------------------------------- |
    | blockno   | `integer` block number to check block rewards for eg. `2165403` |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "CurrentBlock": "115334213",
        "CountdownBlock": "116015880",
        "RemainingBlock": "681667",
        "EstimateTimeInSec": "1363349.0"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get block number by time stamp

`getblocknobytime`

Returns the block number created closest to a provided timestamp.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=block
   &action=getblocknobytime
   &timestamp={blockTimestamp}
   &closest={before/after}
```

<Tabs>
  <Tab title="Request Param">
    | Parameter | Description                                                          |
    | --------- | -------------------------------------------------------------------- |
    | timestamp | `integer` representing the Unix timestamp in seconds.                |
    | closest   | closest block to the provided timestamp, either `before` or `after`. |

    Note: [How to convert date/time to a Unix timestamp](https://www.unixtimestamp.com/).
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
       "message":"OK",
       "result":{
          "blockNumber":"23592675"
       },
       "status":"1"
    }
    ```
  </Tab>
</Tabs>

## Get the latest block number

`eth_block_number`

Mimics Ethereum JSON RPC's eth\_blockNumber.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=block
   &action=eth_block_number
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                                                           |
    | --------- | --------------------------------------------------------------------- |
    | id        | optional nonnegative integer that represents the json rpc request id. |

    More on [json rpc request id](https://www.jsonrpc.org/specification).
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "jsonrpc": "2.0",
      "result": "0x103538a",
      "id": 1
    }
    ```
  </Tab>
</Tabs>


# Contract
Source: https://docs.blockscout.com/devs/apis/rpc/contract

?module=contract

### `https://instance_base_url/api?module=contract`

## Get a list of contracts

`listcontracts`

List sorted in ascending order based on the time a contact was first indexed by the explorer. With filters \`unverified(2)\` the results will not be sorted for performance reasons.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=contract
   &action=listcontracts
```

<Tabs>
  <Tab title="Request Param">
    | Parameter                      | Description                                                                                                                    |
    | ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------ |
    | page                           | optional nonnegative `integer` representing the page number used for pagination. 'offset' must also be provided.               |
    | offset                         | optional nonnegative `integer` representing the max number of records to return when paginating. 'page' must also be provided. |
    | filter                         | optional string `verified`\|`unverified`\|`empty`, or `1`\|`2`\|`3` respectively. Returns contracts with the requested status. |
    | verified\_at\_start\_timestamp | optional `unix timestamp` Represents the starting timestamp for verified contracts. Only used with `verified` filter.          |
    | verified\_at\_end\_timestamp   | optional `unix timestamp` Represents the ending timestamp for verified contracts. Only used with `verified` filter.            |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "ABI": "[{\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event\"\n}, {\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event2\"\n}, {\n\"type\":\"function\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\"}],\n\"name\":\"foo\",\n\"outputs\": []\n}]\n",
          "CompilerVersion": "v0.2.1-2016-01-30-91a6b35",
          "ContractName": "Test",
          "OptimizationUsed": "1",
          "SourceCode": "pragma solidity >0.4.24;\n\ncontract Test {\nconstructor() public { b = hex\"12345678901234567890123456789012\"; }\nevent Event(uint indexed a, bytes32 b);\nevent Event2(uint indexed a, bytes32 b);\nfunction foo(uint a) public { emit Event(a, b); }\nbytes32 b;\n}\n"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get ABI for a verified contract

`getabi`

Also available through a GraphQL `addresses` query.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=contract
   &action=getabi
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter   | Description                           |
    | ----------- | ------------------------------------- |
    | **address** | `string` containing the address hash. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "[{\"constant\":false,\"inputs\":[{\"name\":\"voucher_token\",\"type\":\"bytes32\"}],\"name\":\"burn\",\"outputs\":[{\"name\":\"success\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"voucher_token\",\"type\":\"bytes32\"}],\"name\":\"is_expired\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"voucher_token\",\"type\":\"bytes32\"}],\"name\":\"is_burnt\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[{\"name\":\"voucher_token\",\"type\":\"bytes32\"},{\"name\":\"_lifetime\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"}]",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get contract source code for a verified contract

`getsourcecode`

Also available through a GraphQL `addresses` query.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=contract
   &action=getsourcecode
   &address={addressHash}
```

<Tabs>
  <Tab title="Request Param">
    | Parameter   | Description                           |
    | ----------- | ------------------------------------- |
    | **address** | `string` containing the address hash. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "ABI": "[{\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event\"\n}, {\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event2\"\n}, {\n\"type\":\"function\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\"}],\n\"name\":\"foo\",\n\"outputs\": []\n}]\n",
        "CompilerVersion": "v0.2.1-2016-01-30-91a6b35",
        "ContractName": "Test",
        "FileName": "{sourcify path or empty}",
        "ImplementationAddress": "0x000000000000000000000000000000000000000e",
        "IsProxy": "true",
        "OptimizationUsed": "1",
        "SourceCode": "pragma solidity >0.4.24;\n\ncontract Test {\nconstructor() public { b = hex\"12345678901234567890123456789012\"; }\nevent Event(uint indexed a, bytes32 b);\nevent Event2(uint indexed a, bytes32 b);\nfunction foo(uint a) public { emit Event(a, b); }\nbytes32 b;\n}\n"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get contract creator address hash and creation transaction hash

`getcontractcreation`

Returns contract creator and transaction hash. Up to 10 contracts at the one request

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=contract
   &action=getcontractcreation
   &contractaddresses={addressHash},{addressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter             | Description                                          |
    | --------------------- | ---------------------------------------------------- |
    | **contractaddresses** | `string` containing address hashes, separated by `,` |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "contractAddress": "0xdc2082945d55596bf39f362d9ec0f7f65edbb9dd",
          "contractCreator": "0xbb36c792b9b45aaf8b848a1392b0d6559202729e",
          "txHash": "0xe79426c9a5560cfbd78d0ef058e455c94483224ec265475583ff01ebdedceaf2"
        },
        {
          "contractAddress": "0x1b02da8cb0d097eb8d57a175b88c7d8b47997506",
          "contractCreator": "0xf87bc5535602077d340806d71f805ea9907a843d",
          "txHash": "0xe54bf38dfad760b8f96a76d8136d6540d74b02dafb5781746bf705bf7e647a3b"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Verify a contract with its source code and contract creation information

`verify`

**Example:**

```text theme={null}
https://instance_base_url/api
   ?module=contract
   &action=verify
   &addressHash={addressHash}
   &name={name}
   &compilerVersion={compilerVersion}
   &optimization={false}
   &contractSourceCode={contractSourceCode}
```

**Curl Post Example**

```sh theme={null}
curl -d '{"addressHash":"0xc63BB6555C90846afACaC08A0F0Aa5caFCB382a1","compilerVersion":"v0.5.4+commit.9549d8ff", "contractSourceCode":"pragma solidity ^0.5.4; contract Test { }","name":"Test","optimization":false}' -H "Content-Type: application/json" -X POST "https://blockscout.com/poa/sokol/api?module=contract&action=verify"
```

<Info>
  On successful submission you will receive a guid as a receipt. Use this with [`checkverifystatus`](/devs/apis/rpc/contract#return-status-of-a-verification-attempt)`to view verification status.`
</Info>

<Tabs>
  <Tab title="Params">
    | Parameter                      | Description                                                                   |
    | ------------------------------ | ----------------------------------------------------------------------------- |
    | **addressHash**                | `string` containing the address hash of the contract.                         |
    | **name**                       | `string` containing the name of the contract.                                 |
    | **compilerVersion**            | `string` containing the compiler version for the contract.                    |
    | **optimization**               | `enum` whether or not compiler optimizations were enabled `0`=false, `1`=true |
    | **contractSourceCode**         | `string` containing the source code of the contract.                          |
    | constructorArguments           | optional `string` constructor argument data provided.                         |
    | autodetectConstructorArguments | optional `boolean` whether or not automatically detect constructor argument.  |
    | evmVersion                     | optional EVM version for the contract.                                        |
    | optimizationRuns               | optional number of optimization runs used during compilation                  |
    | library1Name                   | optional `string` name of the first library used.                             |
    | library1Address                | optional `string` address of the first library used.                          |
    | library2Name                   | optional `string` name of the second library used.                            |
    | library2Address                | optional `string` address of the second library used.                         |
    | library3Name                   | optional `string` name of the third library used.                             |
    | library3Address                | optional `string` address of the third library used.                          |
    | library4Name                   | optional `string` name of the fourth library used.                            |
    | library4Address                | optional `string` address of the fourth library used.                         |
    | library5Name                   | optional `string` name of the fifth library used.                             |
    | library5Address                | optional `string` address of the fifth library used.                          |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "ABI": "[{\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event\"\n}, {\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event2\"\n}, {\n\"type\":\"function\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\"}],\n\"name\":\"foo\",\n\"outputs\": []\n}]\n",
        "CompilerVersion": "v0.2.1-2016-01-30-91a6b35",
        "ContractName": "Test",
        "ImplementationAddress": "0x000000000000000000000000000000000000000e",
        "IsProxy": "true",
        "OptimizationUsed": "1",
        "SourceCode": "pragma solidity >0.4.24;\n\ncontract Test {\nconstructor() public { b = hex\"12345678901234567890123456789012\"; }\nevent Event(uint indexed a, bytes32 b);\nevent Event2(uint indexed a, bytes32 b);\nfunction foo(uint a) public { emit Event(a, b); }\nbytes32 b;\n}\n"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Verify a contract through [Sourcify](https://sourcify.dev/)

`verify_via_sourcify`

1. if a smart contract is already verified on Sourcify, it will automatically fetch the data from the [repo](https://repo.sourcify.dev/)

2. otherwise you need to upload source files and JSON metadata file(s).

**Example:**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=verify_via_sourcify
 &addressHash={addressHash}
```

#### POST body example

```text theme={null}
--6e1e4c11657c62dc1e4349d024de9e28
Content-Disposition: form-data; name="addressHash"

0xb77b7443e0F32F1FEBf0BE0fBd7124D135d0a525

--6e1e4c11657c62dc1e4349d024de9e28
Content-Disposition: form-data; name="files[0]"; filename="contract.sol"
Content-Type: application/json

...Source code...

--6e1e4c11657c62dc1e4349d024de9e28
Content-Disposition: form-data; name="files[1]"; filename="metadata.json"
Content-Type: application/json

...JSON metadata...

--6e1e4c11657c62dc1e4349d024de9e28--
```

<Tabs>
  <Tab title="Params">
    | Parameter       | Description                             |
    | --------------- | --------------------------------------- |
    | **addressHash** | `string` containing the address hash.   |
    | files           | `array` with sources and metadata files |
  </Tab>

  <Tab title="Example">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "ABI": "[{\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event\"\n}, {\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event2\"\n}, {\n\"type\":\"function\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\"}],\n\"name\":\"foo\",\n\"outputs\": []\n}]\n",
        "CompilerVersion": "v0.2.1-2016-01-30-91a6b35",
        "ContractName": "Test",
        "ImplementationAddress": "0x000000000000000000000000000000000000000e",
        "IsProxy": "true",
        "OptimizationUsed": "1",
        "SourceCode": "pragma solidity >0.4.24;\n\ncontract Test {\nconstructor() public { b = hex\"12345678901234567890123456789012\"; }\nevent Event(uint indexed a, bytes32 b);\nevent Event2(uint indexed a, bytes32 b);\nfunction foo(uint a) public { emit Event(a, b); }\nbytes32 b;\n}\n"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Verify a vyper contract with its source code and contract creation information

`verify_vyper_contract`

**Example**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=verify_vyper_contract
 &addressHash={addressHash}
 &name={name}
 &compilerVersion={compilerVersion}
 &contractSourceCode={contractSourceCode}
```

**curl POST example**

```powershell theme={null}
curl --location --request POST 'http://localhost:4000/api?module=contract&action=verify_vyper_contract' --form 'contractSourceCode="SOURCE_CODE"' --form 'name="Vyper_contract"' --form 'addressHash="0xE60B1B8bD493569a3E945be50A6c89d29a560Fa1"' --form 'compilerVersion="v0.2.12"'
```

<Tabs>
  <Tab title="First Tab">
    | Parameter              | Description                                                |
    | ---------------------- | ---------------------------------------------------------- |
    | **addressHash**        | `string` containing the address hash of the contract.      |
    | **name**               | `string` containing the name of the contract.              |
    | **compilerVersion**    | `string` containing the compiler version for the contract. |
    | **contractSourceCode** | `string` containing the source code of the contract.       |
    | constructorArguments   | `string` constructor argument data provided.               |
  </Tab>

  <Tab title="Example">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "ABI": "[{\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event\"\n}, {\n\"type\":\"event\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\",\"indexed\":true},{\"name\":\"b\",\"type\":\"bytes32\",\"indexed\":false}],\n\"name\":\"Event2\"\n}, {\n\"type\":\"function\",\n\"inputs\": [{\"name\":\"a\",\"type\":\"uint256\"}],\n\"name\":\"foo\",\n\"outputs\": []\n}]\n",
        "CompilerVersion": "v0.2.1-2016-01-30-91a6b35",
        "ContractName": "Test",
        "ImplementationAddress": "0x000000000000000000000000000000000000000e",
        "IsProxy": "true",
        "OptimizationUsed": "1",
        "SourceCode": "pragma solidity >0.4.24;\n\ncontract Test {\nconstructor() public { b = hex\"12345678901234567890123456789012\"; }\nevent Event(uint indexed a, bytes32 b);\nevent Event2(uint indexed a, bytes32 b);\nfunction foo(uint a) public { emit Event(a, b); }\nbytes32 b;\n}\n"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Verify a contract with Standard input JSON file

`verifysourcecode`

**Example**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=verifysourcecode
 &codeformat={solidity-standard-json-input}
 &contractaddress={contractaddress}
 &contractname={contractname}
 &compilerversion={compilerversion}
 &sourceCode={sourceCode}
```

`solidity-single-file`:

```sh theme={null}
curl --location 'localhost:4000/api?module=contract&action=verifysourcecode' \
--form 'contractaddress="0xDc2082945d55596bf39F362d9EC0F7F65eDBB9DD"' \
--form 'sourceCode="// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.7.0 <0.9.0;

contract Storage {
    uint256 number;

    function store(uint256 num) public {
        number = num;
    }

    function retrieve() public view returns (uint256){
        return number;
    }
}"' \
--form 'contractname="Storage"' \
--form 'codeformat="solidity-single-file"' \
--form 'compilerversion="v0.8.17+commit.8df45f5f"' \
--form 'optimizationUsed="1"' \
--form 'runs="199"' \
--form 'constructorArguements=""' \
--form 'evmversion="london"' \
--form 'libraryname1="qwe"' \
--form 'libraryaddress1="0xDc2082945d55596bf39F362d9EC0F7F65eDBB9DD"'
--form 'licenseType=0'
```

<Tabs>
  <Tab title="Params">
    | Parameter                      | Description                                                                                                                                                                    |
    | ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
    | **codeformat**                 | Format of sourceCode (`solidity-standard-json-input` or `solidity-single-file`)                                                                                                |
    | **contractaddress**            | `string` containing the address hash of the contract.                                                                                                                          |
    | **contractname**               | `string` name of the contract. It an be an empty string(""), just the contract name("ContractName"), or a filename and contract name("contracts/contract\_1.sol:ContractName") |
    | **compilerversion**            | `string` containing the compiler version for the contract.                                                                                                                     |
    | **sourceCode**                 | `string` standard input json or flattened solidity code                                                                                                                        |
    | optimizationUsed               | could be `0`, `false`, `1`, `true`. Should be set when `codeformat=solidity-single-file`                                                                                       |
    | runs                           | `integer` is equal to optimization runs number set on compilation. Should be set when `optimizationUsed` is `1` or `true`                                                      |
    | evmversion                     | `string` EVM version. Should be set when `codeformat=solidity-single-file`                                                                                                     |
    | constructorArguments           | optional `string` constructor argument data provided.                                                                                                                          |
    | autodetectConstructorArguments | optional `boolean` whether or not automatically detect constructor argument.                                                                                                   |
    | licenseType                    | `string` or `number` representing the license type.                                                                                                                            |

    **License type**

    "See [available license types](/devs/verification/blockscout-smart-contract-verification-api)."
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "b080b96bd06ad1c9341c2afb7e3730311388544961acde94",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Return status of a verification attempt

`checkverifystatus`

<Info>
  guid is received as a receipt from the `verifysourcecode` method.
</Info>

**Example**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=checkverifystatus
 &guid={identifierString}
```

<Tabs>
  <Tab title="Params">
    | Parameter | Description                                       |
    | --------- | ------------------------------------------------- |
    | **guid**  | `string`used for identifying verification attempt |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "Pending in queue",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

<Info>
  Return Options: `Pending in queue` | `Pass - Verified` | `Fail - Unable to verify` | `Unknown UID`
</Info>

## Verify proxy contract

`verifyproxycontract`

**Example**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=verifyproxycontract
 &address={addressHash}
```

<Tabs>
  <Tab title="Params">
    | Parameter   | Description                                          |
    | ----------- | ---------------------------------------------------- |
    | **address** | `string` containing the address hash of the contract |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
        "message": "OK",
        "result": "c32d204404f33ff38fee42394f7e671fd96314b3658d466a",
        "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Return status of a proxy contract verification attempt

`checkproxyverification`

<Info>
  guid is received as a receipt from the `verifyproxycontract` method.
</Info>

**Example**

```javascript theme={null}
https://instance_base_url/api
 ?module=contract
 &action=checkproxyverification
 &guid={identifierString}
```

<Tabs>
  <Tab title="Params">
    | Parameter | Description                                       |
    | --------- | ------------------------------------------------- |
    | **guid**  | `string`used for identifying verification attempt |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "Implementation (0x5a3f40fd57731bbf62a38fd290add074e9cdb844) was verified and saved for proxy (0xc32d204404f33ff38fee42394f7e671fd96314b3)",
      "status": "1"
    }
    ```

    <Info>
      Return Options:

      * `Verification in progress`

      * `The proxy's ({addressHash}) implementation contract is found at {addressHash} and is successfully updated.`

      * `A corresponding implementation contract was unfortunately not detected for the proxy address.`

      * `Unknown UID`
    </Info>
  </Tab>
</Tabs>


# ETH RPC API
Source: https://docs.blockscout.com/devs/apis/rpc/eth-rpc



In addition to the custom [RPC endpoints documented here](/devs/apis/rpc), the Blockscout ETH RPC API supports most used methods in the exact format specified for Ethereum nodes, see the [Ethereum JSON-RPC Specification](https://ethereum.github.io/execution-apis/api-documentation/) for more details.

These methods are provided for your convenience and are most suitable as a fallback option in your JSON RPC API providers. For other use cases, REST or custom RPC methods are recommended.

The following methods are supported:

* eth\_blockNumber

* eth\_getBalance

* eth\_getLogs

* eth\_gasPrice

* eth\_getTransactionByHash

* eth\_getTransactionReceipt

* eth\_chainId

* eth\_maxPriorityFeePerGas

* eth\_getTransactionCount

* eth\_getCode

* eth\_getStorageAt

* eth\_estimateGas

* eth\_getBlockByNumber

* eth\_getBlockByHash

* eth\_sendRawTransaction

* eth\_call

In the following examples we use the Ethereum mainnet with the base instance url `https://eth.blockscout.com`. When sending a request add `/api/eth-rpc` to the end of the base url.

## eth\_blockNumber

Returns the latest block number in the chain in hexadecimal format. No params are needed. Type: POST

**Example**

```swift theme={null}
// Request
curl -H "content-type: application/json" -X POST --data '{"id":0,"jsonrpc":"2.0","method":"eth_blockNumber","params":[]}' https://eth.blockscout.com/api/eth-rpc
// Response
{
  "jsonrpc": "2.0",
  "result": "0xfa0b0e",
  "id": 0
}
```

## eth\_getBalance

Returns the balance of a given address in wei. Note the `earliest` parameter does not work as expected because genesis block balances are not currently imported. Parameters are required.

**Required Parameters**

|                          |                                                                               |
| ------------------------ | ----------------------------------------------------------------------------- |
| Type                     | POST                                                                          |
| Data (string)            | 20 Byte address to check balance                                              |
| Quantity or Tag (string) | Integer value of a block number, or a tag "latest" for the most recent block. |

**Example**

```swift theme={null}
// Request
curl -H "content-type: application/json" -X POST --data '{"id":0,"jsonrpc":"2.0","method":"eth_getBalance","params":["0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045","latest"]}' https://eth.blockscout.com/api/eth-rpc
// Response
{
  "jsonrpc": "2.0",
  "result": "0x1d863bf76508104fb", //34039260923474019579
  "id": 0
}
```

## eth\_getLogs

Returns an array of logs matching a specified filter object. Params are optional based on data you want to receive. From more information, see this [post on eth\_getLogs](https://medium.com/alchemy-api/deep-dive-into-eth-getlogs-5faf6a66fd81).

Note: Never returns more than 1000 log entries. You can use pagination options to request the next page. Pagination options params: \{"logIndex": "3D", "blockNumber": "6423AC"} which include parameters from the last log received from the previous request. These three parameters are required for pagination.

**Parameters**

|                            |                                                                                                                                  |
| -------------------------- | -------------------------------------------------------------------------------------------------------------------------------- |
| Type                       | POST                                                                                                                             |
| `address` (string, array)  | 20Byte contract address or list of addresses to collect logs from.                                                               |
| `fromBlock` (Quantity/Tag) | Integer block number, `"latest"` (default) for the last mined block or `"pending"`, `"earliest"` for not yet mined transactions. |
| `toBlock` (Quantity/Tag)   | Integer block number, `"latest"`                                                                                                 |


# Logs
Source: https://docs.blockscout.com/devs/apis/rpc/logs

?module=logs

### `https://instance_base_url/api?module=logs`

## Get Event Logs by Address and/or Topic(s)

`getLogs`

Event logs for an address and topic. Use **and/or** with the topic operator to specify topic retrieval options when adding multiple topics. Up to a maximum of 1,000 event logs.

**Example:**

```javascript theme={null}
https://instance_base_url/api
   ?module=logs
   &action=getLogs
   &fromBlock=1379224
   &toBlock=13792288
   &address=0x33990122638b9132ca29c723bdf037f1a891a70c
   &topic0=0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545
   &topic1=0x72657075746174696f6e00000000000000000000000000000000000000000000
   &topic0_1_opr=or
```

*\*=required field*

<Tabs>
  <Tab title="Request Params">
    | Parameter      | Description                                                                                                                                          |
    | -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- |
    | fromBlock\*    | `integer` block number to start searching for logs. `latest` is also supported                                                                       |
    | toBlock\*      | `integer` block number to stop searching for logs. `latest` is also supported. *Note can be same as fromBlock if looking at logs for a single block* |
    | address\*      | `string` 160-bit code used for identifying contracts. An address and/or topic is required.                                                           |
    | topic0\*       | `string` for first required topic.                                                                                                                   |
    | topic1         | `string` for 2nd optional topic.                                                                                                                     |
    | topic2         | `string` for 3rd optional topic.                                                                                                                     |
    | topic3         | `string` for 4th optional topic.                                                                                                                     |
    | topic0\_1\_opr | operator when topic 0 and 1 are used. Either `and` or `or`                                                                                           |
    | topic0\_2\_opr | operator for topic 0 and topic 2. Either `and` or `or`                                                                                               |
    | topic0\_3\_opr | operator for topic 0 and topic 3. Either `and` or `or`                                                                                               |
    | topic1\_2\_opr | operator for topic 1 and topic 2. Either `and` or `or`                                                                                               |
    | topic1\_3\_opr | the topic operator for topic 1 and topic 3. Either `and` or `or`                                                                                     |
    | topic2\_3\_opr | the topic operator for topic 2 and topic 3. Either `and` or `or`                                                                                     |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "address": "0x33990122638b9132ca29c723bdf037f1a891a70c",
          "blockNumber": "0x5c958",
          "data": "0x",
          "gasPrice": "0xba43b7400",
          "gasUsed": "0x10682",
          "logIndex": "0x",
          "timeStamp": "0x561d688c",
          "topics": [
            "0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
            "0x72657075746174696f6e00000000000000000000000000000000000000000000",
            "0x000000000000000000000000d9b2f59f3b5c7b3c67047d2f03c3e8052470be92"
          ],
          "transactionHash": "0x0b03498648ae2da924f961dda00dc6bb0a8df15519262b7e012b7d67f4bb7e83",
          "transactionIndex": "0x"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>


# Stats
Source: https://docs.blockscout.com/devs/apis/rpc/stats

?module=stats

### `https://instance_base_url/api?module=stats`

## Get [ERC-20](https://github.com/ethereum/EIPs/issues/20) or [ERC-721](https://github.com/ethereum/EIPs/issues/721) token total supply by contract address

`tokensupply`

**Example**

```javascript theme={null}
https://instance_base_url/api
   ?module=stats
   &action=tokensupply
   &contractaddress={contractAddressHash}
```

<Tabs>
  <Tab title="Request Param">
    | Parameter       | Description                                                                                    |
    | --------------- | ---------------------------------------------------------------------------------------------- |
    | contractaddress | `string` containing the contract address hash - a 160-bit code used for identifying contracts. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": "21265524714464",
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get total supply in Wei from exchange

`ethsupplyexchange`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Param">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>

## Get total supply in Wei from DB

`ethsupply`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>

## Get total coin supply from DB minus burnt number

`coinsupply`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>

## Get latest price of native coin in USD and BTC

`ethprice`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>

## Get latest price of native coin in USD and BTC in more general format

`coinprice`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>

## Get total transaction fees in Wei paid by users to validators per day

`totalfees`

**Example:**

```javascript theme={null}
// Some code
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description |
    | --------- | ----------- |
    | param     | description |
  </Tab>

  <Tab title="Example Result">
    ```javascript theme={null}
    // Some code
    ```
  </Tab>
</Tabs>


# Token
Source: https://docs.blockscout.com/devs/apis/rpc/token

?module=token

### `https://instance_base_url/api?module=token`

## Get ERC-20 or ERC-721 token by contract address

`getToken`

Info on name, symbol, supply and type for a token contract address.

**Example**

```javascript theme={null}
https://instance_base_url/api
   ?module=token
   &action=getToken
   &contractaddress={contractaddressHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter       | Description                                                                                    |
    | --------------- | ---------------------------------------------------------------------------------------------- |
    | contractaddress | `string` containing the contract address hash - a 160-bit code used for identifying contracts. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "cataloged": true,
        "contractAddress": "0x0000000000000000000000000000000000000000",
        "decimals": "18",
        "name": "Example Token",
        "symbol": "ET",
        "totalSupply": "1000000000",
        "type": "ERC-20"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get token holders by contract address

`getTokenHolders`

Returns an array of token holder's accounts and amounts held for a specified token contract address.

**Example**

```text theme={null}
https://instance_base_url/api
   ?module=token
   &action=getTokenHolders
   &contractaddress={contractaddressHash}
   &page={integer}
   &offset={integer}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter       | Description                                                                                                                    |
    | --------------- | ------------------------------------------------------------------------------------------------------------------------------ |
    | contractaddress | `string` containing the contract address hash of the ERC-20/ERC-721 token                                                      |
    | page            | optional nonnegative `integer` representing the page number used for pagination. 'offset' must also be provided.               |
    | offset          | optional nonnegative `integer` representing the max number of records to return when paginating. 'page' must also be provided. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "address": "0x3887e82dbdbe8ec6db44e6298a2d48af572a3b78",
          "value": "153737849289497644937838"
        },
        {
          "address": "0xc894c5de34cb2a3615c737d1276876e44e9700a3",
          "value": "77247336418828547887499"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get bridged tokens list

`bridgedTokenList`

Returns an array of bridged token information (uses native bridge application and only returns when applicable - depends on implementation).

**Example**

```text theme={null}
https://instance_base_url/api
   ?module=token
   &action=bridgedTokenList
   &chainid={chainid}
   &page={integer}
   &offset={integer}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                                                                                                                    |
    | --------- | ------------------------------------------------------------------------------------------------------------------------------ |
    | chainID   | nonnegative `integer` that represents the chain id where the original token exists.                                            |
    | page      | optional nonnegative `integer` representing the page number used for pagination. 'offset' must also be provided.               |
    | offset    | optional nonnegative `integer` representing the max number of records to return when paginating. 'page' must also be provided. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": [
        {
          "foreignChainId": "1",
          "foreignTokenContractAddressHash": "0x0ae055097c6d159879521c384f1d2123d1f195e6",
          "homeContractAddressHash": "0xb7d311e2eb55f2f68a9440da38e7989210b9a05e",
          "homeDecimals": "18",
          "homeHolderCount": 393,
          "homeName": "STAKE on xDai",
          "homeSymbol": "STAKE",
          "homeTotalSupply": "1484374.775044204093387391",
          "homeUsdValue": "18807028.39981006586321824397"
        },
        {
          "foreignChainId": "1",
          "foreignTokenContractAddressHash": "0xf5581dfefd8fb0e4aec526be659cfab1f8c781da",
          "homeContractAddressHash": "0xd057604a14982fe8d88c5fc25aac3267ea142a08",
          "homeDecimals": "18",
          "homeHolderCount": 73,
          "homeName": "HOPR Token on xDai",
          "homeSymbol": "HOPR",
          "homeTotalSupply": "26600449.86076749062791602",
          "homeUsdValue": "6638727.472651464170990256943"
        }
      ],
      "status": "1"
    }
    ```
  </Tab>
</Tabs>


# Transaction
Source: https://docs.blockscout.com/devs/apis/rpc/transaction

?module=transaction

### `https://instance_base_url/api?module=transaction`

## Get transaction info

`gettxinfo`

Information related to a specified transaction. Includes:

* blockNumber

* confirmations

* from

* gasLimit (in wei)

* gasPrice (in wei)

* gasUsed

* hash

* input

* logs (array)

* revert reason

* success

* timeStamp

* to

* value (in wei)

**Example**

```javascript theme={null}
https://instance_base_url/api
   ?module=transaction
   &action=gettxinfo
   &txhash={transactionHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                                                                       |
    | --------- | --------------------------------------------------------------------------------- |
    | txhash    | `string` containing the transaction hash                                          |
    | index     | optional nonnegative `integer` that represents the log index used for pagination. |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "result": {
        "revertReason": "No credit of that type",
        "blockNumber": "3",
        "confirmations": "0",
        "from": "0x000000000000000000000000000000000000000c",
        "gasLimit": "91966",
        "gasPrice": "100000",
        "gasUsed": "95123",
        "hash": "0x0000000000000000000000000000000000000000000000000000000000000004",
        "input": "0x04",
        "logs": [
          {
            "address": "0x000000000000000000000000000000000000000e",
            "data": "0x00",
            "topics": [
              "First Topic",
              "Second Topic",
              "Third Topic",
              "Fourth Topic"
            ]
          }
        ],
        "success": true,
        "timeStamp": "1541018182",
        "to": "0x000000000000000000000000000000000000000d",
        "value": "67612"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get transaction receipt status

`gettxreceiptstatus`

Also available through a GraphQL 'transaction' query. `Status` field return:

* `0` = failed transaction

* `1` = successful transaction

**Example**

```text theme={null}
https://instance_base_url/api
   ?module=transaction
   &action=gettxreceiptstatus
   &txhash={transactionHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                              |
    | --------- | ---------------------------------------- |
    | txhash    | `string` containing the transaction hash |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "status": "1"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>

## Get error status and message

`getstatus`

Also available through a GraphQL 'transaction' query. Includes the following:

* errDescription: string with error message

* isError

  * 0 = pass, no error

  * 1 = error

**Example**

```javascript theme={null}
https://instance_base_url/api
   ?module=transaction
   &action=getstatus
   &txhash={transactionHash}
```

<Tabs>
  <Tab title="Request Params">
    | Parameter | Description                              |
    | --------- | ---------------------------------------- |
    | txhash    | `string` containing the transaction hash |
  </Tab>

  <Tab title="Example Result">
    ```json theme={null}
    {
      "message": "OK",
      "result": {
        "errDescription": "Out of gas",
        "isError": "1"
      },
      "status": "1"
    }
    ```
  </Tab>
</Tabs>


# Blockscout SDK
Source: https://docs.blockscout.com/devs/blockscout-sdk



<Info>
  Attention ETHGlobal Hackathon Participants. We have a $3000 Bounty available for best SDK Usage (1 $2000 prize and 1 \$1000 prize). Add the Blockscout SDK into your app to provide interactivity and instant explorer feedback to your users.

  Note: The Blockscout SDK is currently in beta release. Please report any issues on the [Blockscout Discord](https://discord.gg/blockscout).
</Info>

## Overview

The Blockscout App SDK is a React toolkit designed to integrate Blockscout transaction notifications and transaction history into your decentralized applications (dApps). It provides an easy-to-use interface for displaying transaction status updates and viewing transaction history with real-time updates and mobile-responsive design.

<Check>
  * Repo: [https://github.com/blockscout/app-sdk](https://github.com/blockscout/app-sdk)

  * NPM Package [https://www.npmjs.com/package/@blockscout/app-sdk](<https://www.npmjs.com/package/@blockscout/app-sdk >)
</Check>

### Key Features

* **Transaction Toast Notifications** - Real-time transaction status updates with pending, success, and error states

* **Transaction History Popup** - View recent transactions for specific addresses or entire chains

* **Transaction Interpretation** - Detailed transaction summaries and interpretations

* **Multi-chain Support** - Compatible with any blockchain that has a Blockscout explorer instance

* **Mobile-responsive Design** - Optimized for both desktop and mobile experiences

### Installation

Install the SDK using npm or yarn:

```sh theme={null}
npm install @blockscout/app-sdk
# or
yarn add @blockscout/app-sdk
```

### Transaction Toast Notifications

The transaction toast feature provides real-time notifications for transaction status updates, showing pending, success, and error states with detailed transaction information.

#### Setup

Wrap your application with the `NotificationProvider`:

```javascript theme={null}
import { NotificationProvider } from "@blockscout/app-sdk";

function App() {
  return (
    <NotificationProvider>
      <YourApp />
    </NotificationProvider>
  );
}
```

#### Usage

Use the `useNotification` hook to display transaction toasts:

```javascript theme={null}
import { useNotification } from "@blockscout/app-sdk";

function YourComponent() {
  const { openTxToast } = useNotification();

  const handleTransaction = async (txHash) => {
    try {
      // Your transaction logic here
      await sendTransaction();
      
      // Show transaction toast
      openTxToast("1", txHash); // '1' is the chain ID for Ethereum mainnet
    } catch (error) {
      console.error("Transaction failed:", error);
    }
  };

  return (
    <button onClick={() => handleTransaction("0x123...")}>
      Send Transaction
    </button>
  );
}
```

#### Toast Features

* Real-time status updates (pending, success, error)

* Transaction interpretation and summaries

* Links to block explorer

* Automatic status polling

* Error handling with revert reasons

### Transaction History Popup

The transaction history popup allows users to view recent transactions for a specific address or all transactions on a chain.

#### Setup

Wrap your application with the `TransactionPopupProvider`:

```javascript theme={null}
import { TransactionPopupProvider } from "@blockscout/app-sdk";

function App() {
  return (
    <TransactionPopupProvider>
      <YourApp />
    </TransactionPopupProvider>
  );
}
```

#### Usage

Use the `useTransactionPopup` hook to open transaction history:

```javascript theme={null}
import { useTransactionPopup } from "@blockscout/app-sdk";

function YourComponent() {
  const { openPopup } = useTransactionPopup();

  // Show transactions for a specific address
  const showAddressTransactions = () => {
    openPopup({
      chainId: "1", // Ethereum mainnet
      address: "0x123...", // Optional: specific address
    });
  };

  // Show all transactions for a chain
  const showAllTransactions = () => {
    openPopup({
      chainId: "1", // Ethereum mainnet
    });
  };

  return (
    <div>
      <button onClick={showAddressTransactions}>
        View Address Transactions
      </button>
      <button onClick={showAllTransactions}>
        View All Transactions
      </button>
    </div>
  );
}
```

#### Popup Features

* View recent transactions

* Filter by address

* Transaction status indicators

* Transaction interpretation

* Links to block explorer

* Mobile-responsive design

* Loading states and error handling

### Supported Chains

The SDK is compatible with any blockchain that has a Blockscout explorer instance with API v2 support.

* Chains are listed in [Chainscout](https://chains.blockscout.com/).

* Chain IDs can be retrieved from [https://github.com/blockscout/chainscout/blob/main/data/chains.json](https://github.com/blockscout/chainscout/blob/main/data/chains.json)

* To verify if your target chain ID is supported, visit the [compatibility checker](https://sdk-compatibility.blockscout.com/).

#### Common Supported Chain IDs

* `1` - Ethereum Mainnet

* `137` - Polygon Mainnet

* `42161` - Arbitrum One

* `10` - Optimism

### API Reference

#### useNotification Hook

```js theme={null}
const { openTxToast } = useNotification();

// Open a transaction toast
openTxToast(chainId: string, hash: string): Promise<void>
```

#### useTransactionPopup Hook

```js theme={null}
const { openPopup } = useTransactionPopup();

// Open transaction popup
openPopup(options: {
  chainId: string;
  address?: string;
}): void
```

### Complete Integration Example

Here's a complete example showing how to integrate both features:

```javascript theme={null}
import React from 'react';
import { 
  NotificationProvider, 
  TransactionPopupProvider,
  useNotification,
  useTransactionPopup 
} from "@blockscout/app-sdk";

function TransactionComponent() {
  const { openTxToast } = useNotification();
  const { openPopup } = useTransactionPopup();

  const sendTransaction = async () => {
    const txHash = "0x123..."; // Your transaction hash
    await openTxToast("1", txHash);
  };

  const viewHistory = () => {
    openPopup({
      chainId: "1",
      address: "0x456..." // Optional
    });
  };

  return (
    <div>
      <button onClick={sendTransaction}>Send Transaction</button>
      <button onClick={viewHistory}>View Transaction History</button>
    </div>
  );
}

function App() {
  return (
    <NotificationProvider>
      <TransactionPopupProvider>
        <TransactionComponent />
      </TransactionPopupProvider>
    </NotificationProvider>
  );
}

export default App;
```


# Chainscout Chains List
Source: https://docs.blockscout.com/devs/chainscout-chains-list

List of EVM networks supported by Blockscout

<Info>
  Chainscout is currently in Beta. Visit a live instance at [https://chains.blockscout.com/](https://chains.blockscout.com/)
</Info>

* Chainscout includes chain ids and other chain information formatted as a JSON file. Add your own chain details through a pull request.

* Visit the repository to learn more: [https://github.com/blockscout/chainscout](https://github.com/blockscout/chainscout)

* Once all chains have been added, Chainscout will replace the current Blockscout chains and projects page located at [https://www.blockscout.com/chains-and-projects](https://www.blockscout.com/chains-and-projects).


# For Web3 Developers
Source: https://docs.blockscout.com/devs/for-web3-developers



👋 Welcome Web3 Developers and hackathon participants! Blockscout is built for you and optimized for use in web3 applications.

See the categories below for more information.

<CardGroup>
  <Card href="/devs/apis">
    <img alt="" />

    Blockscout APIs
  </Card>

  <Card href="/devs/verification">
    <img alt="" />

    Smart Contract Verification Tools and Resources
  </Card>

  <Card href="/devs/replace-links">
    <img alt="" />

    Pointing links to Blockscout / Replacing Existing Links
  </Card>

  <Card href="/devs/blockscout-sdk">
    <img alt="" />

    Blockscout SDK
  </Card>

  <Card href="/devs/integrate-merits">
    <img alt="" />

    Integrate Blockscout Merits
  </Card>

  <Card href="/using-blockscout/autoscout">
    <img alt="" />

    Autoscout 5 minute cloud deployment wizard
  </Card>

  <Card href="/devs/chainscout-chains-list">
    <img alt="" />

    Chainscout EVM chains list
  </Card>
</CardGroup>

### Additional Resources

🏃🏻‍♂️ For details on developing on the Blockscout platform, advanced setup, ENVs, microservices like ENS, and Blockscout deployment please see the [Blockscout Setup](/setup/information-and-settings) section.

❔See the [Common Developer FAQs](/faqs/developer-faqs) for questions related to Blockscout development.

🙋🏽‍♀️ [Join our Discord](https://discord.gg/blockscout) for technical questions and support.


# Integrate Merits
Source: https://docs.blockscout.com/devs/integrate-merits



<Info>
  Attention ETHGlobal Hackathon Participants. We have a \$1000 Bounty available for best integration of Merits. The basic requirement is to incorporate Merits (Blockscout Points) into your application in some way. Users can earn Merits through different activities in your app and you can distribute them via the API. Below you will find more info on the program and the API for checking user Merits, distribution, and login processes.
</Info>

***

### What are Blockscout Merits?

Merits are digital rewards collected by interacting with Blockscout and Blockscout-related apps and by participating in various activities (like contests, X participation, telegram participation, app participation and more). Merits are chain agnostic and can be incorporated into any application. For more details see the [Merits section of the docs](/using-blockscout/merits).

### Using Merits as an activity incentive

Merits are used to incentivize different activities within the Blockscout universe. For example:

* **Blockscout explorer basics:** Earn Merits by signing up for the program. Once you are signed up, you can earn additional Merits by completing a daily claim. You can also share your referral code and earn Merits when new users sign up with that code.
* **Telegram mini app.** The telegram Blockscout Merits Bot allows for direct communication with subscribers. Users who download the bot receive extra Merits -> [https://t.me/blockscout\_merits\_bot](https://t.me/blockscout_merits_bot)
* **Swapscout swapping app**. Merits are incorporated in the app so that users can view their balance and earn Merits for their swaps. [https://swap.blockscout.com/](https://swap.blockscout.com/). **This is a good example of an external app that incorporates Merits.**
* **Revokescout app.** Merits are used to incentivize users but there is no sign in or interface. We simply check addresses that use the application and distribute Merits to those addresses.
* **Blockscout campaigns**. Participants in time-gated campaigns such as rating Dapps or Twitter(X) contests receive additional Merits. We collect the Ethereum addresses of winners and distribute Merits manually.
* **Partner campaigns**. Merits are allocated to users of other protocols as an additional incentive for use. Partners provide us with a list of addresses and tasks they completed and we distribute accordingly.

### Integrating Test Merits into your application

Merits can be integrated in different ways into your application. Ideas may be to include Merits as a reward for user interactions with your app or a general reward for any activity. Merits can be distributed to users via the API.

Users can have the ability to sign up for Merits through your app and/or login to their Merits account. You can also display individual Merits balances and leaderboard balances within your application. However, these are optional integrations.

To qualify for the bounty, you simply need to provide Merit incentives for certain activities, and then distribute those merits appropriately. As long as you have the participant's Ethereum address you can distribute Merits.

<Warning>
  Note: You can retrieve basic data without an API key, but **for interactivity purposes you will need to request one via our Discord channe**l. See below.
</Warning>

### Getting started

1. Request your API key at: [https://ethglobal.com/discord](https://ethglobal.com/discord) in the #partner-blockscout channel
2. API hostname (and test merits dashboard): [https://merits-staging.blockscout.com](https://merits-staging.blockscout.com)

<Info>
  A full list of endpoints is available on our swagger page here: [https://blockscout.github.io/swaggers/services/merits/main/index.html](https://blockscout.github.io/swaggers/services/merits/main/index.html)
</Info>

### Get basic Merit info for a user

`GET` `https://merits-staging.blockscout.com/api/v1/auth/user/\{address}`

Returns user information by address

**Path parameters**

<ParamField type="string">
  The blockchain address of the user
</ParamField>

**Responses**

<Accordion title="200 User Information">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="exists" type="boolean">
        Indicates if the user exists

        Example: `true`
      </ResponseField>

      <ResponseField name="user" type="object">
        <Expandable title="properties">
          <ResponseField name="address" type="string">
            The blockchain address of the user

            Example: `0x813399e5b08Bb50b038AA7dF6347b6AF2D161338`
          </ResponseField>

          <ResponseField name="total_balance" type="string">
            Merits balance

            Example: `981`
          </ResponseField>

          <ResponseField name="referrals" type="string">
            Number of invited users

            Example: `5`
          </ResponseField>

          <ResponseField name="registered_at" type="string . date-time">
            Registration timestamp

            Example: `2024-10-21T13:21:20.529Z`
          </ResponseField>
        </Expandable>
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v1/auth/user/{address} HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/api/v1/auth/user/{address}' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/auth/user/{address}', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/api/v1/auth/user/{address}",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 User Information theme={null}
{
  "exists": true,
  "user": {
    "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
    "total_balance": "981",
    "referrals": "5",
    "registered_at": "2024-10-21T13:21:20.529Z"
  }
}
```

### Get leaderboard ranking for a user

`GET` `https://merits-staging.blockscout.com/api/v1/leaderboard/users/\{address}`

Returns the leaderboard information for a specific user

**Path parameters**

<ParamField type="string">
  The blockchain address of the user
</ParamField>

**Responses**

<Accordion title="200 User leaderboard information">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="address" type="string">
        The blockchain address of the user

        Example: `0x813399e5b08Bb50b038AA7dF6347b6AF2D161338`
      </ResponseField>

      <ResponseField name="total_balance" type="string">
        The current user's balance

        Example: `981`
      </ResponseField>

      <ResponseField name="referrals" type="string">
        Number of invited users

        Example: `5`
      </ResponseField>

      <ResponseField name="registered_at" type="string . date-time">
        The date and time when the user registered

        Example: `2024-10-21T13:21:20.529Z`
      </ResponseField>

      <ResponseField name="rank" type="string">
        The rank of the user on the leaderboard

        Example: `1`
      </ResponseField>

      <ResponseField name="users_below" type="string">
        Number of users below the current user

        Example: `71569`
      </ResponseField>

      <ResponseField name="top_percent" type="number . double">
        In what percentage of users the current one is in

        Example: `0.01`
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v1/leaderboard/users/{address} HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/api/v1/leaderboard/users/{address}' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/leaderboard/users/{address}', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/api/v1/leaderboard/users/{address}",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 User leaderboard information theme={null}
{
  "address": "0x813399e5b1102950b038AA7dF6347b6AF21102828",
  "total_balance": "981",
  "referrals": "5",
  "registered_at": "2024-10-21T13:21:20.529Z",
  "rank": "1",
  "users_below": "71569",
  "top_percent": 0.01
}
```

### Partner balance and distribution information

When you request an API key you become a partner! You will receive a balance of test Merits which can then be distributed to your users.

*\* Requires API Key - Add the assigned API KEY in the Authorization header to see your information.*

`GET` `https://merits-staging.blockscout.com/partner/api/v1/balance`

Returns the balance and distribution information for a partner

**Responses**

<Accordion title="200 Partner balance information">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="name" type="string">
        Partner name

        Example: `partner-1`
      </ResponseField>

      <ResponseField name="api_key" type="string">
        API key for the partner

        Example: `4VF6LDF7RC64CNGWXOECF8J1LJ62W5HS`
      </ResponseField>

      <ResponseField name="valid_since" type="string . date-time">
        Merits accrual start date

        Example: `2025-05-01T00:00:00.000Z`
      </ResponseField>

      <ResponseField name="valid_until" type="string . date-time">
        Merits accrual end date

        Example: `2025-06-01T00:00:00.000Z`
      </ResponseField>

      <ResponseField name="rate" type="string">
        Amount of accruing merits per second

        Example: `0.1`
      </ResponseField>

      <ResponseField name="balance" type="string">
        Current amount available for distribution

        Example: `1234.5`
      </ResponseField>

      <ResponseField name="total_distributed" type="string">
        Total amount distributed in the past

        Example: `100`
      </ResponseField>

      <ResponseField name="updated_at" type="string . date-time">
        Last update timestamp

        Example: `2025-04-16T11:26:31.757Z`
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /partner/api/v1/balance HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/partner/api/v1/balance' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/partner/api/v1/balance', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/partner/api/v1/balance",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Partner balance information theme={null}
{
  "name": "partner-1",
  "api_key": "4VF6LDF7RC64CNGWXOECF8J1LJ62W5HS",
  "valid_since": "2025-05-01T00:00:00.000Z",
  "valid_until": "2025-06-01T00:00:00.000Z",
  "rate": "0.1",
  "balance": "1234.5",
  "total_distributed": "100",
  "updated_at": "2025-04-16T11:26:31.757Z"
}
```

### Distribute Merits

*\* Requires API Key - Add the assigned API KEY in the Authorization header to add your distribution information.*

*Notes:*

* `id` must be unique per each API KEY, so it's recommended to include date or time period describing the distribution period.
* `distributions`
  * Max `1000` wallets per distribution.
  * Amounts less than `0.01` per address are not allowed.
  * Amounts can be in decimals, max 2 decimal digits precision is recommended.
* create\_missing\_accounts
  * `true`: allows distributions to not yet registered Merits accounts.
  * `false`: only allow distributions to users that are already registered.

`POST` `https://merits-staging.blockscout.com/partner/api/v1/distribute`

Distributes merits to specified addresses

**Body**

<ParamField type="string">
  Unique ID for the distribution

  Example: `ethglobal_rewards-2025/05/01`
</ParamField>

<ParamField type="string">
  Human readable description of the distribution

  Example: `Extra rewards from ProjectX for using Blockscout during ETH Global`
</ParamField>

<ParamField type="object[]">
  List of wallet addresses and amounts (max 1000 wallets)

  <Expandable title="properties">
    <ParamField type="string">
      Blockchain address to receive the distribution

      Example: `0x813399e5b08Bb50b038AA7dF6347b6AF2D161338`
    </ParamField>

    <ParamField type="string">
      Amount to distribute

      Example: `10.50`
    </ParamField>
  </Expandable>
</ParamField>

<ParamField type="boolean">
  Allow distribution for non-registered accounts if true

  Example: `false`
</ParamField>

<ParamField type="string">
  Total distribution amount (must equal sum of all amounts)

  Example: `100.00`
</ParamField>

**Responses**

<Accordion title="200 Distribution results">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="accounts_distributed" type="string">
        Number of accounts that received distributions

        Example: `1`
      </ResponseField>

      <ResponseField name="accounts_created" type="string">
        Number of new accounts created during distribution

        Example: `0`
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /partner/api/v1/distribute HTTP/1.1
  Host: merits-staging.blockscout.com
  Content-Type: application/json
  Accept: */*
  Content-Length: 270

  {
    "id": "ethglobal_rewards-2025/05/01",
    "description": "Extra rewards from ProjectX for using Blockscout during ETH Global",
    "distributions": [
      {
        "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
        "amount": "10.50"
      }
    ],
    "create_missing_accounts": false,
    "expected_total": "100.00"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://merits-staging.blockscout.com/partner/api/v1/distribute' \
    --header 'Content-Type: application/json' \
    --data '{
      "id": "ethglobal_rewards-2025/05/01",
      "description": "Extra rewards from ProjectX for using Blockscout during ETH Global",
      "distributions": [
        {
          "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
          "amount": "10.50"
        }
      ],
      "create_missing_accounts": false,
      "expected_total": "100.00"
    }'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/partner/api/v1/distribute', {
      method: 'POST',
      headers: {
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        "id": "ethglobal_rewards-2025/05/01",
        "description": "Extra rewards from ProjectX for using Blockscout during ETH Global",
        "distributions": [
          {
            "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
            "amount": "10.50"
          }
        ],
        "create_missing_accounts": false,
        "expected_total": "100.00"
      })
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.post(
      "https://merits-staging.blockscout.com/partner/api/v1/distribute",
      headers={"Content-Type":"application/json"},
      data=json.dumps({
        "id": "ethglobal_rewards-2025/05/01",
        "description": "Extra rewards from ProjectX for using Blockscout during ETH Global",
        "distributions": [
          {
            "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
            "amount": "10.50"
          }
        ],
        "create_missing_accounts": False,
        "expected_total": "100.00"
      })
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Distribution results theme={null}
{
  "accounts_distributed": "1",
  "accounts_created": "0"
}
```

### Login and Registration Flow - Get User Token

*Use the following flow to get a User Token*

1. Get Nonce from Backend

`GET` `https://merits-staging.blockscout.com/api/v1/auth/nonce`

Returns a nonce for authentication

**Responses**

<Accordion title="200 Authentication nonce">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="nonce" type="string">
        Authentication nonce

        Example: `4MCWIDlddqsmJAAAZ`
      </ResponseField>

      <ResponseField name="merits_login_nonce" type="string | nullable">
        Optional merits-specific login nonce
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v1/auth/nonce HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/api/v1/auth/nonce' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/auth/nonce', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/api/v1/auth/nonce",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Authentication nonce theme={null}
{
  "exists": true,
  "user": {
    "address": "0x813399e5b08Bb50b038AA7dF6347b6AF2D161338",
    "total_balance": "981",
    "referrals": "5",
    "registered_at": "2024-10-21T13:21:20.529Z"
  }
}
```

2. Ask for a signature from a user with a predefined message

```text theme={null}
// Formatted message example


merits.blockscout.com wants you to sign in with your Ethereum account:
0x813399e5b08Bb50b038AA7dF6347b6AF2D163328

Sign-In for the Blockscout Merits program.

URI: 
https://merits-staging.blockscout.com
Version: 1
Chain ID: 1
Nonce: 4MCWIDlddqsmJAZOZ
Issued At: 2025-03-18T12:23:51.549Z
Expiration Time: 2026-03-18T12:23:51.549Z
```

3. Send data to get a user token

`POST` `https://merits-staging.blockscout.com/api/v1/auth/login`

Authenticates a user with a signed message

**Body**

<ParamField type="string">
  Authentication nonce received from the server

  Example: `4MCWIDlddqsmJAAAZ`
</ParamField>

<ParamField type="string">
  The message that was signed

  Example: `merits.blockscout.com wants you to sign in with your Ethereum account: 0x813399e5b08Bb50b038AA7dF6347b6AF2D161338 Sign-In for the Blockscout Merits program. URI: https://merits.blockscout.com Version: 1 Chain ID: 1 Nonce: 4MCWIDlddqsmJAAAZ Issued At: 2025-03-18T12:23:51.549Z Expiration Time: 2026-03-18T12:23:51.549Z`
</ParamField>

<ParamField type="string">
  The signature of the message

  Example: `0xb11b582a6ef196a3f20fa9c84443a92c9f456c9da2ce8ceea2bcf4ce2b936e35767ac2ff56a1de635b7a5f4bcb5da89c4297efb2b4ce559123891202731752661c`
</ParamField>

**Responses**

<Accordion title="200 Authentication result">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="created" type="boolean">
        Indicates if an account was created during this login

        Example: `false`
      </ResponseField>

      <ResponseField name="token" type="string">
        JWT authentication token

        Example: `eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE3NzM4MzY2MzEsImlhdCI6MTc0MjMwMDYzMSwibmJmIjoxNzQyMzAwNjMxLCJzdWIiOiIweDgxMzM5OWU1YjA4QmI1MGIwMzhBQTdkRjYzNDdiNkFGMkQxNsadasdasdasdsajE4MjgiLCJqdGkiOiI0TUNXSURsZGRxc21KQVpPWiIsImNoYWluX2lkIjoxLCJkb21haW4iOiJtZXJpdHMuYmxvY2tzY291dC5jb20ifQ.QQj-dn3ZmHhusq7cvtohF72yxF-605lP7WxVuVZ7BfQ`
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v1/auth/login HTTP/1.1
  Host: merits-staging.blockscout.com
  Content-Type: application/json
  Accept: */*
  Content-Length: 518

  {
    "nonce": "4MCWIDlddqsmJAAAZ",
    "message": "merits.blockscout.com wants you to sign in with your Ethereum account:\n0x813399e5b08Bb50b038AA7dF6347b6AF2D161338\n\nSign-In for the Blockscout Merits program.\n\nURI: https://merits.blockscout.com\nVersion: 1\nChain ID: 1\nNonce: 4MCWIDlddqsmJAAAZ\nIssued At: 2025-03-18T12:23:51.549Z\nExpiration Time: 2026-03-18T12:23:51.549Z",
    "signature": "0xb11b582a6ef196a3f20fa9c84443a92c9f456c9da2ce8ceea2bcf4ce2b936e35767ac2ff56a1de635b7a5f4bcb5da89c4297efb2b4ce559123891202731752661c"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://merits-staging.blockscout.com/api/v1/auth/login' \
    --header 'Content-Type: application/json' \
    --data '{
      "nonce": "4MCWIDlddqsmJAAAZ",
      "message": "merits.blockscout.com wants you to sign in with your Ethereum account:
    0x813399e5b08Bb50b038AA7dF6347b6AF2D161338

    Sign-In for the Blockscout Merits program.

    URI: https://merits.blockscout.com
    Version: 1
    Chain ID: 1
    Nonce: 4MCWIDlddqsmJAAAZ
    Issued At: 2025-03-18T12:23:51.549Z
    Expiration Time: 2026-03-18T12:23:51.549Z",
      "signature": "0xb11b582a6ef196a3f20fa9c84443a92c9f456c9da2ce8ceea2bcf4ce2b936e35767ac2ff56a1de635b7a5f4bcb5da89c4297efb2b4ce559123891202731752661c"
    }'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/auth/login', {
      method: 'POST',
      headers: {
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        "nonce": "4MCWIDlddqsmJAAAZ",
        "message": "merits.blockscout.com wants you to sign in with your Ethereum account:\n0x813399e5b08Bb50b038AA7dF6347b6AF2D161338\n\nSign-In for the Blockscout Merits program.\n\nURI: https://merits.blockscout.com\nVersion: 1\nChain ID: 1\nNonce: 4MCWIDlddqsmJAAAZ\nIssued At: 2025-03-18T12:23:51.549Z\nExpiration Time: 2026-03-18T12:23:51.549Z",
        "signature": "0xb11b582a6ef196a3f20fa9c84443a92c9f456c9da2ce8ceea2bcf4ce2b936e35767ac2ff56a1de635b7a5f4bcb5da89c4297efb2b4ce559123891202731752661c"
      })
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.post(
      "https://merits-staging.blockscout.com/api/v1/auth/login",
      headers={"Content-Type":"application/json"},
      data=json.dumps({
        "nonce": "4MCWIDlddqsmJAAAZ",
        "message": "merits.blockscout.com wants you to sign in with your Ethereum account:\n0x813399e5b08Bb50b038AA7dF6347b6AF2D161338\n\nSign-In for the Blockscout Merits program.\n\nURI: https://merits.blockscout.com\nVersion: 1\nChain ID: 1\nNonce: 4MCWIDlddqsmJAAAZ\nIssued At: 2025-03-18T12:23:51.549Z\nExpiration Time: 2026-03-18T12:23:51.549Z",
        "signature": "0xb11b582a6ef196a3f20fa9c84443a92c9f456c9da2ce8ceea2bcf4ce2b936e35767ac2ff56a1de635b7a5f4bcb5da89c4297efb2b4ce559123891202731752661c"
      })
  )

  data = response.json()
  ```
</CodeGroup>

### API Calls Requiring a User Token

*\*Requires User Token: put the user token in the Authorization header*

`GET` `https://merits-staging.blockscout.com/api/v1/user/balances`

Returns the detailed balance information for the authenticated user

**Responses**

<Accordion title="200 User balance details">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="total" type="string">
        The total balance of the user

        Example: `2426.61`
      </ResponseField>

      <ResponseField name="staked" type="string">
        The amount of tokens staked by the user

        Example: `0`
      </ResponseField>

      <ResponseField name="unstaked" type="string">
        The amount of tokens not staked by the user

        Example: `2426.61`
      </ResponseField>

      <ResponseField name="total_staking_rewards" type="string">
        The total staking rewards earned by the user

        Example: `0`
      </ResponseField>

      <ResponseField name="total_referral_rewards" type="string">
        The total referral rewards earned by the user

        Example: `20`
      </ResponseField>

      <ResponseField name="pending_referral_rewards" type="string">
        The pending referral rewards for the user

        Example: `0`
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v1/user/balances HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/api/v1/user/balances' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/user/balances', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/api/v1/user/balances",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 User balance details theme={null}
{
  "total": "2426.61",
  "staked": "0",
  "unstaked": "2426.61",
  "total_staking_rewards": "0",
  "total_referral_rewards": "20",
  "pending_referral_rewards": "0"
}
```

`GET` `https://merits-staging.blockscout.com/api/v1/user/logs`

Returns activity logs for the authenticated user

**Query parameters**

<ParamField type="integer . int32">
  Number of items to return per page
</ParamField>

<ParamField type="string">
  Token for pagination
</ParamField>

**Responses**

<Accordion title="200 User activity logs">
  <ResponseField name="Response" type="object">
    <Expandable title="properties">
      <ResponseField name="items" type="object[]">
        list of activity logs

        <Expandable title="properties">
          <ResponseField name="action" type="string">
            Type of activity

            Example: `daily_reward`
          </ResponseField>

          <ResponseField name="details" type="object">
            <Expandable title="properties">
              <ResponseField name="streak" type="number . float">
                Streak count for daily rewards

                Example: `1`
              </ResponseField>

              <ResponseField name="amount" type="string">
                Amount of merits received

                Example: 10
              </ResponseField>

              <ResponseField name="date" type="string . date">
                Date of the activity

                Example: 2025-03-18
              </ResponseField>
            </Expandable>
          </ResponseField>

          <ResponseField name="timestamp" type="string . date-time">
            Timestamp of the activity

            Example: `2025-03-18T12:13:20.110Z`
          </ResponseField>
        </Expandable>
      </ResponseField>

      <ResponseField name="next_page_params" type="object">
        <Expandable title="properties">
          <ResponseField type="string">
            Token for the next page

            Example: `1732067538792818,984727`
          </ResponseField>

          <ResponseField type="integer . int32">
            Size of the page

            Example: `50`
          </ResponseField>
        </Expandable>
      </ResponseField>
    </Expandable>
  </ResponseField>
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v1/user/logs HTTP/1.1
  Host: merits-staging.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://merits-staging.blockscout.com/api/v1/user/logs' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://merits-staging.blockscout.com/api/v1/user/logs', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://merits-staging.blockscout.com/api/v1/user/logs",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>


# MCP Server
Source: https://docs.blockscout.com/devs/mcp-server

Wraps Blockscout APIs to expose blockchain data such as balances, tokens, NFTs, and contract metadata via MCP

<Tip>
  * MCP Landing page: [https://mcp.blockscout.com](https://mcp.blockscout.com)
  * Github with technical specs and run information located at [https://github.com/blockscout/mcp-server](https://github.com/blockscout/mcp-server)
</Tip>

The Model Context Protocol (MCP) is an open protocol designed to allow AI agents, IDEs, and automation tools to consume, query, and analyze structured data through context-aware APIs.

This server wraps Blockscout APIs and exposes blockchain data—balances, tokens, NFTs, contract metadata—via MCP so that AI agents and tools (like Claude, Cursor, or IDEs) can access and analyze it contextually.

#### **Key Features:**

* Contextual blockchain data access for AI tools
* Multi-chain support via getting Blockscout instance URLs from Chainscout
* Custom instructions for MCP host to use the server
* Supports MCP progress notifications for multi-step tool operations, allowing clients to track execution status
* Enhanced User Experience: Provides periodic progress updates for long-running API queries (e.g., fetching extensive transaction histories) when requested by the client, improving responsiveness

#### Use Cases

* Enabling AI agents to analyze blockchain transactions and account balances.
* Automating blockchain data analysis workflows with context-aware APIs.
* Allowing IDEs to fetch contract ABIs and other relevant smart contract information.

### Examples

* Using the MCP to [find ENV variables for rollup deployments](/devs/mcp-examples/rollup-deployment-variables).

#### **Architecture and Data Flow**

```mermaid theme={null}
sequenceDiagram
    participant AI as MCP Host
    participant MCP as MCP Server
    participant BENS as ENS Service
    participant CS as Chainscout
    participant BS as Blockscout Instance
    participant Metadata as Metadata Service

    AI->>MCP: __get_instructions__
    MCP-->>AI: Custom instructions

    AI->>MCP: get_address_by_ens_name
    MCP->>BENS: Forward ENS name resolution request
    BENS-->>MCP: Address response
    MCP-->>AI: Formatted address

    AI->>MCP: get_chains_list
    MCP->>CS: Request available chains
    CS-->>MCP: List of chains
    MCP-->>AI: Formatted chains list

    Note over AI: Host selects chain_id as per the user's initial prompt

    AI->>MCP: Tool request with chain_id
    MCP->>CS: GET /api/chains/:id
    CS-->>MCP: Chain metadata (includes Blockscout URL)
    par Concurrent API Calls (when applicable)
        MCP->>BS: Request to Blockscout API
        BS-->>MCP: Primary data response
    and
        MCP->>Metadata: Request to Metadata API (for enriched data)
        Metadata-->>MCP: Secondary data response
    end
    MCP-->>AI: Formatted & combined information
```


# PRO API
Source: https://docs.blockscout.com/devs/pro-api

Blockscout's PRO API provides higher call limits and custom endpoints

<Tip>
  Blockscout PRO API is currently in development. If you are interested in beta testing our API, [reach out in Discord](https://discord.gg/blockscout).
</Tip>

## General Info

The PRO API  expands on Blockscout's free tier API (5 requests per second) to provide expanded rate limits for high-usage projects on Blockscout hosted networks. Pricing and details are coming soon.

## Authorization

You can pass api key using either:

* `apikey` query parameter
* `authorization` header

## PRO API routes (in progress)

1. **API v1**
   1. base\_url/v2/api?chain\_id=:chain\_id

      `https://api.k8s-dev.blockscout.com/v2/api?chain_id=17000&module=block&action=eth_block_number&apikey=proapi_xxxxxxxx`
   2. base\_url/:chain\_id/api

      `https://api.k8s-dev.blockscout.com/17000/api?module=block&action=eth_block_number&apikey=proapi_xxxxxxxx`
2. **API v2**

   base\_url/:chain\_id/api/v2

   `https://api.k8s-dev.blockscout.com/17000/api/v2/blocks?apikey=proapi_xxxxxxxx`
3. **ETH RPC API**

   base\_url/:chain\_id/json-rpc `https://api.k8s-dev.blockscout.com/17000/json-rpc?apikey=proapi_xxxxxxxx`


# Link To Blockscout
Source: https://docs.blockscout.com/devs/replace-links

Easily replace your current explorer links with Blockscout explorer links

## Replace the primary explorer link

In most cases simply replacing the first part of the url is all that is needed to replace Etherscan with Blockscout.

For example, replace [https://etherscan.io/](https://etherscan.io/) with [https://eth.blockscout.com/](https://eth.blockscout.com/) in your code and the corresponding links to blocks, transactions, etc will be mapped to Blockscout rather than Etherscan.

<Check>
  😢 Tx before replacement

  [https://etherscan.io/tx/0x3e8c3aad50b2f8471400e3fe6b812f20c332846064dff8c25fadf783eefa68df](https://etherscan.io/tx/0x3e8c3aad50b2f8471400e3fe6b812f20c332846064dff8c25fadf783eefa68df)

  😁 Tx after replacement

  [https://eth.blockscout.com/tx/0x3e8c3aad50b2f8471400e3fe6b812f20c332846064dff8c25fadf783eefa68df](https://eth.blockscout.com/tx/0x3e8c3aad50b2f8471400e3fe6b812f20c332846064dff8c25fadf783eefa68df)
</Check>

Blockscout linking architecture follows [EIP-3091](https://eips.ethereum.org/EIPS/eip-3091)standardization for the following routes:

* Blocks `<BLOCK_EXPLORER_URL>/block/<BLOCK_HASH_OR_HEIGHT>`
* Transactions `<BLOCK_EXPLORER_URL>/tx/<TX_HASH>`
* Accounts `<BLOCK_EXPLORER_URL>/address/<ACCOUNT_ADDRESS>`
* Tokens `<BLOCK_EXPLORER_URL>/token/<TOKEN_ADDRESS>`

### UTM tags

We encourage adding UTM tags with your project information to Blockscout links. This helps us track referrals and improve our overall performance via metrics. Simply append `?utm_source=<your_project_name>` to the end of any links pointing to Blockscout. For example [https://eth.blockscout.com/?utm\_source=tenderly](https://eth.blockscout.com/?utm_source=Tenderly)

### Common chain replacements

Replace the Etherscan url in your code with the Blockscout url for a seamless transition. All chains supported by Etherscan are also supported by Blockscout (along with many additional Blockscout chains). Some examples are below. For additional Blockscout chains see the [chains and projects](https://www.blockscout.com/chains-and-projects) page or the [chainscout json file which includes chainids](https://github.com/blockscout/chainscout/blob/main/data/chains.json).

| Chain            | Etherscan ❌                                                                      | Blockscout ✅                                                                         |
| ---------------- | -------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------ |
| Ethereum         | [https://etherscan.io/](https://etherscan.io/)                                   | [https://eth.blockscout.com/](https://eth.blockscout.com/)                           |
| Ethereum Sepolia | [https://sepolia.etherscan.io/](https://sepolia.etherscan.io/)                   | [https://eth-sepolia.blockscout.com/](https://eth-sepolia.blockscout.com/)           |
| Optimism         | [https://optimistic.etherscan.io/](https://optimistic.etherscan.io/)             | [https://optimism.blockscout.com/](https://optimism.blockscout.com/)                 |
| Optimism Sepolia | [https://sepolia-optimism.etherscan.io/](https://sepolia-optimism.etherscan.io/) | [https://optimism-sepolia.blockscout.com/](https://optimism-sepolia.blockscout.com/) |
| Base             | [https://basescan.org/](https://basescan.org/)                                   | [https://base.blockscout.com/](https://base.blockscout.com/)                         |
| Base Sepolia     | [https://sepolia.basescan.org/](https://sepolia.basescan.org/)                   | [https://base-sepolia.blockscout.com/](https://base-sepolia.blockscout.com/)         |
| Arbitrum         | [https://arbiscan.io/](https://arbiscan.io/)                                     | [https://arbitrum.blockscout.com/](https://arbitrum.blockscout.com/)                 |
| Arbitrum Sepolia | [https://sepolia.arbiscan.io/](https://sepolia.arbiscan.io/)                     | [https://arbitrum-sepolia.blockscout.com/](https://arbitrum-sepolia.blockscout.com/) |
| Polygon          | [https://polygonscan.com/](https://polygonscan.com/)                             | [https://polygon.blockscout.com/](https://polygon.blockscout.com/)                   |
| Gnosis           | [https://gnosisscan.io/](https://gnosisscan.io/)                                 | [https://gnosis.blockscout.com/](https://gnosis.blockscout.com/)                     |
| Celo             | [https://celoscan.io/](https://celoscan.io/)                                     | [https://celo.blockscout.com/](https://celo.blockscout.com/)                         |
| Unichain         | [https://uniscan.xyz/](https://uniscan.xyz/)                                     | [https://unichain.blockscout.com/](https://unichain.blockscout.com/)                 |

### Exceptions

Some newer operations without standards are still handled differently by different explorers. For example:

* Blobs on Blockscout are accessed in different ways depending on the route. For example via the `?tab=blob_txs` query string following a block ([https://eth.blockscout.com/block/20822532?tab=blob\_txs](https://eth.blockscout.com/block/20822532?tab=blob_txs)) or the `?tab=blobs` query string following a transaction. Blobs on Etherscan are accessed via `#blobinfo` query string following a block (ie [https://etherscan.io/block/20822532#blobinfo](https://etherscan.io/block/20822532#blobinfo)).
* User Operations (EIP-4337) are displayed on Blockscout via the [https://eth.blockscout.com/ops](https://eth.blockscout.com/ops) url. On Etherscan there is currently no defined route, but User Operations can be viewed with the `Handle Ops` filter applied to the senders address (ie [https://etherscan.io/advanced-filter?fadd=0x20e9695f25413f14e5807b530D0698bd4F155074\&mtd=0x1fad948c\~Handle+Ops\&ps=10\&p=8](https://etherscan.io/advanced-filter?fadd=0x20e9695f25413f14e5807b530D0698bd4F155074\&mtd=0x1fad948c~Handle+Ops\&ps=10\&p=8))

## Replace the API link

<Info>
  Standard Blockscout RPC calls do not need an API key (Etherscan calls always require one). You can remove the `&apikey=YourApiKeyToken` query string at the end of the url with no problem or keep it as any string value and Blockscout will process. If you want to increase your limits, you can also [sign up for a free Blockscout API key](/using-blockscout/my-account/api-keys) and use it to access 10 RPS limits.
</Info>

Etherscan uses a subdomain link for api access. For example, the Ethereum explorer the api link is [https://api.etherscan.io/](https://api.etherscan.io/) followed by your query, or for Optimism it is [https://api-optimistic.etherscan.io/](https://api-optimistic.etherscan.io/) followed by your query.

**To replace, simply use the regular blockscout url for the instance**, for example [https://eth.blockscout.com/](https://eth.blockscout.com/) for Ethereum or [https://optimism.blockscout.com/](https://optimism.blockscout.com/) for Optimism.

<Check>
  😢 API call before replacement (doesn't work without API key)

  [https://api.etherscan.io/api?module=account\&action=balance\&address=0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae\&tag=latest\&apikey=YourApiKeyToken](https://api.etherscan.io/api?module=account\&action=balance\&address=0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae\&tag=latest\&apikey=YourApiKeyToken)

  😁 API call after replacement (works without API key)

  [https://eth.blockscout.com/api?module=account\&action=balance\&address=0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae\&tag=latest](https://eth.blockscout.com/api?module=account\&action=balance\&address=0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae\&tag=latest)
</Check>

Standard API routes on Etherscan work for your queries on Blockscout. We've structured our data calls to be consistent with Etherscan whenever possible. You can see supported calls in the [JSON RPC & ETH Compatible RPC endpoints section](/devs/apis/rpc).

<Check>
  If you require more varied or richer datasets consider replacing your JSON RPC calls with the [REST API from Blockscout](/devs/apis/rest). This free API features additional metadata, stats data, human readable transactions and more.
</Check>

### API Exceptions

* Blockscout does not currently support most [Etherscan API PRO](https://docs.etherscan.io/api-pro/etherscan-api-pro) queries.
* The 10 RPS limits can be increased further via the [Quicknode marketplace add-on](https://marketplace.quicknode.com/add-on/blockscout-json-rpc-api).

## Replace your wallet block explorer link

Every wallet handles the explorer link differently, but typically wallets ship with Etherscan links by default. To change, simply go to settings and replace the Etherscan link with the Blockscout one. Here's how you do it in MetaMask.

1. Open MetaMask, click the dots to open the menu, and select Settings
2. Select Networks
3. Select the network where you want to change the explorer link

<Frame>
  <img alt="" />
</Frame>

4. Find the block explorer url (ie [https://optimistic.etherscan.io/](https://optimistic.etherscan.io/)).
5. Change the url to blockscout (ie [https://optimism.blockscout.com/](https://optimism.blockscout.com/)) and Save.

<Frame>
  <img alt="" />
</Frame>

<Check>
  Repeat this process for all networks from the Networks screen.
</Check>


# Smart Contract Verification
Source: https://docs.blockscout.com/devs/verification

Verifying your deployed contract using contract source code, JSON input, Sourcify and more.

Once verified, a smart contract or token contract's source code becomes publicly available and verifiable, creating transparency and trust. It also allows for interactivity with methods directly through the Read and Write buttons.

There are many different ways to verify your contracts with Blockscout.

* [Blockscout UI](/devs/verification/blockscout-ui)
* [Verification API](/devs/verification/blockscout-smart-contract-verification-api)
* [Hardhat Plugin](/devs/verification/hardhat-verification-plugin)
* [Foundry Verification](/devs/verification/foundry-verification)
* [Sourcify Verification](/devs/verification/contracts-verification-via-sourcify)
* [Remix Verification](/devs/verification/remix-verification)
* [Automate verification with Catapulta](/devs/verification/automate-verifications-catapulta)
* [Stylus verification via API](/devs/verification/stylus-verification)
* [Thirdweb verification](/devs/verification/verification-via-thirdweb)


# Automate verifications with Catapulta
Source: https://docs.blockscout.com/devs/verification/automate-verifications-catapulta

Deploy smart contracts and get verified automatically with Catapulta

[Catapulta](https://catapulta.sh) is a multi-chain smart contracts deployment tool for Foundry and Hardhat to improve deployments DevX and remove the need to perform manual verifications.

With Catapulta you can deploy to +14 networks and the verification will happen automatically in Blockscout based block explorers. You may need to register in Catapulta to be able to deploy in testnets with automatic verification, for free, in Blockscout based explorers.

You can install `catapulta` in your Linux/MacOs machine using NPM:

```sh theme={null}
npm i -g catapulta
```

## Deploy with Foundry and Catapulta

To verify at deployment time with Foundry and Catapulta, just broadcast your script with the Catapulta CLI:

```sh theme={null}
catapulta script scripts/Deploy.s.sol --network [NETWORK_NAME]
```

If you already deployed with Forge, but want to automate the verification, you can import your deployment to Catapulta with the "catapulta import" command, and it will re-trigger verification:

```sh theme={null}
catapulta import 'broadcasts/Deploy.s.sol/[chain id]/run-latest.json'
```

## Deploy with Hardhat and Catapulta

To verify at deployment time with `hardhat-deploy` and Catapulta, just deploy with Catapulta CLI to enjoy automated verifications.

```sh theme={null}
catapulta deploy --network [NETWORK_NAME]
```

If you use plain Hardhat scripts, you can use `catapulta run`, pointing to your Javascript or Typescript deploy script:

```sh theme={null}
catapulta run scripts/DeployScript.ts --network [NETWORK_NAME]
```

## Verify your project anytime, with one button

In case Blockscout is newly added to a network you already deployed with Catapulta, you can always re-trigger verification to your entire project with only one click, from your deployment report, and Catapulta will take care to migrate all the verifications to Blockscout block explorer.

<Frame>
  <img />
</Frame>


# Blockscout Smart Contract Verification API
Source: https://docs.blockscout.com/devs/verification/blockscout-smart-contract-verification-api

Blockscout also offers a contract verification API.

This is the preferred option for contract verification via API. However, you can also use RPC endpoints, [more info is available here](/devs/apis/rpc/contract#verify-a-contract-with-its-source-code-and-contract-creation-information).

### License type

You can specify license type of the smart contract as `string` or `number`. For example for `GNU General Public License v2.0 (GNU GPLv2)` you could pass either `4` or `"gnu_gpl_v2"`

We are supporting such types of license as:

```java theme={null}
1. No License (None)
2. The Unlicense (Unlicense)
3. MIT License (MIT)
4. GNU General Public License v2.0 (GNU GPLv2)
5. GNU General Public License v3.0 (GNU GPLv3)
6. GNU Lesser General Public License v2.1 (GNU LGPLv2.1)
7. GNU Lesser General Public License v3.0 (GNU LGPLv3)
8. BSD 2-clause "Simplified" license (BSD-2-Clause)
9. BSD 3-clause "New" Or "Revised" license* (BSD-3-Clause)
10. Mozilla Public License 2.0 (MPL-2.0)
11. Open Software License 3.0 (OSL-3.0)
12. Apache 2.0 (Apache-2.0)
13. GNU Affero General Public License (GNU AGPLv3)
14. Business Source License (BSL 1.1)
```

API license types:

```
none
unlicense
mit
gnu_gpl_v2
gnu_gpl_v3
gnu_lgpl_v2_1
gnu_lgpl_v3
bsd_2_clause
bsd_3_clause
mpl_2_0
osl_3_0
apache_2_0
gnu_agpl_v3
bsl_1_1
```

### Verify smart contract

Use the appropriate Blockscout instance endpoint to verify if the smart contract microservice is enabled.

In the following examples we use [https://eth.blockscout.com](https://eth.blockscout.com) to query Ethereum.

### verification service running

`GET` `https://eth.blockscout.com/api/v2/smart-contracts/verification/config`

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  GET /api/v2/smart-contracts/verification/config HTTP/1.1
  Host: eth.blockscout.com
  Accept: */*
  ```

  ```sh cURL theme={null}
  curl -L \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/verification/config' \
    --header 'Accept: */*'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/verification/config', {
      method: 'GET',
      headers: {
        "Accept": "*/*"
      },
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.get(
      "https://eth.blockscout.com/api/v2/smart-contracts/verification/config",
      headers={"Accept":"*/*"},
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

<Warning>
  `0x` contract addresses in POST example urls below should be replaced with your contract hash supplied on contract creation. Variables in the body are examples and should be replaced with your contract details.
</Warning>

## Flattened contract

For more information on parameters to pass, see the [flattened source code information on the Verifying a smart contract page](/devs/verification#via-flattened-source-code).

### verification flattened contract

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0xb12cad649a56e67188bbaa56583c18dc7d2812ed/verification/via/flattened-code`

**Body**

<ParamField>
  Example: `{"compiler_version":"v0.8.17+commit.8df45f5f","license_type":"mit","source_code":"// SPDX-License-Identifier: GPL-3.0\n\npragma solidity >=0.7.0 <0.9.0;\n\n/**\n * @title Owner\n * @dev Set & change owner\n */\ncontract Owner {\n\n address private owner;\n \n // event for EVM logging 2345678ewqwertyui54567890987654345678\n event OwnerSet(address indexed oldOwner, address indexed newOwner);\n \n // modifier to check if caller is owner\n modifier isOwner() {\n // If the first argument of 'require' evaluates to 'false', execution terminates and all\n // changes to the state and to Ether balances are reverted.\n // This used to consume all gas in old EVM versions, but not anymore.\n // It is often a good idea to use 'require' to check if functions are called correctly.\n // As a second argument, you can also provide an explanation about what went wrong.\n require(msg.sender == owner, \"Caller is not owner\");\n _;\n }\n \n /**\n * @dev Set contract deployer as owner\n */\n constructor(uint112 abc, address abb, bytes32 ghnc) {\n // console.log(\"Owner contract deployed by:\", msg.sender);\n owner = msg.sender; // 'msg.sender' is sender of current call, contract deployer for a constructor\n emit OwnerSet(address(0), owner);\n }\n\n /**\n * @dev Change owner\n * @param newOwner address of new owner\n */\n function changeOwner(address newOwner) public isOwner {\n emit OwnerSet(owner, newOwner);\n owner = newOwner;\n }\n\n /**\n * @dev Return owner address \n * @return address of owner\n */\n function getOwner() external view returns (address) {\n return owner;\n }\n}","is_optimization_enabled":true,"optimization_runs":199,"contract_name":"Owner","libraries":{"Libcheck":"0x030f7c7dbd472864220bcf9e37ede1b8a3125970","Libcheck_1":"0x030f7c7dbd472864220bcf9e37ede1b8a3125970"},"evm_version":"berlin","autodetect_constructor_args":true}`
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0xb12cad649a56e67188bbaa56583c18dc7d2812ed/verification/via/flattened-code HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: application/json
  Accept: */*
  Content-Length: 2029

  {
    "compiler_version": "v0.8.17+commit.8df45f5f",
    "license_type": "mit",
    "source_code": "// SPDX-License-Identifier: GPL-3.0\n\npragma solidity >=0.7.0 <0.9.0;\n\n/**\n * @title Owner\n * @dev Set & change owner\n */\ncontract Owner {\n\n    address private owner;\n    \n    // event for EVM logging 2345678ewqwertyui54567890987654345678\n    event OwnerSet(address indexed oldOwner, address indexed newOwner);\n    \n    // modifier to check if caller is owner\n    modifier isOwner() {\n        // If the first argument of 'require' evaluates to 'false', execution terminates and all\n        // changes to the state and to Ether balances are reverted.\n        // This used to consume all gas in old EVM versions, but not anymore.\n        // It is often a good idea to use 'require' to check if functions are called correctly.\n        // As a second argument, you can also provide an explanation about what went wrong.\n        require(msg.sender == owner, \"Caller is not owner\");\n        _;\n    }\n    \n    /**\n     * @dev Set contract deployer as owner\n     */\n    constructor(uint112 abc, address abb, bytes32 ghnc) {\n        // console.log(\"Owner contract deployed by:\", msg.sender);\n        owner = msg.sender; // 'msg.sender' is sender of current call, contract deployer for a constructor\n        emit OwnerSet(address(0), owner);\n    }\n\n    /**\n     * @dev Change owner\n     * @param newOwner address of new owner\n     */\n    function changeOwner(address newOwner) public isOwner {\n        emit OwnerSet(owner, newOwner);\n        owner = newOwner;\n    }\n\n    /**\n     * @dev Return owner address \n     * @return address of owner\n     */\n    function getOwner() external view returns (address) {\n        return owner;\n    }\n}",
    "is_optimization_enabled": true,
    "optimization_runs": 199,
    "contract_name": "Owner",
    "libraries": {
      "Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970",
      "Libcheck_1": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"
    },
    "evm_version": "berlin",
    "autodetect_constructor_args": true
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0xb12cad649a56e67188bbaa56583c18dc7d2812ed/verification/via/flattened-code' \
    --header 'Content-Type: application/json' \
    --data '{
      "compiler_version": "v0.8.17+commit.8df45f5f",
      "license_type": "mit",
      "source_code": "// SPDX-License-Identifier: GPL-3.0

    pragma solidity >=0.7.0 <0.9.0;

    /**
     * @title Owner
     * @dev Set & change owner
     */
    contract Owner {

        address private owner;
        
        // event for EVM logging 2345678ewqwertyui54567890987654345678
        event OwnerSet(address indexed oldOwner, address indexed newOwner);
        
        // modifier to check if caller is owner
        modifier isOwner() {
            // If the first argument of 'require' evaluates to 'false', execution terminates and all
            // changes to the state and to Ether balances are reverted.
            // This used to consume all gas in old EVM versions, but not anymore.
            // It is often a good idea to use 'require' to check if functions are called correctly.
            // As a second argument, you can also provide an explanation about what went wrong.
            require(msg.sender == owner, \"Caller is not owner\");
            _;
        }
        
        /**
         * @dev Set contract deployer as owner
         */
        constructor(uint112 abc, address abb, bytes32 ghnc) {
            // console.log(\"Owner contract deployed by:\", msg.sender);
            owner = msg.sender; // 'msg.sender' is sender of current call, contract deployer for a constructor
            emit OwnerSet(address(0), owner);
        }

        /**
         * @dev Change owner
         * @param newOwner address of new owner
         */
        function changeOwner(address newOwner) public isOwner {
            emit OwnerSet(owner, newOwner);
            owner = newOwner;
        }

        /**
         * @dev Return owner address 
         * @return address of owner
         */
        function getOwner() external view returns (address) {
            return owner;
        }
    }",
      "is_optimization_enabled": true,
      "optimization_runs": 199,
      "contract_name": "Owner",
      "libraries": {
        "Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970",
        "Libcheck_1": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"
      },
      "evm_version": "berlin",
      "autodetect_constructor_args": true
    }'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0xb12cad649a56e67188bbaa56583c18dc7d2812ed/verification/via/flattened-code', {
      method: 'POST',
      headers: {
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        "compiler_version": "v0.8.17+commit.8df45f5f",
        "license_type": "mit",
        "source_code": "// SPDX-License-Identifier: GPL-3.0\n\npragma solidity >=0.7.0 <0.9.0;\n\n/**\n * @title Owner\n * @dev Set & change owner\n */\ncontract Owner {\n\n    address private owner;\n    \n    // event for EVM logging 2345678ewqwertyui54567890987654345678\n    event OwnerSet(address indexed oldOwner, address indexed newOwner);\n    \n    // modifier to check if caller is owner\n    modifier isOwner() {\n        // If the first argument of 'require' evaluates to 'false', execution terminates and all\n        // changes to the state and to Ether balances are reverted.\n        // This used to consume all gas in old EVM versions, but not anymore.\n        // It is often a good idea to use 'require' to check if functions are called correctly.\n        // As a second argument, you can also provide an explanation about what went wrong.\n        require(msg.sender == owner, \"Caller is not owner\");\n        _;\n    }\n    \n    /**\n     * @dev Set contract deployer as owner\n     */\n    constructor(uint112 abc, address abb, bytes32 ghnc) {\n        // console.log(\"Owner contract deployed by:\", msg.sender);\n        owner = msg.sender; // 'msg.sender' is sender of current call, contract deployer for a constructor\n        emit OwnerSet(address(0), owner);\n    }\n\n    /**\n     * @dev Change owner\n     * @param newOwner address of new owner\n     */\n    function changeOwner(address newOwner) public isOwner {\n        emit OwnerSet(owner, newOwner);\n        owner = newOwner;\n    }\n\n    /**\n     * @dev Return owner address \n     * @return address of owner\n     */\n    function getOwner() external view returns (address) {\n        return owner;\n    }\n}",
        "is_optimization_enabled": true,
        "optimization_runs": 199,
        "contract_name": "Owner",
        "libraries": {
          "Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970",
          "Libcheck_1": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"
        },
        "evm_version": "berlin",
        "autodetect_constructor_args": true
      })
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0xb12cad649a56e67188bbaa56583c18dc7d2812ed/verification/via/flattened-code",
      headers={"Content-Type":"application/json"},
      data=json.dumps({
        "compiler_version": "v0.8.17+commit.8df45f5f",
        "license_type": "mit",
        "source_code": "// SPDX-License-Identifier: GPL-3.0\n\npragma solidity >=0.7.0 <0.9.0;\n\n/**\n * @title Owner\n * @dev Set & change owner\n */\ncontract Owner {\n\n    address private owner;\n    \n    // event for EVM logging 2345678ewqwertyui54567890987654345678\n    event OwnerSet(address indexed oldOwner, address indexed newOwner);\n    \n    // modifier to check if caller is owner\n    modifier isOwner() {\n        // If the first argument of 'require' evaluates to 'false', execution terminates and all\n        // changes to the state and to Ether balances are reverted.\n        // This used to consume all gas in old EVM versions, but not anymore.\n        // It is often a good idea to use 'require' to check if functions are called correctly.\n        // As a second argument, you can also provide an explanation about what went wrong.\n        require(msg.sender == owner, \"Caller is not owner\");\n        _;\n    }\n    \n    /**\n     * @dev Set contract deployer as owner\n     */\n    constructor(uint112 abc, address abb, bytes32 ghnc) {\n        // console.log(\"Owner contract deployed by:\", msg.sender);\n        owner = msg.sender; // 'msg.sender' is sender of current call, contract deployer for a constructor\n        emit OwnerSet(address(0), owner);\n    }\n\n    /**\n     * @dev Change owner\n     * @param newOwner address of new owner\n     */\n    function changeOwner(address newOwner) public isOwner {\n        emit OwnerSet(owner, newOwner);\n        owner = newOwner;\n    }\n\n    /**\n     * @dev Return owner address \n     * @return address of owner\n     */\n    function getOwner() external view returns (address) {\n        return owner;\n    }\n}",
        "is_optimization_enabled": True,
        "optimization_runs": 199,
        "contract_name": "Owner",
        "libraries": {
          "Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970",
          "Libcheck_1": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"
        },
        "evm_version": "berlin",
        "autodetect_constructor_args": True
      })
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Via Standard JSON input

For more information on parameters to pass, see the [flattened source code information on the Verifying a smart contract page](/devs/verification#via-flattened-source-code). `0x` contract in POST example should be replaced with your contract hash.

### verification standard json

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0x9c1c619176b4f8521a0ab166945d785b92aef453/verification/via/standard-input`

**Body**

<ParamField type="number">
  Example: `v0.8.17+commit.8df45f5f`
</ParamField>

<ParamField type="string">
  Example: `Owner`
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="boolean">
  Example: `false`
</ParamField>

<ParamField type="string">
  Example: `00000000000000000000000000000000000000000000000000000002d2982db3000000000000000000000000bb36c792b9b45aaf8b848a1392b0d6559202729e666f6f0000000000000000000000000000000000000000000000000000000000`
</ParamField>

<ParamField type="string">
  Example: `gnu_gpl_v2`
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0x9c1c619176b4f8521a0ab166945d785b92aef453/verification/via/standard-input HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: multipart/form-data
  Accept: */*
  Content-Length: 370

  {
    "compiler_version": "v0.8.17+commit.8df45f5f",
    "contract_name": "Owner",
    "files[0]": "binary",
    "autodetect_constructor_args": "false",
    "constructor_args": "00000000000000000000000000000000000000000000000000000002d2982db3000000000000000000000000bb36c792b9b45aaf8b848a1392b0d6559202729e666f6f0000000000000000000000000000000000000000000000000000000000",
    "license_type": "gnu_gpl_v2"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0x9c1c619176b4f8521a0ab166945d785b92aef453/verification/via/standard-input' \
    --header 'Content-Type: multipart/form-data' \
    --form 'compiler_version=v0.8.17+commit.8df45f5f' \
    --form 'contract_name=Owner' \
    --form 'files[0]=binary' \
    --form 'autodetect_constructor_args=false' \
    --form 'constructor_args=00000000000000000000000000000000000000000000000000000002d2982db3000000000000000000000000bb36c792b9b45aaf8b848a1392b0d6559202729e666f6f0000000000000000000000000000000000000000000000000000000000' \
    --form 'license_type=gnu_gpl_v2'
  ```

  ```js JavaScript theme={null}
  const formData = new FormData();

  formData.append("compiler_version", "v0.8.17+commit.8df45f5f");
  formData.append("contract_name", "Owner");
  formData.append("files[0]", "binary");
  formData.append("autodetect_constructor_args", "false");
  formData.append("constructor_args", "00000000000000000000000000000000000000000000000000000002d2982db3000000000000000000000000bb36c792b9b45aaf8b848a1392b0d6559202729e666f6f0000000000000000000000000000000000000000000000000000000000");
  formData.append("license_type", "gnu_gpl_v2");

  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0x9c1c619176b4f8521a0ab166945d785b92aef453/verification/via/standard-input', {
      method: 'POST',
      headers: {
        "Content-Type": "multipart/form-data"
      },
      body: formData
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  files = {
      "compiler_version": "v0.8.17+commit.8df45f5f",
      "contract_name": "Owner",
      "files[0]": "binary",
      "autodetect_constructor_args": "false",
      "constructor_args": "00000000000000000000000000000000000000000000000000000002d2982db3000000000000000000000000bb36c792b9b45aaf8b848a1392b0d6559202729e666f6f0000000000000000000000000000000000000000000000000000000000",
      "license_type": "gnu_gpl_v2",
  }

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0x9c1c619176b4f8521a0ab166945d785b92aef453/verification/via/standard-input",
      headers={"Content-Type":"multipart/form-data"},
      files=files
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Via Sourcify Files

For more information on parameters to pass, see the [Contract Verification via Sourcify](/devs/verification/contracts-verification-via-sourcify). `0x` contract in POST example url should be replaced with your contract hash, as should your relevant variables.

### verification sourcify

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/sourcify`

**Body**

<ParamField type="string">
   
</ParamField>

<ParamField type="integer">
  Example: `4`
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/sourcify HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: multipart/form-data
  Accept: */*
  Content-Length: 47

  {
    "files[0]": "text",
    "chosen_contract_index": "4"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/sourcify' \
    --header 'Content-Type: multipart/form-data' \
    --form 'files[0]=text' \
    --form 'chosen_contract_index=4'
  ```

  ```js JavaScript theme={null}
  const formData = new FormData();

  formData.append("files[0]", "text");
  formData.append("chosen_contract_index", "4");

  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/sourcify', {
      method: 'POST',
      headers: {
        "Content-Type": "multipart/form-data"
      },
      body: formData
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  files = {
      "files[0]": "text",
      "chosen_contract_index": "4",
  }

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/sourcify",
      headers={"Content-Type":"multipart/form-data"},
      files=files
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Multi-part Solidity files

### verification multipart Copy

`POST` `https\://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/multi-part`

**Body**

<ParamField type="number">
  Example: `v0.8.17+commit.8df45f5f`
</ParamField>

<ParamField type="string">
  Example: `gnu_gpl_v3`
</ParamField>

<ParamField type="boolean">
  Example: `true`
</ParamField>

<ParamField type="string">
  Example: `{"Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"}`
</ParamField>

<ParamField type="string">
  Example: `london`
</ParamField>

<ParamField type="integer">
  Example: `199`
</ParamField>

<ParamField type="string">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/multi-part HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: multipart/form-data
  Accept: */*
  Content-Length: 271

  {
    "compiler_version": "v0.8.17+commit.8df45f5f",
    "license_type": "gnu_gpl_v3",
    "is_optimization_enabled": "true",
    "libraries": "{\"Libcheck\": \"0x030f7c7dbd472864220bcf9e37ede1b8a3125970\"}",
    "evm_version": "london",
    "optimization_runs": "199",
    "files[0]": "text",
    "files[1]": "binary"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/multi-part' \
    --header 'Content-Type: multipart/form-data' \
    --form 'compiler_version=v0.8.17+commit.8df45f5f' \
    --form 'license_type=gnu_gpl_v3' \
    --form 'is_optimization_enabled=true' \
    --form 'libraries={"Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"}' \
    --form 'evm_version=london' \
    --form 'optimization_runs=199' \
    --form 'files[0]=text' \
    --form 'files[1]=binary'
  ```

  ```js JavaScript theme={null}
  const formData = new FormData();

  formData.append("compiler_version", "v0.8.17+commit.8df45f5f");
  formData.append("license_type", "gnu_gpl_v3");
  formData.append("is_optimization_enabled", "true");
  formData.append("libraries", "{"Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"}");
  formData.append("evm_version", "london");
  formData.append("optimization_runs", "199");
  formData.append("files[0]", "text");
  formData.append("files[1]", "binary");

  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/multi-part', {
      method: 'POST',
      headers: {
        "Content-Type": "multipart/form-data"
      },
      body: formData
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  files = {
      "compiler_version": "v0.8.17+commit.8df45f5f",
      "license_type": "gnu_gpl_v3",
      "is_optimization_enabled": "true",
      "libraries": "{"Libcheck": "0x030f7c7dbd472864220bcf9e37ede1b8a3125970"}",
      "evm_version": "london",
      "optimization_runs": "199",
      "files[0]": "text",
      "files[1]": "binary",
  }

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0x030f7c7dbd472864220bcf9e37ede1b8a3125970/verification/via/multi-part",
      headers={"Content-Type":"multipart/form-data"},
      files=files
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Vyper Contracts

### verification vyper contract

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0xd73249995040f04cb891bdf0f997579ee3a6676c/verification/via/vyper-code`

**Body**

<ParamField>
  Example: `{"compiler_version":"v0.2.12+commit.2c6842c","license_type":"gnu_agpl_v3","source_code":"from vyper.interfaces import ERC20\n\nimplements: ERC20\n\nevent Transfer:\n    sender: indexed(address)\n    receiver: indexed(address)\n    value: uint256\n\nevent Approval:\n    owner: indexed(address)\n    spender: indexed(address)\n    value: uint256\n\nname: public(String[64])\nsymbol: public(String[32])\ndecimals: public(uint256)\n\nbalanceOf: public(HashMap[address, uint256])\nallowance: public(HashMap[address, HashMap[address, uint256]])\ntotalSupply: public(uint256)\nminter: address\n_supply: uint256\n_check: uint256 #1% of the total supply check\n\n\n@external\ndef __init__():\n    self._supply = 10_000_000_000 \n    self._check = 100_000_000\n    self.decimals = 18\n    self.name = 'Kooopa'\n    self.symbol = 'KOO'\n    \n    init_supply: uint256 = self._supply * 10 ** self.decimals\n    \n    self.balanceOf[msg.sender] = init_supply\n    self.totalSupply = init_supply\n    self.minter = msg.sender\n\n    log Transfer(ZERO_ADDRESS, msg.sender, init_supply)\n\n\n@internal\ndef _transfer(_from : address, _to : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Transfer limit of 1%(100 Million) Tokens'\n\n    TargetBalance: uint256 = self.balanceOf[_to] + _value\n    assert TargetBalance <= self._check, 'Single wallet cannot hold more than 1%(100 Million) Tokens'\n\n    self.balanceOf[_from] -= _value\n    self.balanceOf[_to] += _value\n    log Transfer(_from, _to, _value)\n    return True\n\n\n@external\ndef transfer(_to : address, _value : uint256) -> bool:\n    self._transfer(msg.sender, _to, _value)\n    return True\n\n\n@external\ndef transferFrom(_from : address, _to : address, _value : uint256) -> bool:\n    self._transfer(_from, _to, _value)\n    self.allowance[_from][msg.sender] -= _value\n    return True\n\n\n@external\ndef approve(_spender : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Cant Approve more than 1%(100 Million) Tokens for transfer'\n\n    self.allowance[msg.sender][_spender] = _value\n    log Approval(msg.sender, _spender, _value)\n    return True\n\n\n@external\ndef mint(_to: address, _value: uint256):\n    assert msg.sender == self.minter\n    assert _to != ZERO_ADDRESS\n    self.totalSupply += _value\n    self.balanceOf[_to] += _value\n    log Transfer(ZERO_ADDRESS, _to, _value)\n\n\n@internal\ndef _burn(_to: address, _value: uint256):\n    \n    assert _to != ZERO_ADDRESS\n    self.totalSupply -= _value\n    self.balanceOf[_to] -= _value\n    log Transfer(_to, ZERO_ADDRESS, _value)\n\n\n@external\ndef burn(_value: uint256):\n    self._burn(msg.sender, _value)\n\n\n@external\ndef burnFrom(_to: address, _value: uint256):\n    self.allowance[_to][msg.sender] -= _value\n    self._burn(_to, _value)","constructor_args":null,"contract_name":"Storage","evm_version":"istanbul"}`
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0xd73249995040f04cb891bdf0f997579ee3a6676c/verification/via/vyper-code HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: application/json
  Accept: */*
  Content-Length: 2891

  {
    "compiler_version": "v0.2.12+commit.2c6842c",
    "license_type": "gnu_agpl_v3",
    "source_code": "from vyper.interfaces import ERC20\n\nimplements: ERC20\n\nevent Transfer:\n    sender: indexed(address)\n    receiver: indexed(address)\n    value: uint256\n\nevent Approval:\n    owner: indexed(address)\n    spender: indexed(address)\n    value: uint256\n\nname: public(String[64])\nsymbol: public(String[32])\ndecimals: public(uint256)\n\nbalanceOf: public(HashMap[address, uint256])\nallowance: public(HashMap[address, HashMap[address, uint256]])\ntotalSupply: public(uint256)\nminter: address\n_supply: uint256\n_check: uint256 #1% of the total supply check\n\n\n@external\ndef __init__():\n    self._supply = 10_000_000_000 \n    self._check = 100_000_000\n    self.decimals = 18\n    self.name = 'Kooopa'\n    self.symbol = 'KOO'\n    \n    init_supply: uint256 = self._supply * 10 ** self.decimals\n    \n    self.balanceOf[msg.sender] = init_supply\n    self.totalSupply = init_supply\n    self.minter = msg.sender\n\n    log Transfer(ZERO_ADDRESS, msg.sender, init_supply)\n\n\n@internal\ndef _transfer(_from : address, _to : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Transfer limit of 1%(100 Million) Tokens'\n\n    TargetBalance: uint256 = self.balanceOf[_to] + _value\n    assert TargetBalance <= self._check, 'Single wallet cannot hold more than 1%(100 Million) Tokens'\n\n    self.balanceOf[_from] -= _value\n    self.balanceOf[_to] += _value\n    log Transfer(_from, _to, _value)\n    return True\n\n\n@external\ndef transfer(_to : address, _value : uint256) -> bool:\n    self._transfer(msg.sender, _to, _value)\n    return True\n\n\n@external\ndef transferFrom(_from : address, _to : address, _value : uint256) -> bool:\n    self._transfer(_from, _to, _value)\n    self.allowance[_from][msg.sender] -= _value\n    return True\n\n\n@external\ndef approve(_spender : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Cant Approve more than 1%(100 Million) Tokens for transfer'\n\n    self.allowance[msg.sender][_spender] = _value\n    log Approval(msg.sender, _spender, _value)\n    return True\n\n\n@external\ndef mint(_to: address, _value: uint256):\n    assert msg.sender == self.minter\n    assert _to != ZERO_ADDRESS\n    self.totalSupply += _value\n    self.balanceOf[_to] += _value\n    log Transfer(ZERO_ADDRESS, _to, _value)\n\n\n@internal\ndef _burn(_to: address, _value: uint256):\n    \n    assert _to != ZERO_ADDRESS\n    self.totalSupply -= _value\n    self.balanceOf[_to] -= _value\n    log Transfer(_to, ZERO_ADDRESS, _value)\n\n\n@external\ndef burn(_value: uint256):\n    self._burn(msg.sender, _value)\n\n\n@external\ndef burnFrom(_to: address, _value: uint256):\n    self.allowance[_to][msg.sender] -= _value\n    self._burn(_to, _value)",
    "constructor_args": null,
    "contract_name": "Storage",
    "evm_version": "istanbul"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0xd73249995040f04cb891bdf0f997579ee3a6676c/verification/via/vyper-code' \
    --header 'Content-Type: application/json' \
    --data '{
      "compiler_version": "v0.2.12+commit.2c6842c",
      "license_type": "gnu_agpl_v3",
      "source_code": "from vyper.interfaces import ERC20

    implements: ERC20

    event Transfer:
        sender: indexed(address)
        receiver: indexed(address)
        value: uint256

    event Approval:
        owner: indexed(address)
        spender: indexed(address)
        value: uint256

    name: public(String[64])
    symbol: public(String[32])
    decimals: public(uint256)

    balanceOf: public(HashMap[address, uint256])
    allowance: public(HashMap[address, HashMap[address, uint256]])
    totalSupply: public(uint256)
    minter: address
    _supply: uint256
    _check: uint256 #1% of the total supply check


    @external
    def __init__():
        self._supply = 10_000_000_000 
        self._check = 100_000_000
        self.decimals = 18
        self.name = 'Kooopa'
        self.symbol = 'KOO'
        
        init_supply: uint256 = self._supply * 10 ** self.decimals
        
        self.balanceOf[msg.sender] = init_supply
        self.totalSupply = init_supply
        self.minter = msg.sender

        log Transfer(ZERO_ADDRESS, msg.sender, init_supply)


    @internal
    def _transfer(_from : address, _to : address, _value : uint256) -> bool:
        assert _value <= self._check, 'Transfer limit of 1%(100 Million) Tokens'

        TargetBalance: uint256 = self.balanceOf[_to] + _value
        assert TargetBalance <= self._check, 'Single wallet cannot hold more than 1%(100 Million) Tokens'

        self.balanceOf[_from] -= _value
        self.balanceOf[_to] += _value
        log Transfer(_from, _to, _value)
        return True


    @external
    def transfer(_to : address, _value : uint256) -> bool:
        self._transfer(msg.sender, _to, _value)
        return True


    @external
    def transferFrom(_from : address, _to : address, _value : uint256) -> bool:
        self._transfer(_from, _to, _value)
        self.allowance[_from][msg.sender] -= _value
        return True


    @external
    def approve(_spender : address, _value : uint256) -> bool:
        assert _value <= self._check, 'Cant Approve more than 1%(100 Million) Tokens for transfer'

        self.allowance[msg.sender][_spender] = _value
        log Approval(msg.sender, _spender, _value)
        return True


    @external
    def mint(_to: address, _value: uint256):
        assert msg.sender == self.minter
        assert _to != ZERO_ADDRESS
        self.totalSupply += _value
        self.balanceOf[_to] += _value
        log Transfer(ZERO_ADDRESS, _to, _value)


    @internal
    def _burn(_to: address, _value: uint256):
        
        assert _to != ZERO_ADDRESS
        self.totalSupply -= _value
        self.balanceOf[_to] -= _value
        log Transfer(_to, ZERO_ADDRESS, _value)


    @external
    def burn(_value: uint256):
        self._burn(msg.sender, _value)


    @external
    def burnFrom(_to: address, _value: uint256):
        self.allowance[_to][msg.sender] -= _value
        self._burn(_to, _value)",
      "constructor_args": null,
      "contract_name": "Storage",
      "evm_version": "istanbul"
    }'
  ```

  ```js JavaScript theme={null}
  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0xd73249995040f04cb891bdf0f997579ee3a6676c/verification/via/vyper-code', {
      method: 'POST',
      headers: {
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        "compiler_version": "v0.2.12+commit.2c6842c",
        "license_type": "gnu_agpl_v3",
        "source_code": "from vyper.interfaces import ERC20\n\nimplements: ERC20\n\nevent Transfer:\n    sender: indexed(address)\n    receiver: indexed(address)\n    value: uint256\n\nevent Approval:\n    owner: indexed(address)\n    spender: indexed(address)\n    value: uint256\n\nname: public(String[64])\nsymbol: public(String[32])\ndecimals: public(uint256)\n\nbalanceOf: public(HashMap[address, uint256])\nallowance: public(HashMap[address, HashMap[address, uint256]])\ntotalSupply: public(uint256)\nminter: address\n_supply: uint256\n_check: uint256 #1% of the total supply check\n\n\n@external\ndef __init__():\n    self._supply = 10_000_000_000 \n    self._check = 100_000_000\n    self.decimals = 18\n    self.name = 'Kooopa'\n    self.symbol = 'KOO'\n    \n    init_supply: uint256 = self._supply * 10 ** self.decimals\n    \n    self.balanceOf[msg.sender] = init_supply\n    self.totalSupply = init_supply\n    self.minter = msg.sender\n\n    log Transfer(ZERO_ADDRESS, msg.sender, init_supply)\n\n\n@internal\ndef _transfer(_from : address, _to : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Transfer limit of 1%(100 Million) Tokens'\n\n    TargetBalance: uint256 = self.balanceOf[_to] + _value\n    assert TargetBalance <= self._check, 'Single wallet cannot hold more than 1%(100 Million) Tokens'\n\n    self.balanceOf[_from] -= _value\n    self.balanceOf[_to] += _value\n    log Transfer(_from, _to, _value)\n    return True\n\n\n@external\ndef transfer(_to : address, _value : uint256) -> bool:\n    self._transfer(msg.sender, _to, _value)\n    return True\n\n\n@external\ndef transferFrom(_from : address, _to : address, _value : uint256) -> bool:\n    self._transfer(_from, _to, _value)\n    self.allowance[_from][msg.sender] -= _value\n    return True\n\n\n@external\ndef approve(_spender : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Cant Approve more than 1%(100 Million) Tokens for transfer'\n\n    self.allowance[msg.sender][_spender] = _value\n    log Approval(msg.sender, _spender, _value)\n    return True\n\n\n@external\ndef mint(_to: address, _value: uint256):\n    assert msg.sender == self.minter\n    assert _to != ZERO_ADDRESS\n    self.totalSupply += _value\n    self.balanceOf[_to] += _value\n    log Transfer(ZERO_ADDRESS, _to, _value)\n\n\n@internal\ndef _burn(_to: address, _value: uint256):\n    \n    assert _to != ZERO_ADDRESS\n    self.totalSupply -= _value\n    self.balanceOf[_to] -= _value\n    log Transfer(_to, ZERO_ADDRESS, _value)\n\n\n@external\ndef burn(_value: uint256):\n    self._burn(msg.sender, _value)\n\n\n@external\ndef burnFrom(_to: address, _value: uint256):\n    self.allowance[_to][msg.sender] -= _value\n    self._burn(_to, _value)",
        "constructor_args": null,
        "contract_name": "Storage",
        "evm_version": "istanbul"
      })
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0xd73249995040f04cb891bdf0f997579ee3a6676c/verification/via/vyper-code",
      headers={"Content-Type":"application/json"},
      data=json.dumps({
        "compiler_version": "v0.2.12+commit.2c6842c",
        "license_type": "gnu_agpl_v3",
        "source_code": "from vyper.interfaces import ERC20\n\nimplements: ERC20\n\nevent Transfer:\n    sender: indexed(address)\n    receiver: indexed(address)\n    value: uint256\n\nevent Approval:\n    owner: indexed(address)\n    spender: indexed(address)\n    value: uint256\n\nname: public(String[64])\nsymbol: public(String[32])\ndecimals: public(uint256)\n\nbalanceOf: public(HashMap[address, uint256])\nallowance: public(HashMap[address, HashMap[address, uint256]])\ntotalSupply: public(uint256)\nminter: address\n_supply: uint256\n_check: uint256 #1% of the total supply check\n\n\n@external\ndef __init__():\n    self._supply = 10_000_000_000 \n    self._check = 100_000_000\n    self.decimals = 18\n    self.name = 'Kooopa'\n    self.symbol = 'KOO'\n    \n    init_supply: uint256 = self._supply * 10 ** self.decimals\n    \n    self.balanceOf[msg.sender] = init_supply\n    self.totalSupply = init_supply\n    self.minter = msg.sender\n\n    log Transfer(ZERO_ADDRESS, msg.sender, init_supply)\n\n\n@internal\ndef _transfer(_from : address, _to : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Transfer limit of 1%(100 Million) Tokens'\n\n    TargetBalance: uint256 = self.balanceOf[_to] + _value\n    assert TargetBalance <= self._check, 'Single wallet cannot hold more than 1%(100 Million) Tokens'\n\n    self.balanceOf[_from] -= _value\n    self.balanceOf[_to] += _value\n    log Transfer(_from, _to, _value)\n    return True\n\n\n@external\ndef transfer(_to : address, _value : uint256) -> bool:\n    self._transfer(msg.sender, _to, _value)\n    return True\n\n\n@external\ndef transferFrom(_from : address, _to : address, _value : uint256) -> bool:\n    self._transfer(_from, _to, _value)\n    self.allowance[_from][msg.sender] -= _value\n    return True\n\n\n@external\ndef approve(_spender : address, _value : uint256) -> bool:\n    assert _value <= self._check, 'Cant Approve more than 1%(100 Million) Tokens for transfer'\n\n    self.allowance[msg.sender][_spender] = _value\n    log Approval(msg.sender, _spender, _value)\n    return True\n\n\n@external\ndef mint(_to: address, _value: uint256):\n    assert msg.sender == self.minter\n    assert _to != ZERO_ADDRESS\n    self.totalSupply += _value\n    self.balanceOf[_to] += _value\n    log Transfer(ZERO_ADDRESS, _to, _value)\n\n\n@internal\ndef _burn(_to: address, _value: uint256):\n    \n    assert _to != ZERO_ADDRESS\n    self.totalSupply -= _value\n    self.balanceOf[_to] -= _value\n    log Transfer(_to, ZERO_ADDRESS, _value)\n\n\n@external\ndef burn(_value: uint256):\n    self._burn(msg.sender, _value)\n\n\n@external\ndef burnFrom(_to: address, _value: uint256):\n    self.allowance[_to][msg.sender] -= _value\n    self._burn(_to, _value)",
        "constructor_args": None,
        "contract_name": "Storage",
        "evm_version": "istanbul"
      })
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Vyper Multi-part files

### verification multipart vyper

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-multi-part`

**Body**

<ParamField type="number">
  Example: `v0.3.7+commit.6020b8bb`
</ParamField>

<ParamField type="string">
  Example: `gnu_lgpl_v2_1`
</ParamField>

<ParamField type="string">
  Example: `istanbul`
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-multi-part HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: multipart/form-data
  Accept: */*
  Content-Length: 216

  {
    "compiler_version": "v0.3.7+commit.6020b8bb",
    "license_type": "gnu_lgpl_v2_1",
    "evm_version": "istanbul",
    "files[0]": "binary",
    "files[1]": "binary",
    "interfaces[0]": "binary",
    "interfaces[1]": "binary",
    "interfaces[2]": "binary"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-multi-part' \
    --header 'Content-Type: multipart/form-data' \
    --form 'compiler_version=v0.3.7+commit.6020b8bb' \
    --form 'license_type=gnu_lgpl_v2_1' \
    --form 'evm_version=istanbul' \
    --form 'files[0]=binary' \
    --form 'files[1]=binary' \
    --form 'interfaces[0]=binary' \
    --form 'interfaces[1]=binary' \
    --form 'interfaces[2]=binary'
  ```

  ```js JavaScript theme={null}
  const formData = new FormData();

  formData.append("compiler_version", "v0.3.7+commit.6020b8bb");
  formData.append("license_type", "gnu_lgpl_v2_1");
  formData.append("evm_version", "istanbul");
  formData.append("files[0]", "binary");
  formData.append("files[1]", "binary");
  formData.append("interfaces[0]", "binary");
  formData.append("interfaces[1]", "binary");
  formData.append("interfaces[2]", "binary");

  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-multi-part', {
      method: 'POST',
      headers: {
        "Content-Type": "multipart/form-data"
      },
      body: formData
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  files = {
      "compiler_version": "v0.3.7+commit.6020b8bb",
      "license_type": "gnu_lgpl_v2_1",
      "evm_version": "istanbul",
      "files[0]": "binary",
      "files[1]": "binary",
      "interfaces[0]": "binary",
      "interfaces[1]": "binary",
      "interfaces[2]": "binary",
  }

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-multi-part",
      headers={"Content-Type":"multipart/form-data"},
      files=files
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```

## Vyper Standard JSON input

### verification standard json vyper

`POST` `https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-standard-input`

**Body**

<ParamField type="number">
  Example: `v0.2.7+commit.0b3f3b3`
</ParamField>

<ParamField type="string">
  Example: `gnu_lgpl_v3`
</ParamField>

<ParamField type="string">
  Example: `istanbul`
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

<ParamField type="string . binary">
   
</ParamField>

**Responses**

<Accordion title="200 Successful response">
   
</Accordion>

<CodeGroup>
  ```http HTTP theme={null}
  POST /api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-standard-input HTTP/1.1
  Host: eth.blockscout.com
  Content-Type: multipart/form-data
  Accept: */*
  Content-Length: 138

  {
    "compiler_version": "v0.2.7+commit.0b3f3b3",
    "license_type": "gnu_lgpl_v3",
    "evm_version": "istanbul",
    "files[0]": "binary",
    "files[1]": "binary"
  }
  ```

  ```sh cURL theme={null}
  curl -L \
    --request POST \
    --url 'https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-standard-input' \
    --header 'Content-Type: multipart/form-data' \
    --form 'compiler_version=v0.2.7+commit.0b3f3b3' \
    --form 'license_type=gnu_lgpl_v3' \
    --form 'evm_version=istanbul' \
    --form 'files[0]=binary' \
    --form 'files[1]=binary'
  ```

  ```js JavaScript theme={null}
  const formData = new FormData();

  formData.append("compiler_version", "v0.2.7+commit.0b3f3b3");
  formData.append("license_type", "gnu_lgpl_v3");
  formData.append("evm_version", "istanbul");
  formData.append("files[0]", "binary");
  formData.append("files[1]", "binary");

  const response = await fetch('https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-standard-input', {
      method: 'POST',
      headers: {
        "Content-Type": "multipart/form-data"
      },
      body: formData
  });

  const data = await response.json();
  ```

  ```py Python theme={null}
  import requests

  files = {
      "compiler_version": "v0.2.7+commit.0b3f3b3",
      "license_type": "gnu_lgpl_v3",
      "evm_version": "istanbul",
      "files[0]": "binary",
      "files[1]": "binary",
  }

  response = requests.post(
      "https://eth.blockscout.com/api/v2/smart-contracts/0xc3fd3c09d5481f4d6c85e70775804de4c93fe630/verification/via/vyper-standard-input",
      headers={"Content-Type":"multipart/form-data"},
      files=files
  )

  data = response.json()
  ```
</CodeGroup>

```json 200 Successful Response theme={null}
No content
```


# Blockscout UI
Source: https://docs.blockscout.com/devs/verification/blockscout-ui



Verification is available for both Solidity and Vyper contracts. **Currently, there are 7 different type of inputs you can use for verification using the Blockscout UI.**

<Info>
  👷🏻‍♂️ If preferred you can verify directly from your Hardhat or Foundry dev environment.

  * [Hardhat Verification Plugin](/devs/verification/hardhat-verification-plugin)
  * [Foundry Verification](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify)
</Info>

<Check>
  To learn more about the smart contract verification Rust microservice and verification algorithm [see this page for developers](/setup/microservices/smart-contract-verification).
</Check>

## Smart Contract Verification with Blockscout

1. Go to the Verify contract page *(Other -> Verify contract)*

<Frame>
  <img alt="" />
</Frame>

2. Enter in the contract address you received during deployment. The dropdown will show you several available verification options. Select the one you would like to use and continue.

<Frame>
  <img alt="" />
</Frame>

* [Solidity (Flattened source code)](/devs/verification#via-flattened-source-code)
* [Solidity (Standard JSON input)](/devs/verification/blockscout-ui#via-standard-json-input)
* [Solidity (Sourcify)](/devs/verification/contracts-verification-via-sourcify)
* [Solidity (Multi-part files)](/devs/verification/blockscout-ui#solidity-multi-part-files)
* [Vyper (Contract)](/devs/verification#vyper-contract)
* [Vyper (Multi-part files)](/devs/verification/blockscout-ui#vyper-multi-part-files-and-standard-json-input)
* [Vyper (Standard JSON input)](/devs/verification/blockscout-ui#vyper-multi-part-files-and-standard-json-input)

### Solidity (Flattened source code)

This verification method is recommended only for a single-file smart contract without any imports. For verification of contracts containing more that 1 file, a different verification method is recommended.

<Frame>
  <img alt="" />
</Frame>

1. **Contract Address:** The `0x` address supplied on contract creation (added above)
2. **Is Yul contract:** Select if the contract is coded in Yul for efficiency.
3. **Include Nightly Builds**: Select if you want to show nightly builds.
4. **Compiler:** derived from the first line in the contract `pragma solidity X.X.X`. Use the corresponding compiler version rather than the nightly build.
5. **EVM Version:** Select the correct[EVM version](/setup/information-and-settings/evm-version-information)if known, otherwise use default.
6. **Optimization Enabled:** If you enabled optimization during compilation, select and enter the run value. 200 is the Solidity Compiler default value. Only change if you changed this value while compiling.
7. **Enter the Solidity Contract Code:** Copy-paste the source code of your smart contract as is.
8. **Add Contract Libraries:** Enter the name and 0x address for any required libraries called in the .sol file. You can add multiple contracts with the "+" button.
9. Click the `Verify and Publish` button.
10. If all goes well, you will see a checkmark ✅ next to Code in the code tab, and an additional tab called `Read Contract`. The contract name will now appear in BlockScout with any transactions related to your contract.

### Solidity (Standard JSON input)

<Info>
  [More information on JSON input is available here](https://docs.soliditylang.org/en/latest/using-the-compiler.html#input-description).
</Info>

1. **Include nightly builds**. You can choose **Yes** or **No** depending on your compiler.
2. **Compiler.** Choose the compiler version used to compile your smart contract. If you selected yes for nightly builds, use the compiler version rather than the build.
3. **Standard Input JSON.** Upload your Standard Input JSON file. File should follows solidity [format](https://docs.soliditylang.org/en/latest/using-the-compiler.html#input-description) and all the sources must be in Literal Content format, not a URL.

Click the **Verify & publish** button and wait for the response.

### Via Sourcify: Sources and metadata JSON file

See the [Contract Verification via Sourcify](/devs/verification/contracts-verification-via-sourcify) page for details.

### Solidity (Multi-part files)

See the above settings. You will upload all of the .sol or .yul files you used for your contract. This method requires at least 2 files - if you have a single file use the flattened source code method.

### Vyper Contract

1. **Contract Name:** Name assigned to the contract.
2. **Compiler**: Select the compiler version used in the source code.
3. **EVM Version:** Select the correct [EVM version](/setup/information-and-settings/evm-version-information) if known, otherwise use default.
4. **Contract Code:** Copy and paste the contract code
5. Click the `Verify and Publish` button.

If all goes well, you will see a checkmark ✅ next to Code in the code tab, and an additional tab called `Read Contract`. The contract name will now appear in BlockScout with any transactions related to your contract.

### Vyper Multi-part files and standard json input

See the information above.

## Troubleshooting

If you receive the dreaded `There was an error compiling your contract` message this means the bytecode doesn't match the supplied sourcecode. Unfortunately, there are many reasons this may be the case. Here are a few things to try:

1. Double check the compiler version is correct.

<Info>
  Check all version digits - for example 0.5.1 is different from 0.5.10
</Info>

2. Check that an extra space has not been added to the end of the contract. When pasting in, an extra space may be added. Delete this and attempt to recompile.

3. Copy, paste, and verify your source code in Remix. You may find some exceptions here.

### Verification in a dev environment

The [Hardhat verification plugin](/devs/verification/hardhat-verification-plugin) supports BlockScout. You can also choose to use the [Sourcify plugin](/devs/verification/hardhat-verification-plugin/sourcify-plugin-for-hardhat) to verify with Sourcify from your hardhat environment. [Foundry supports blockscout verification with Forge](https://book.getfoundry.sh/reference/forge/forge-verify-contract).


# Sourcify Verification
Source: https://docs.blockscout.com/devs/verification/contracts-verification-via-sourcify



Along with contract verification through a flattened source file (the default option in Blockscout), a [Sourcify](https://sourcify.dev/) verification option through their UI is also available.

## Usage Example

Verify your contract using Sourcify:

1\) Go to the Verify contract page *(Other -> Verify contract)*

<Frame>
  <img />
</Frame>

2\) Enter the deployed contract address, select Sourcify (Solidity or Vyper) from the Verification method dropdown.

<Frame>
  <img />
</Frame>

3\) Now follow the instructions inside the Sourcify widget. Select the smart contract language of the source code and a verification method.

<Frame>
  <img />
</Frame>

4\) Upload or paste your contract source code according to the selected verification method. In the example, we paste the contract sources as Std Json into the text box. Select the compiler version and contract identifier.

Once all information is provided, start the verification by clicking the Verify Contract button.

<Frame>
  <img />
</Frame>

5\) You can follow the verification process by clicking on the View Job Status button.

After several seconds your contract should be verified through Sourcify's API (If verification fails, you will see the reason in the job status page). Verification metadata will be saved in the Blockscout DB and you will see the verified contract page with the link to the same metadata in the [Sourcify contract repository](https://repo.sourcify.dev/).

<Frame>
  <img />
</Frame>

### Example Contract:

* Contract [verified in Blockscout](https://gnosis.blockscout.com/address/0x4f15a6e74CFC2F80D5967a8aB75F3c83D8043cF4?tab=contract)

* The same contract in the [Sourcify contract repository](https://repo.sourcify.dev/contracts/full_match/100/0x4f15a6e74CFC2F80D5967a8aB75F3c83D8043cF4/).


# Foundry Verification
Source: https://docs.blockscout.com/devs/verification/foundry-verification



[Foundry](https://github.com/foundry-rs/foundry/) is a smart contract development toolchain. Foundry manages your dependencies, compiles your project, runs tests, deploys, and lets you interact with the chain from the command line and via Solidity scripts.

Forge is a command-line tool that ships with Foundry. Forge tests, builds, and deploys your smart contracts. Forge supports contract verification out of the box ([https://book.getfoundry.sh/reference/forge/forge-verify-contract](https://book.getfoundry.sh/reference/forge/forge-verify-contract))

## Verify contract

In forge, contracts can be verified at the time of the deployment (e.g. using `forge script`), or later, if the contracts are already deployed (e.g. using `forge verify-contract`).

#### Tips:

1. Specify the `—verifier=blockscout` flag to use the Blockscout verification provider. API key for Blockscout verification is optional.

2. Specify the `--verifier-url=<blockscout_homepage_explorer_url>/api/` flag for connecting to a specific Blockscout instance (e.g., `--verifier-url=https://eth-sepolia.blockscout.com/api/`).

3. You can specify most configuration options (e.g., evm version, disabling optimizations) via the usual Forge configuration (see [https://github.com/foundry-rs/foundry/blob/master/config/README.md](https://github.com/foundry-rs/foundry/blob/master/config/README.md)).

### Example (Deploy and verify)

Verify a contract with Blockscout right after deployment (make sure you add "/api/" to the end of the Blockscout homepage explorer URL):

```sh theme={null}
forge create \
  --rpc-url <rpc_https_endpoint> \
  --private-key $PRIVATE_KEY \
  <contract_file>:<contract_name> \
  --verify \
  --verifier blockscout \
  --verifier-url <blockscout_homepage_explorer_url>/api/
```

Or if using foundry scripts:

```sh theme={null}
forge script <script_file> \
  --rpc-url <rpc_https_endpoint> \
  --private-key $PRIVATE_KEY \
  --broadcast \
  --verify \
  --verifier blockscout \
  --verifier-url <blockscout_homepage_explorer_url>/api/
```

### Example (Verify already deployed contract)

```sh theme={null}
forge verify-contract \
  --rpc-url <rpc_https_endpoint> \
  <address> \
  <contract_file>:<contract_name> \
  --verifier blockscout \
  --verifier-url <blockscout_homepage_explorer_url>/api/
```

Or if using foundry scripts for last executed script run:

```sh theme={null}
forge script <script_file> \
  --rpc-url <rpc_https_endpoint> \
  --private-key $PRIVATE_KEY \
  --resume \
  --verify \
  --verifier blockscout \
  --verifier-url <blockscout_homepage_explorer_url>/api/
```


# Hardhat Verification Plugin
Source: https://docs.blockscout.com/devs/verification/hardhat-verification-plugin



[Hardhat](https://hardhat.org/) is a full-featured development environment for contract compilation, deployment and verification. The [hardhat-verify plugin](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify) supports contract verification on Blockscout.

## Get Started

### **1) Install Hardhat**

If you are starting from scratch, create an npm project by going to an empty folder, running `npm init`, and following the instructions. Recommend npm 7 or higher.

Once your project is ready:

**npm instructions**

```sh theme={null}
npm install --save-dev hardhat
```

**yarn instructions**

```sh theme={null}
yarn add --dev hardhat
```

### **2) Create a project**

Run `npx hardhat` in your project folder and follow the instructions to create ([more info here](https://hardhat.org/getting-started/#quick-start)).

### 3) Install plugin

Install the [hardhat-verify plugin](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify)

**npm**

```sh theme={null}
npm install --save-dev @nomicfoundation/hardhat-verify
```

**yarn**

```sh theme={null}
yarn add --dev @nomicfoundation/hardhat-verify
```

### 4) Add plugin reference to config file

Add the following statement to your `hardhat.config.js`.

```javascript theme={null}
require("@nomicfoundation/hardhat-verify");
```

If using TypeScript, add this to your `hardhat.config.ts.` [More info on using typescript with hardhat available here](https://hardhat.org/guides/typescript.html#typescript-support).

```ts theme={null}
import "@nomicfoundation/hardhat-verify";
```

## Config File and Unsupported Networks

Your basic [Hardhat config file](https://hardhat.org/config/) (`hardhat.config.js` or `hardhat.config.ts`) will be setup to support the network you are working on. In this example we use the Optimism Sepolia test network and a `.js` file.

Here we add an RPC url without an API key, however some value is still required. You can use any arbitrary string. [More info](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify#multiple-api-keys-and-alternative-block-explorers).

If you prefer, you can migrate to [hardhat-toolbox](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-toolbox) to use a plugin bundle.

In order to use Blockscout explorer for the verification, you have to specify the explorer details under a `customChains` object. It includes:

* `chainID` - Network chain ID
* `apiURL` - Block explorer API URL
* `browserURL` - Block explorer URL

<Info>
  Find an extensive list of ChainIDs at [https://chainlist.org/](https://chainlist.org/).
</Info>

For example, here we added Blockscout api endpoints for the Optimism Sepolia network to the config file. Note the network name in `customChains` must match the network name in the `apiKey` object.

```javascript theme={null}
import { HardhatUserConfig } from "hardhat/config";
import "@nomicfoundation/hardhat-toolbox";
import "@nomicfoundation/hardhat-verify";

const PRIVATE_KEY = vars.get("PRIVATE_KEY");

const config: HardhatUserConfig = {
  solidity: "0.8.24",
  networks: {
    'optimism-sepolia': {
      url: 'https://sepolia.optimism.io',
      accounts: [PRIVATE_KEY],
    },
  },
  etherscan: {
    apiKey: {
      // Is not required by blockscout. Can be any non-empty string
      'optimism-sepolia': "abc"
    },
    customChains: [
      {
        network: "optimism-sepolia",
        chainId: 11155420,
        urls: {
          apiURL: "https://optimism-sepolia.blockscout.com/api",
          browserURL: "https://optimism-sepolia.blockscout.com/",
        }
      }
    ]
  },
  sourcify: {
    enabled: false
  }
};

export default config;
```

## Deploy and Verify

For deployment we will use [Hardhat Ignition](https://hardhat.org/ignition/docs/getting-started#overview) - built-in Hardhat deployment system.

### Deploy

```txt theme={null}
> npx hardhat ignition deploy ./ignition/modules/Lock.ts --network optimism-sepolia
✔ Confirm deploy to network optimism-sepolia (11155420)? … yes
Compiled 1 Solidity file successfully (evm target: paris).
Hardhat Ignition 🚀

Deploying [ LockModule ]

Batch #1
  Executed LockModule#Lock

[ LockModule ] successfully deployed 🚀

Deployed Addresses

LockModule#Lock - 0xFE826b33e425f99ce962ACB91752DB41F302EFEA
```

### Verify

The plugin requires you to include constructor arguments with the verify task and ensures that they correspond to expected ABI signature. However, Blockscout ignores those arguments, so you may specify any values that correspond to the ABI.

```sh theme={null}
npx hardhat verify --network <network> DEPLOYED_CONTRACT_ADDRESS "Constructor argument 1"
```

Optimism Sepolia example.

```sh theme={null}
> npx hardhat verify --network optimism-sepolia 0xFE826b33e425f99ce962ACB91752DB41F302EFEA 1234
Successfully submitted source code for contract
contracts/Lock.sol:Lock at 0xFE826b33e425f99ce962ACB91752DB41F302EFEA
for verification on the block explorer. Waiting for verification result...

Successfully verified contract Lock on the block explorer.
https://optimism-sepolia.blockscout.com/address/0xFE826b33e425f99ce962ACB91752DB41F302EFEA#code
```

### Automatically verified contracts

Sometimes the contract may be automatically verified via [Ethereum Bytecode Database](https://docs.blockscout.com/about/features/ethereum-bytecode-database-microservice#solution-ethereum-bytecode-database-blockscout-ebd) service. In that case you may see the following response:

```txt theme={null}
The contract 0xFE826b33e425f99ce962ACB91752DB41F302EFEA has already been verified on Etherscan.
https://optimism-sepolia.blockscout.com/address/0xFE826b33e425f99ce962ACB91752DB41F302EFEA#code
```

In that case, you may try to enforce using `--force` flag\*.

It prevents Hardhat from checking if the contract is already verified, and force it to send verification request anyway. Notice, that it is helpful only if the contract was automatically verified **partially**. That way, a new verification sources would be saved. If the contract was **fully** verified already, that just returns an error.

```sh theme={null}
npx hardhat verify --network <network> DEPLOYED_CONTRACT_ADDRESS "Constructor argument 1" --force
```

* The flag is available starting from `@nomicfoundation/hardhat-verify@2.0.7`

## Confirm Verification on BlockScout

Go to your BlockScout instance and paste the contract address into the search bar.

<Frame>
  <img alt="" />
</Frame>

Scroll down to see verified status. A green checkmark ✅ means the contract is verified.

<Frame>
  <img alt="" />
</Frame>

If your screen size is limited, you may need to click the 3 dots to view and click through to the contract.

<Frame>
  <img alt="" />
</Frame>

Scroll down to see and interact with the contract code.

<Frame>
  <img alt="" />
</Frame>

## Video example

Community video created by Carlos Rodriguez for the Soneium Minato testnet, but can be applicable to any chain.

<Frame>
  <iframe title="VERIFY a SMART CONTRACT on SONEIUM's TESTNET: MINATO" />
</Frame>

## FAQ

<Accordion title="I am using an OpenZeppelin upgrades plugin implementation and receive an error on proxy contract verification. What should I do?">
  Although you receive an error, the contracts should be verified during the previous steps and you can ignore. Check in the explorer to make sure the contracts have been verified.
</Accordion>

## Resources

<Info>
  Learn more about plugin configs, troubleshooting etc. at [https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify](https://hardhat.org/hardhat-runner/plugins/nomicfoundation-hardhat-verify)
</Info>


# Sourcify Plugin For Hardhat
Source: https://docs.blockscout.com/devs/verification/hardhat-verification-plugin/sourcify-plugin-for-hardhat



Similar to the [hardhat verification plugin](/devs/verification/hardhat-verification-plugin), this plugin submits the contract source and other info of all deployed contracts to Sourcify.

### Verify

Similar to the verification approach described in the [hardhat verification plugin](/devs/verification/hardhat-verification-plugin), you can verify the contract source code in Sourcify as well by setting the following in the hardhat config file:

```javascript theme={null}
// ...
const config: HardhatUserConfig = {
  // ...
  sourcify: {
    enabled: true
  },
  // ...
};

export default config;
```

```sh theme={null}
npx hardhat verify --network <network> DEPLOYED_CONTRACT_ADDRESS "Constructor argument 1"
```

Optimism Sepolia example:

```sh theme={null}
> npx hardhat verify --network optimism-sepolia 0xCD562a6426b474390A9E7e554b9B4f9f62Ea38Ba 1234
Successfully submitted source code for contract
contracts/Lock.sol:Lock at 0xCD562a6426b474390A9E7e554b9B4f9f62Ea38Ba
for verification on the block explorer. Waiting for verification result...

Successfully verified contract Lock on the block explorer.
https://optimism-sepolia.blockscout.com/address/0xCD562a6426b474390A9E7e554b9B4f9f62Ea38Ba#code

Successfully verified contract Lock on Sourcify.
https://repo.sourcify.dev/contracts/full_match/11155420/0xCD562a6426b474390A9E7e554b9B4f9f62Ea38Ba/
```

## Confirm Verification on Blockscout

Go to your BlockScout instance and paste the contract address into the search bar.

<Frame>
  <img alt="" />
</Frame>

Scroll down to see verified status. A green checkmark ✅ means the contract is verified.

<Frame>
  <img alt="" />
</Frame>

If your screen size is limited, you may need to click the 3 dots to view and click through to the contract.

<Frame>
  <img alt="" />
</Frame>

Scroll down to see and interact with the contract code.

<Frame>
  <img alt="" />
</Frame>


# Interacting with Smart Contracts
Source: https://docs.blockscout.com/devs/verification/interacting-with-smart-contracts

Use Blockscout to Read and Write to Smart Contracts

Once a contract is verified, contract methods are exposed and contract interaction is possible directly from Blockscout.

<Info>
  In the following examples we use Blockscout on Gnosis Chain. You can interact with verified contracts on any supported chain. Make sure your web3 wallet (like MetaMask) is also connected to that chain when reading / writing to a contract.
</Info>

## Read Contract

Read actions let you check various contract attributes. You will need to connect a web3 wallet to make a query, though a query does not require a transaction or any gas costs.

1\) Find the contract address you want to interact with and enter into the search bar. In this example we search for USDC on Gnosis Chain.

<Frame>
  <img />
</Frame>

2\) We select the first option in search and are taken to the token page. We can interact from here, but would prefer to see more information about the contract, so we click through to the contract page.

<Frame>
  <img />
</Frame>

3\) Scrolling down past the contract details we see the code is verified by the checkmark✅. If the code is not verified, it is not possible to read or write to a contract (unless a verified contract with the same bytecode is located in the Blockscout database. In this case read/write will also be available).

<Frame>
  <img />
</Frame>

4\) We know this is a proxy implementation by the fact that there are options to either read/write to the contract or to the proxy. Proxy means that the contract is upgradeable, and the admin can set a new proxy address for the primary contract if upgrades are required.

We will choose to **Read Proxy**, since it contains all the relevant methods for the current contract implementation.

<Frame>
  <img />
</Frame>

5\) We can see the various methods within the proxy contract. Some show current values and others are queryable. An easy example to query is 8) `balanceOf` method.

<Frame>
  <img />
</Frame>

6\) This method expects an address and will output an integer. Simply paste in an 0x address and press **Query** to see the balance in USDC held by that particular address. If your web3 wallet is not connected at this point, you will be prompted to connect.

<Frame>
  <img />
</Frame>

The result shows this address holds 1,000,000 of the token, which converts to 1 USDC. *(Note ERC20 tokens allow for custom decimal point precision. USDC uses 6 decimal precision. Many others use 18 (to denote wei) so be sure to check the token implementation for conversion info).*

## Write Contract

<Info>
  Many write functions can only be performed by an approved owner. Connect the owner wallet when performing gated functions.
</Info>

1\) We'll use Blockscout to transfer 0.50 USDC from 1 address to another. You can perform this action directly through a wallet UI, we use the Blockscout interface here for demonstration purposes. See steps 1-3 above for accessing USDC on Gnosis Chain, or simply type the contract address (*0xDDAfbb505ad214D7b80b1f830fcCc89B60fb7A83*) into the search bar. Scroll down and select **Write Proxy**.

<Frame>
  <img />
</Frame>

2\) We scroll down to find the `transferFrom` method.

<Frame>
  <img />
</Frame>

Boxes are filled with the following information:

1. `_sender(address)`: The `0x` address sending the USDC. Note this account is the one to connect to Blockscout to write to the contract.

2. `_recipient(address)`: The `0x` address receiving the USDC.

3. `_amount(uint256)`: Amount to transfer. We use 6 decimals of precision for USDC - for other tokens this can differ. Here we enter 500000 to denote \$0.50.

<Frame>
  <img />
</Frame>

3\) We press the **Write** button, and MetaMask or another web3 wallet takes us through the transaction. If a wallet is not connected, there will be several prompts to connect an account to Blockscout. Once connected, we confirm the transaction.

<Info>
  The connected wallet must contain enough native tokens (in this case xDai) to pay gas for the transaction.
</Info>

<Frame>
  <img />
</Frame>

4\) We can check our wallet to confirm the transaction, and can view tx details in Blockscout (or return to the [Read Contract](/devs/verification/interacting-with-smart-contracts#read-contract) `balanceOf` method to view new balances for the addresses).

<Frame>
  <img />
</Frame>

Transaction hash: [0x2c93c4e6618b30c552b95ce2eef16b6e663d99aa2f4a8ea55a70b693de70f113](https://gnosis.blockscout.com/tx/0x2c93c4e6618b30c552b95ce2eef16b6e663d99aa2f4a8ea55a70b693de70f113)

<Frame>
  <img />
</Frame>


# Remix Verification
Source: https://docs.blockscout.com/devs/verification/remix-verification



Since [v0.56.0](https://github.com/remix-project-org/remix-project/releases/tag/v0.56.0) Remix IDE comes with a built-in verification plugin that allows you to verify your contracts on multiple verifiers.

To verify your contracts on Remix:

* Turn on the plugin "CONTRACT VERIFICATION" from the plugin manager.
* On the File Explorer, select and compile the contract you want to verify.
* On the Contract Verification plugin, select the Contract Name, Chain, and input the contract address. Add constructor arguments if needed.
* Click "Verify". You can see the process on the "Receipts" tab.

You can find more information about the plugin in the [Remix documentation](https://remix-ide.readthedocs.io/en/latest/contract_verification.html#verify-page).


# Stylus Verification
Source: https://docs.blockscout.com/devs/verification/stylus-verification

Verify stylus contracts with the Blockscout API

<Note>
  The original article appeared in the [Stylus Saturdays blog](https://stylus-saturdays.com/p/how-to-verify-your-stylus-contracts)
</Note>

## **How to verify your Stylus contracts  using the Blockscout’s API**

We support verifying Stylus contracts located in public GitHub repositories. The swagger file for our API endpoint to request the verification can be found [<u>here</u>](https://app.swaggerhub.com/apis/blockscout-f58/stylus-verifier/v1#/StylusSdkRsVerifier/StylusSdkRsVerifier_VerifyGithubRepository). The endpoint accepts the following fields: `deployment_transaction`, `rpc_endpoint`, `cargo_stylus_version`, `repository_url`, `commit`, and `path_prefix`

The `path_prefix` is required so that repositories with several contract crates inside can be used. The repository [<u>https://github.com/blockscout/cargo-stylus-test-examples</u>](https://github.com/blockscout/cargo-stylus-test-examples) contains some great examples.

When a user visits the verification UI, they provide the `cargo_stylus_version`, `repository_url`, `commit`, and `path_prefix` values. These values, along with the address of the contract being verified, are sent to an Elixir backend. The backend retrieves the `deployment_transaction` from the internal database, and sends the data it collected so far, and the `rpc_endpoint`, to a separate verification service.

The service validates the repository, clones the repo the user provided, and checks out the commit hash. If `path_prefix` is provided, it enters the corresponding `prefix`, which is calculated relative to the repository root directory.

Stylus requires the Rust toolchain version to be specified in a `rust-toolchain.toml` file. The file has to be located inside the working directory.

For verification, Blockscout uses the command `cargo stylus verify` `--no-verify --endpoint {rpc_endpoint} --deployment-tx {deployment_transaction}`\`.

We opt out of running verification inside in-stylus docker container by adding the `--no-verify` flag. We opt out because `cargo-stylus` requires the docker daemon to be run locally, but we would like to run the service and docker daemon on different machines. We implemented our own docker container startup process which allows us to run containers on the remote docker daemon.

`cargo stylus verify` prints the result into console. We parse the `stdout` and look for the line: "`Verified - contract matches local project's file hashes`". If found, the verification is considered successful, otherwise the verification fails.

If successful, we also attempt to retrieve the contract ABI as it is not returned by the verify command. To get the abi, we run the `cargo stylus export-abi` command, and parse its result. It prints the ABIs of all included contracts, and the verified contract ABI is printed as the last one. The name of this ABI is also used as a contract name inside a response.

If you need the code, the main function is implemented here: [<u>https://github.com/blockscout/blockscout-rs/blob/main/stylus-verifier/stylus-verifier-logic/src/stylus\_sdk\_rs.rs#L76</u>](https://github.com/blockscout/blockscout-rs/blob/main/stylus-verifier/stylus-verifier-logic/src/stylus_sdk_rs.rs#L76)

An example of making a request to the Blockscout API for verification:

```bash theme={null}
curl 'https://arbitrum.blockscout.com/api/v2/smart-contracts/<address_hash>/verification/via/stylus-github-repository' -H 'Content-type: application/json' -d '{"cargo_stylus_version":"v0.5.6","repository_url":"https://github.com/OffchainLabs/stylus-erc20","commit":"d109002ffff3df7589cbbc92f8f104567a84f085","path_prefix":"","license_type":"none"}'
```


# Verification via thirdweb
Source: https://docs.blockscout.com/devs/verification/verification-via-thirdweb



[Thirdweb](https://thirdweb.com/) offers a complete web3 development kit including the ability to quickly deploy prebuilt contracts and start interacting with them on many chains. During this process flow it is also easy to verify contracts using Blockscout APIs.

<Check>
  [Follow these instructions to verify your contracts via the Blockscout API with thirdweb.](https://support.thirdweb.com/other-faqs/tFbbEYCSbJ1GTeXoPs4QFw/blockscout-api-contract-verification/qpa9r79QkgH31HFsvGissC)
</Check>


# Discord Channel
Source: https://docs.blockscout.com/discord-channel





# Discussion
Source: https://docs.blockscout.com/discussion





# Developer FAQs
Source: https://docs.blockscout.com/faqs/developer-faqs

FAQs for developers

## Developer FAQs

<AccordionGroup>
  <Accordion title="How do I run my own Blockscout explorer?">
    The easiest way is by using [<u>Autoscout</u>](https://deploy.blockscout.com/). Other methods are listed in [<u>https://docs.blockscout.com/setup/deployment</u>](https://docs.blockscout.com/setup/deployment)
  </Accordion>

  <Accordion title="How do I speed up my self-hosted instance?">
    BlockScout can be resource intensive. If your instance is running slowly:

    * clear the cache - the application cache is cleared on restart by running: `sudo systemctl restart explorer.service`
    * increase the memory limit for indexers using the [INDEXER\_MEMORY\_LIMIT](/setup/env-variables/backend-env-variables#indexer-management:~:text=INDEXER%5FMEMORY%5FLIMIT) ENV if indexing is slow.
    * increase the number of CPUs if CPU is running at 100% on the web app server
    * increase the memory if memory consumption is high on the web app server
    * increase the number of CPUs or/and increase the memory on the database server if consumption is high.

    Instructions for accessing and upgrading CPUs/memory will differ based on your setup. If you are running BlockScout on AWS, these settings can be accessed through your AWS services portal.
  </Accordion>

  <Accordion title="I want to use the latest version, how do I download it?">
    Use  `git clone https://github.com/blockscout/blockscout.git -b <version>`
  </Accordion>

  <Accordion title="How do I customize the coin symbol / name?">
    **Exchange Rates Coin Name**

    * Specify coin name for exchange rates fetcher with the `COIN` [ENV variables](/setup/env-variables)

    BlockScout utilizes the `COIN` environment variable which pulls the associated market data from the Coinmarketcap.com API or CoinGecko API to provide pricing data throughout the application.

    **Displayed Coin Symbol**

    In order to set displayed coin symbol, instance maintainer should set `COIN_NAME` runtime environment variable:

    ```
    export COIN_NAME=
    ```

    For instance, in case of POA instance of Blockscout:

    ```
    export COIN_NAME=POA
    ```
  </Accordion>

  <Accordion title="How do I manage deployment with AWS CodeDeploy?">
    1. Visit CodeDeploy in AWS. You will see a list of your deployments. Select the deployment id to view details `https://console.aws.amazon.com/codesuite/codedeploy/deployments?region=us-east-1`
    2. Deployment status consists of several steps. Once step 2 is complete (application is installed on replacement instances), you manually reroute traffic. Click the `Reroute traffic` button to initiate.

    <Frame>
      <img alt="" />
    </Frame>

    3. Once traffic is rerouted, you'll be asked to terminate the original instance. Click the **Terminate** button to initiate.

    <Frame>
      <img alt="" />
    </Frame>

    4. Once complete, use the public DNS address of the Amazon EC2 instance to view in a web browser. (To get the public DNS value, choose your Amazon EC2 instance in the Amazon EC2 console, and look for the value in **Public DNS** in the **Description** tab).
  </Accordion>

  <Accordion title="What's the best way to deploy to AWS?">
    Currently the best existing way is through docker compose [https://github.com/blockscout/blockscout/tree/master/docker-compose](https://github.com/blockscout/blockscout/tree/master/docker-compose).

    We are currently working on deployment through Kubernetes (K8s) and other methods for easily spinning up an instance on AWS.
  </Accordion>

  <Accordion title="How do I replace missing assets/version numbers?">
    #### Missing Assets

    1. Find the public ip of corresponding Blockscout instance in the EC2 -> Instances of AWS Dashboard.
    2. Connect to the host via SSH `ssh -i <host.pem> ec2-user@<public_ip>`, where `<host.pem>` is host's private key file, `<public_ip>` is the public ip of the host, that can be found in the AWS dashboard.
    3. Go to assets folder `cd /opt/app/apps/block_scout_web/priv/static`
    4. Add missing assets there or to `./images` folder depending on what is missing. Refresh Blockscout instance page. For example, if `favicon.ico` is missing in `./images` folder, just copy it from the root assets folder \`cp favicon.ico ./images/. You should see now the missing assets.

    #### Missing Version in Footer

    The app version number should be in the footer of BlockScout instance

    <Frame>
      <img alt="" />
    </Frame>

    1. Find the public ip of corresponding Blockscout instance in the EC2 -> Instances of AWS Dashboard
    2. Connect to the host via SSH `ssh -i <host.pem> ec2-user@<public_ip>`, where `<host.pem>` is host's private key file, `<public_ip>` is the public ip of the host, that can be found in the AWS dashboard.
    3. Go to layout folder `/opt/app/apps/block_scout_web/lib/block_scout_web/templates/layout`
    4. Open `_footer.html.eex` footer template in the favorite text editor. For example `nano ./_footer.html.eex` and fix the line `<% version = version() %>` (it is in the bottom of the file) with the hardcoded new version, for example, `<% version = 'v1.3.3-beta' %>` and save.
    5. Restart the Blockscout instance with `sudo systemctl restart explorer.service`
  </Accordion>

  <Accordion title="How do I fix the Gettext.Error?">
    You may receive this error after making changes to a specific BlockScout application.

    `(Gettext.Error) translation with msgid '...<msg_here>...' has a non-empty msgstr`

    To update gettext, run the following command **in the app's folder where the changes were made**.

    1. Go to the ./apps/name\_of\_app folder where the changes were made.
    2. Run `mix gettext.extract —merge`
    3. Repeat for other app folders as required.

    More information on Gettext is [available here](https://hexdocs.pm/gettext/Mix.Tasks.Gettext.Extract.html).
  </Accordion>

  <Accordion title="How do I update the UI?">
    See the [Branding configs](/setup/configuration-options/branding-configs) page for details related to different UI elements.

    For updates like adding elements/links etc you will need to change .eex templates. When changing .eex templates you don't need to rebuild. Run the application in dev mode (MIX\_ENV=dev), and change the template. You'll see changes on-the-fly. When changing js/scss while running the application, you need to run `mix phx.digest` to apply the changes.
  </Accordion>

  <Accordion title="How can I view smart contracts using RPC?">
    Use the JSON RPC `listcontracts` endpoint. For example, to view verified contracts, use the following query. Pagination is available

    ```sh theme={null}
    curl -X GET "
    https://gnosis.blockscout.com/api?module=contract&action=listcontracts&page=1&offset=50&filter=verified
    " -H "accept: application/json"
    ```
  </Accordion>

  <Accordion title="Why are Market Cap/Token Price stats wrong?">
    One reason may be related to the CoinGecko API refusing Blockscout requests without an API key.

    If impacted, apply this pull request to your instance:

    [https://github.com/blockscout/blockscout/pull/5613](https://github.com/blockscout/blockscout/pull/5613)

    It implements CoinGecko API key management and alternative CoinMarketCap exchange rates.
  </Accordion>

  <Accordion title="How do I verify contracts via an API?">
    There are several ways:

    * Use the [API v2 endpoints](/devs/verification/blockscout-smart-contract-verification-api)
    * Use the [RPC endpoints for verification](https://docs.blockscout.com/for-users/api/rpc-endpoints/contract#verify-a-contract-with-its-source-code-and-contract-creation-information)
  </Accordion>

  <Accordion title="How do I disable exchange rates?">
    Change the Explorer.ExchangeRates variable from `enabled: true` to `enabled: false`

    * config :explorer, Explorer.ExchangeRates, `enabled: false`, store: :ets

    [https://github.com/poanetwork/blockscout/blob/7aeecb2a04838cda0289a7fe432db74481cf575a/apps/explorer/config/config.exs#L32](https://github.com/poanetwork/blockscout/blob/7aeecb2a04838cda0289a7fe432db74481cf575a/apps/explorer/config/config.exs#L32)
  </Accordion>

  <Accordion title="How can I migrate verified contracts between databases?">
    You may want to do this if you are creating a new instance or resyncing a new node.

    1. Backup the `smart_contracts` table
    2. Restore this table following the resync.
  </Accordion>

  <Accordion title="Can I set RPC variable to a normal http(s) url?">
    Yes you can. The `ethereum_json_rpc_http` variable can be set to any url, it does not need to be a localhost. Client variant env variable should be specified in either case.
  </Accordion>

  <Accordion title="Do I need to enable ws?">
    No, it is not required. If ws is disabled, leave the `ETHEREUM_JSONRPC_WS_URL` env var empty or unset it.
  </Accordion>

  <Accordion title="How to fix error message &#x22;execution timeout at `pushGasToTopCall`&#x22;?">
    Try increasing time for the `ETHEREUM_JSONRPC_DEBUG_TRACE_TRANSACTION_TIMEOUT` [ENV variable](/setup/env-variables#indexer-management). The default is 5 sec.
  </Accordion>

  <Accordion title="How do I fix Unknown Private Network error?">
    In a self-hosted or locally deployed instance, when attempting to do a **write transaction** on a verified contract, the following errors may appear:

    **Unauthorized**

    "You connected to Unknown Private Network chain in the wallet, but the current instance of Blockscout is for Unknown Private Network chain"

    "No "from" address specified in neither the give options, nor the default options."

    **To Troubleshoot:**

    * Check that you set the correct `CHAIN_ID` env variable
    * Check correct variable for `NETWORK_ID`
  </Accordion>

  <Accordion title=" Is there an env variable for the favicon?">
    Yes, the [<u>FAVICON\_MASTER\_URL</u>](https://docs.blockscout.com/setup/env-variables/frontend-common-envs/envs#favicon:~:text=Version-,FAVICON_MASTER_URL,-string) ENV accepts a URL to a jpg/png/svg image.
  </Accordion>

  <Accordion title=" If I run my own local Blockscout explorer, it's gonna support ERC1155?">
    Yes, Blockscout supports ERC-20, ERC-721, ERC-1155 and ERC-404 token standards.
  </Accordion>

  <Accordion title="What Linux distro do you recommend for Blockscout manual deployment?">
    Ubuntu 24.04 has been configured in Blockscout CI
  </Accordion>

  <Accordion title="Is there a way to step through the code (debugging) using vscode?">
    We recommend using ElixirLS: Elixir support and debugger
  </Accordion>

  <Accordion title="I would like to customize Blockscout. Is there any docs or tutorial on that?">
    Some customization is available by setting environments variables [<u>https://docs.blockscout.com/setup/env-variables/backend-env-variables</u>](https://docs.blockscout.com/setup/env-variables/backend-env-variables).
  </Accordion>

  <Accordion title="Where can I get more info on defining specific variables for OP stack chains?">
    [https://blockscout.notion.site/OP-ENV-variable-values-defining-1003d73641f880b58e28ded1671256ab](https://blockscout.notion.site/OP-ENV-variable-values-defining-1003d73641f880b58e28ded1671256ab?source=copy_link)
  </Accordion>

  <Accordion title="Which frontend version should I use?">
    Use the compatibility table to find the correct version.  [<u>https://docs.blockscout.com/setup/requirements/back-front-compatibility-matrix</u>](https://docs.blockscout.com/setup/requirements/back-front-compatibility-matrix)
  </Accordion>

  <Accordion title="Can I use Cryptorank API v2 key for price fetching on Blockscout?">
    No, Blockscout uses a dedicated endpoint. Contact Cryptorank for API key.
  </Accordion>

  <Accordion title="How to connect to a local RPC node on a docker compose Blockscout instance?">
    Use  host.docker.internal instead of 127.0.0.1 e.g.

    [http://host.docker.internal:8545/](http://host.docker.internal:8545/)
  </Accordion>

  <Accordion title="How can I customize footer links?">
    The footer can be customized with the [NEXT\_PUBLIC\_FOOTER\_LINKS](https://docs.blockscout.com/setup/env-variables/frontend-common-envs/envs#footer) ENV.
  </Accordion>
</AccordionGroup>


# User FAQs
Source: https://docs.blockscout.com/faqs/faqs

FAQs for users

If you have a question that isn't answered here, please contact us in [our Discord](https://discord.gg/blockscout) and the team and community can help troubleshoot your issue.

## User FAQs

<AccordionGroup>
  <Accordion title="What does the &#x22;in&#x22; or &#x22;out&#x22; label mean on a transaction?">
    This label appears next to a transaction to signify whether a transaction was sent or received by a particular address.

    * **In:** A transaction was sent to the address
    * **Out** A transaction was initiated from the address

    <Frame>
      <img alt="" />
    </Frame>
  </Accordion>

  <Accordion title="What are the different transaction types?">
    **There are 3 transaction types which can be accessed from the tabs menu for an EOA (Externally Owned Address) or Smart Contract.**

    **Transactions:**

    An EOA, commonly known as a wallet address, initiates a transaction. Both incoming and outgoing transactions are recorded here, and includes any transaction that requires a gas fee (in the native token ETH, xDai etc) for execution.

    **Token Transfers:**

    Transactions of ERC-20 or ERC-721 tokens. This can include DeFi transactions (like adding or removing liquidity), EOA transfers, airdrops or other transactions where non-native tokens are sent and received.

    **Internal Transactions:**

    Transactions initiated and executed between smart contracts. Internal transactions are the result of an external transaction (EOA to contract). This initial transaction can then trigger many internal transactions between contracts as functions are called.

    <Frame>
      <img alt="" />
    </Frame>
  </Accordion>

  <Accordion title="What is CSV export error 504?">
    If you request too much data at the same time you may receive a timeout. Decreasing the period of time for an export (**1 week timeframe** is recommended for addresses with lots of transactions) can reduce these errors.
  </Accordion>

  <Accordion title="How can I access and read/write contract methods?">
    Yes! The contract should be verified (or the bytecode matches an existing contract) to enable reading and writing to contracts and proxy contracts. [More info here](/devs/verification/interacting-with-smart-contracts).
  </Accordion>

  <Accordion title="How do I verify a smart contract?">
    There are multiple methods including options from the Blockscout UI as well as an integration directly with Hardhat.

    **Blockscout UI:**

    * [Via flattened source code (Solidity)](/devs/verification#via-flattened-source-code)
    * [Via standard JSON input](/faqs/faqs#via-standard-json-input)
    * [Via Sourcify: Sources and metadata JSON file](/devs/verification/contracts-verification-via-sourcify)
    * [Vyper contract](/devs/verification#vyper-contract)

    **Hardhat:**

    * [Hardhat Verification Plugin](/devs/verification/hardhat-verification-plugin)
    * [Sourcify Plugin for Hardhat](/devs/verification/hardhat-verification-plugin/sourcify-plugin-for-hardhat)
  </Accordion>

  <Accordion title="Where can I find a list of all Blockscout explorers?">
    At [<u>https://chains.blockscout.com</u>](https://chains.blockscout.com)
  </Accordion>

  <Accordion title="How can I swap or bridge tokens?">
    Tokens can be swapped using [<u>https://swap.blockscout.com</u>](https://swap.blockscout.com)
  </Accordion>
</AccordionGroup>


# Integrating Blockscout into your Application
Source: https://docs.blockscout.com/get-started/integrating-data

Using APIs, SDK, and other tools with Blockscout

Blockscout features integration points for different applications.

## APIs

* [JSON-RPC API ](/devs/apis/rpc) calls that align with the Ethereum [JSON-RPC specifications](https://ethereum.org/en/developers/docs/apis/json-rpc/)
* [REST API](/devs/apis/rest) provides an intuitive interface for all explorer information
* [Additional microservice APIs](https://blockscout.github.io/swaggers/) includes items like the Blockscout name service, Merits, Contract Verifier and others.

## SDK

* The [Blockscout SDK](/devs/blockscout-sdk) provides access to simple explorer-based notifications directly into an application.

## MCP

* The [MCP Server](/devs/mcp-server) wraps Blockscout APIs and exposes blockchain data—balances, tokens, NFTs, contract metadata—via the Model Context Protocol (MCP) so that AI agents and tools (like Claude, Cursor, or IDEs) can access and analyze it contextually.

## Chainscout

* The [Chainscout list](/devs/chainscout-chains-list) provides a list of all known projects using Blockscout along with chain IDs and other relevant information.


# Migration Guide
Source: https://docs.blockscout.com/get-started/migration-guide

Whether you are a developer, project, or blockchain user, learn how to migrate from other explorers to Blockscout

<Accordion title="Why Switch to Blockscout?" icon="sparkles">
  * Blockscout is transparent, open-source software. Supported by the community for the community good.
  * Blockscout  adds new features regularly and offers support quickly.
  * Blockscout provides fast and reliable chain information, and robust APIs for developers.
  * Blockscout is a proven explorer with a long track record, ecosystem-wide support, high data availability, and a rich feature set
  *
  * other explorer do not offer.
</Accordion>

<Accordion title="Blockscout Features" icon="sparkles">
  * Deep Search
  * Advanced Contract Interaction
  * JSON RPC & REST APIs
  * User Operations
  * Dapp Marketplace
  * Enhanced Metadata
  * DEX tracker
  * Interop explorer in progress
</Accordion>

## Switching Links

Change links in your application to point to Blockscout

* **Update primary links**. Update all code within an application by replacing the front part of the url. <Icon icon="flag" /> [Link Switch Guide](/devs/replace-links)
* **Update wallet links**: Many wallets can be updated manually to switch the primary explorer link to Blockscout. <Icon icon="wallet" /> [Wallet Update Guide](https://www.blog.blockscout.com/changing-wallet-block-explorer-urls-to-blockscout/)
* **Link conversions**: Some Blockscout links are not 1-to-1 with Etherscan, mostly for newer features such as blobs and user ops. Expand to see the full link conversion table, and scroll horizontally to view all link information. <Icon icon="link" /> [URL Comparison Guide](https://blockscout.notion.site/2173d73641f8808db0a2c184ff2a6194?v=2173d73641f8801085d4000c046abd78\&pvs=143)

## API updates

No API key is required for Blockscout, but you can use our [free API key](/using-blockscout/my-account/api-keys) to access higher limits if needed. If you have higher or custom needs, [contact us to discuss individual situations.](https://discord.gg/blockscout)

* **JSON RPC**

  JSON RPC calls follow the same query structure as Etherscan. Blockscout supports most of the same calls. Replace the front part of the url from [https://api.etherscan.io/v2/api?chainid=](https://api.etherscan.io/v2/api?chainid=10)X to [**https://your-explorer-instance/api**](https://your-explorer-instance/api)

  * [Docs](/devs/apis/rpc)
  * [JSON RPC Postman collection example ](https://www.postman.com/blockscout/optimistic-etherscan-api)

<Accordion title="API Differences" icon="computer">
  ### **1. Account/Address Endpoints**\\

  `module=account`

  |                              | Blockscout | Etherscan | Purpose                                                 |
  | :--------------------------- | :--------- | :-------- | :------------------------------------------------------ |
  | `action=eth_get_balance`     | ✅          | ❌         | Mimics Ethereum JSON RPC's eth\_getBalance              |
  | `action=balance`             | ✅          | ✅         | Get Ether Balance for Single Address                    |
  | `action=balancemulti`        | ✅          | ✅         | Get Ether Balance for Multiple Addresses                |
  | `action=pendingtxlist`       | ✅          | ❌         | Get Pending Transactions by Address                     |
  | `action=txlist`              | ✅          | ✅         | Get Normal Transactions by Address                      |
  | `action=txlistinternal`      | ✅          | ✅         | Get Internal Transactions by Address                    |
  | `action=tokentx`             | ✅          | ✅         | Get ERC20 Token Transfers                               |
  | `action=tokennfttx`          | ✅          | ✅         | Get ERC721 Token Transfers                              |
  | `action=token1155tx`         | ✅          | ✅         | Get ERC1155 Token Transfers                             |
  | `action=token404tx`          | ✅          | ❌         | Get ERC-404 token transfer events by address            |
  | `action=tokenbalance`        | ✅          | ❌         | Get Token Balance for Address                           |
  | `action=tokenlist`           | ✅          | ❌         | Get list of tokens owned by address                     |
  | `action=getminedblocks`      | ✅          | ✅         | Get list of blocks mined by address                     |
  | `action=listaccounts`        | ✅          | ❌         | Get a list of accounts and their balances               |
  | `action=txsBeaconWithdrawal` | ❌          | ✅         | Get Beacon Chain Withdrawals by Address and Block Range |
  | `action=balancehistory`      | ❌          | ✅ (PRO)   | Get Historical Ether Balance for an Address By BlockNo  |

  ### **2. Contract Endpoints**

  ### `module=contract`

  |                                 | Blockscout | Etherscan | Purpose                                                         |
  | :------------------------------ | :--------- | :-------- | :-------------------------------------------------------------- |
  | `action=listcontracts`          | ✅          | ❌         | Get list of any deployed contract                               |
  | `action=getabi`                 | ✅          | ✅         | Get Contract ABI for verified contracts                         |
  | `action=getsourcecode`          | ✅          | ✅         | Get contract source code for a verified contract                |
  | `action=getcontractcreation`    | ✅          | ❌         | Get contract creator address hash and creation transaction hash |
  | `action=verify`                 | ✅          | ❌         | Verify Contract with Source Code                                |
  | `action=verifysourcecode`       | ✅          | ✅         | Verify Contract with JSON file                                  |
  | `action=checkverifystatus`      | ✅          | ✅         | Check Verification Status                                       |
  | `action=verifyproxycontract`    | ✅          | ✅         | Get Internal Transactions by Address                            |
  | `action=checkproxyverification` | ✅          | ✅         | Get ERC20 Token Transfers                                       |
  | `action=verify_via_scourcify`   | ✅          | ❌         | Verify a contract through                                       |
  | Sourcify                        |            |           |                                                                 |
  | `action=verify_vyper_contract`  | ✅          | ❌         | Verify a Vyper contract                                         |

  ### **3. Transaction Endpoints**

  ### `module=transaction`

  |                             | Blockscout | Etherscan | Purpose                                                       |
  | :-------------------------- | :--------- | :-------- | :------------------------------------------------------------ |
  | `action=gettxinfo`          | ✅          | ❌         | Get Transaction info including block number, sender, gas, +++ |
  | `action=gettxreceiptstatus` | ✅          | ✅         | Get Transaction Receipt Status                                |
  | `action=getstatus`          | ✅          | ✅         | Get Transaction Execution Status                              |

  ### **4. Block Endpoints**

  **module=block**

  |                                              | Blockscout | Etherscan | Purpose                                                        |
  | :------------------------------------------- | :--------- | :-------- | :------------------------------------------------------------- |
  | `action=getblockreward`                      | ✅          | ✅         | Get Block Rewards                                              |
  | `action=getblockcountdown`                   | ✅          | ✅         | Get Block Countdown                                            |
  | `action=getblocknobytime`                    | ✅          | ✅         | Get Block Number by Time                                       |
  | `action=eth_block_number`                    | ✅          | ❌         | Mimics Ethereum JSON RPC's eth\_blockNumber.                   |
  | <br /><br /><br />`action=dailyavgblocksize` | ❌          | ✅ (PRO)   | Get Daily Average Block Size                                   |
  | `action=dailyblkcount`                       | ❌          | ✅ (PRO)   | Get Daily Block Count and Rewards                              |
  | `action=dailyblockrewards`                   | ❌          | ✅ (PRO)   | Get Daily Block Rewards                                        |
  | `action=dailyavgblocktime`                   | ❌          | ✅ (PRO)   | Get Daily Average Time for A Block to be Included in the chain |
  | `action=dailyuncleblkcount`                  | ❌          | ✅ (PRO)   | Get Daily Uncle Block Count and Rewards                        |

  ### **5. Token Endpoints**

  ### `module=token`

  Note other endpoints contain token specific information including `module=stats` and `module=account`.

  |                         | Blockscout | Etherscan | Purpose                       |
  | :---------------------- | :--------- | :-------- | :---------------------------- |
  | action=getToken         | ✅          | ❌         | Get Token Information         |
  | action=getTokenHolders  | ✅          | ❌         | Get Token Holders             |
  | action=bridgedtokenlist | ✅          | ❌         | Get Bridged Tokens            |
  | action=tokenholderlist  | ❌          | ✅ (PRO)   | Get Token Holders             |
  | action=tokenholdercount | ❌          | ✅ (PRO)   | Number of ERC20 token holders |
  | action=tokeninfo        | ❌          | ✅ (PRO)   | Token project info            |

  ### **6. Logs/Events Endpoints**

  ### `module=logs`

  Both Etherscan and Blockscout use the getLogs endpoint which includes enhanced filtering capabilities

  * ✅ `action=getLogs` - Get Event Logs by Address/Topics/Block Range

  ### **7. Proxy/ETH RPC Endpoints**

  Etherscan uses the Proxy module `module=proxy` to retrieve standard Ethereum JSON-RPC methods.

  For Blockscout, send requests to `https://explorer.optimism.io/api/eth-rpc`

  The following methods are supported:

  * eth\_blockNumber
  * eth\_getBalance
  * eth\_getLogs
  * eth\_gasPrice
  * eth\_getTransactionByHash
  * eth\_getTransactionReceipt
  * eth\_chainId
  * eth\_maxPriorityFeePerGas
  * eth\_getTransactionCount
  * eth\_getCode
  * eth\_getStorageAt
  * eth\_estimateGas
  * eth\_getBlockByNumber
  * eth\_getBlockByHash
  * eth\_sendRawTransaction
  * eth\_call

  ### **8. Stats/Network Information**

  ### `module=stats`

  In addition to these stats, Blockscout provides general chain stats via the [REST API](/devs/apis/rest).

  |                       | Blockscout | Etherscan | Purpose                                                                                                                     |
  | :-------------------- | :--------- | :-------- | :-------------------------------------------------------------------------------------------------------------------------- |
  | tokensupply           | ✅          | ✅         | Get Token Information                                                                                                       |
  | ethsupplyexchange     | ✅          | ❌         | total supply in Wei from exchange                                                                                           |
  | ethsupply             | ✅          | ✅         | Get total supply in Wei from DB                                                                                             |
  | ethsupply2            | ❌          | ✅         | Get amount of Ether in circulation, ETH2 Staking rewards, EIP1559 burnt fees, and total withdrawn ETH from the beacon chain |
  | coinsupply            | ✅          | ❌         | Get total coin supply from DB minus burnt number                                                                            |
  | ethprice              | ✅          | ✅         | Get latest price of native coin in USD and BTC                                                                              |
  | coinprice             | ✅          | ❌         | Get latest price of native coin in USD and BTC in more general format                                                       |
  | totalfees             | ✅          | ❌         | Get total transaction fees in Wei paid by users to validators per day                                                       |
  | chainsize             | ❌          | ✅         | Get the size of the Ethereum blockchain, in bytes, over a date range.                                                       |
  | nodecount             | ❌          | ✅ (PRO)   | Get total number of discoverable Ethereum nodes                                                                             |
  | dailytxnfee           | ❌          | ✅ (PRO)   | Get Daily Network Transaction Fee                                                                                           |
  | dailynewaddress       | ❌          | ✅ (PRO)   | Get Daily New Address Count                                                                                                 |
  | dailynetutilization   | ❌          | ✅ (PRO)   | Get Daily Network Utilization                                                                                               |
  | dailyavghashrate      | ❌          | ✅ (PRO)   | Get Daily Average Network Hash Rate                                                                                         |
  | dailytx               | ❌          | ✅ (PRO)   | Get Daily Transaction Count                                                                                                 |
  | dailyavgnetdifficulty | ❌          | ✅ (PRO)   | Get Daily Average Network Difficulty                                                                                        |
  | ethdailyprice         | ❌          | ✅ (PRO)   | Get Ether Historical Price                                                                                                  |

  ### **9. Gas Tracking**

  **Etherscan Gas Tracker** (`module=gastracker`)

  * ✅ `action=gasoracle` - Get Gas Oracle
  * ✅ `action=gasestimate` - Get Gas Estimate

  **Blockscout**

  * ✅ Gas information integrated into transaction and block data
</Accordion>

* **REST API** availability/swagger

  Blockscout also provides a RESTful API which serves it’s frontend and is available for developers to use.

  * [Documentation and playground](/devs/apis/rest)
  * [Microservice and related swagger definitions](https://blockscout.github.io/swaggers/)
* A **GraphQL** playground is built into the explorer. Explore queries and schemas from the interface by visiting [**https://your-instance-here/graphiql**](https://your-instance-here/graphiql)

## Contract verification process

Blockscout offers advanced contract verification and interaction possibilities. Pre-existing contracts in various contexts are verified automatically (partial verification - which exposes the contract and methods) via the [Ethereum bytecode DB.](/about/features/ethereum-bytecode-database-microservice)

New contracts (Solidity, Vyper, Yul) can be verified via dev tools or directly in the Blockscout UI. \
<Icon icon="paper-plane-top" /> [Contract verification guide](/devs/verification/blockscout-smart-contract-verification-api)

<Check>
  Dev tools widely support the Blockscout explorer. For example:

  * Ethers.js: [https://docs.ethers.org/v6/api/providers/thirdparty/#providers-blockscout](https://docs.ethers.org/v6/api/providers/thirdparty/#providers-blockscout)
  * Hardhat: [https://www.npmjs.com/package/@ericxstone/hardhat-blockscout-verify](https://www.npmjs.com/package/@ericxstone/hardhat-blockscout-verify)
  * Foundry: [https://docs.blockscout.com/devs/verification/foundry-verification](https://docs.blockscout.com/devs/verification/foundry-verification)
  * Remix: [https://www.blog.blockscout.com/deploy-and-verify-your-contract-using-remix-and-blockscout/](https://www.blog.blockscout.com/deploy-and-verify-your-contract-using-remix-and-blockscout/)
</Check>

## My Account

Blockscout My Account lets you create watchlists, customize your explorer with private tags, create free API keys for extended use and more. <Icon icon="person" /> [My Account Guide](/using-blockscout/my-account)

# Making the most of your explorer experience

## Switching from Etherscan

If you are used to using Etherscan, it is easy to switch to Blockscout. Most information is presented in a similar manner and in similar places in the UI with parity in data presentation.

<Accordion title="Blockscout / Etherscan Feature Differences" icon="magnifying-glass-arrows-rotate">
  ## **Additional Blockscout feature set**

  [******An itemized list of over 60 features and views available on Blockscout that are not available on Optimistic Etherscan is available here.******](https://docs.google.com/spreadsheets/d/1HGw9bh5Iq3xBZlrnrwVOzD_0844zt7PPakkuxVsiS1g/edit?usp=sharing)

  * **DAppscout** DApp marketplace providing dapp discovery and interaction features.
  * **BENS in addition to ENS support, protocols can submit their subgraphs to be supported. Blockscout allows multiple protocols to co-exist within a single network.**
  * **Ads and banner control** - Ability to add and curate own ads/banners
  * **Public tagging - a central microservice allows tags enabled on mainnet to be shown on other chains. This is especially useful for malicious address display.**
  * **Vera and BytecodeDB Bytecode match works for verification info on multiple chains**
  * **Roadmap, research and rollup-specific features**
    * Rollup-specific feature support (e.g. Fault proofs)
    * DA support (e.g. [Celestia](https://github.com/blockscout/blockscout/pull/10199))

  ## **Additional Etherscan feature set (features not yet available on Blockscout)**

  * Page views not included in the Blockscout UI

    * [NFT Latest Transfers](https://optimistic.etherscan.io/nft-transfers)
    * [NFT Latest Mints](https://optimistic.etherscan.io/nft-latest-mints)

    Developer tools not included in Blockscout

    * [EVM bytecode decompiler (experimental)](https://optimistic.etherscan.io/bytecode-decompiler)
    * [Contract > Similar contracts](https://optimistic.etherscan.io/find-similar-contracts)
    * [Contract > Diff checker](https://optimistic.etherscan.io/contractdiffchecker)
    * [Contract > Bytecode to Opcode Disassembler](https://optimistic.etherscan.io/opcode-tool)
    * [Vyper Online Compiler](https://optimistic.etherscan.io/vyper)
    * [AI Code reader](https://optimistic.etherscan.io/code-reader)

    Tools and services not included in Blockscout

    Blockscout does not include some add-on tooling such as the

    [input data converter](https://etherscan.io/inputdatadecoder), [unit converter](https://etherscan.io/unitconverter), [token approvals](https://etherscan.io/tokenapprovalchecker) and [verified signatures](https://etherscan.io/verifiedSignatures). These are readily available through 3rd party applications and/or currently not considered as high-priority features.
</Accordion>

## Using Dappscout

Dappscout is a decentralized application marketplace built into Blockscout. It features a list of dapps available on Optimism.  <Icon icon="store" /> [Dappscout Guide](/using-blockscout/blockscout-apps)


# Running Blockscout
Source: https://docs.blockscout.com/get-started/running-blockscout

Hosting, ENVs and other info

<Tip>
  Blockscout also provides several hosting options for projects who do not want to run their own explorers.

  * [Autoscout](/using-blockscout/autoscout) allows you to setup an explorer in minutes. Hosted on Blockscout's cloud infra.
  * [Explorer as a Service](https://eaas.blockscout.com/) provides an SLA, optimized on prem hosting, and explorer customization.
</Tip>

Blockscout open-source software can be forked and used by any project to quickly setup an full-featured explorer environment. Be sure to [check the requirements](/setup/requirements) and tune your environment before deploying an explorer.

## **Deployment Options**

Common deployment methods below, there are additional deployment methods as well described in the [deployment ](/setup/deployment)section.

* [Docker Deployment](/setup/deployment/docker-compose-deployment)
* [Kubernetes Deployment](/setup/deployment/kubernetes-deployment)
* [Manual Deployment](/setup/deployment/manual-deployment-guide)

## **Configuration**

* [ENV Variables](/setup/env-variables)
  * [Backend](/setup/env-variables/backend-env-variables)
  * [Frontend](/setup/env-variables/frontend-common-envs)
  * [L2s and chain specific variables](/setup/env-variables/backend-envs-chain-specific)
* [Microservices](/setup/microservices)
  * Includes many plugin services written in Rust and available via the [Microservices RS repository](https://github.com/blockscout/blockscout-rs).
* [Configs](/setup/configuration-options)
  * Additional available configurations beyond ENV updates.
* [Architecture](/setup/information-and-settings)
  * Describes the Blockscout architecture including an [indexer architecture overview.](/setup/information-and-settings/indexer-architecture-overview)


# Using an Explorer
Source: https://docs.blockscout.com/get-started/using-an-explorer

Retrieving and interacting with blockchain data

An explorer acts as a comprehensive frontend to the blockchain backend. It indexes, fetches, and organizes onchain data along with relevant metadata regarding transactions, blocks, tokens and addresses. Explorers provide all of this information in an organised, human readable format.

Included in the data that explorers provide is smart contract information, the code and methods as well as ways to interaction capabilities. Contract transparency and interaction is only available once a contract is verified.

Direct access to blockchain data is available via the explorer UI as well as through various API endpoints. Blockscout provides both JSON RPC and REST APIs for projects who need direct access to data via API calls.

* **Explorer Basics**
  * Searching [blocks](/using-blockscout/overviews/blocks)
  * [Transaction ](/using-blockscout/overviews/transaction-fields)details
  * [Address ](/using-blockscout/overviews/address-page)information
  * [Contract](/devs/verification/interacting-with-smart-contracts) interactions
  * [Menu](/using-blockscout/overviews/top-menu) and [Glossary](/using-blockscout/overviews/glossary-of-terms)
* **Account Features**
  * [My Account setup](/using-blockscout/my-account) and features
  * [API keys ](/using-blockscout/my-account/api-keys)for personal use (an API key is not needed, but can be freely added for additional limits)
  * [Watchlists](/using-blockscout/my-account/watchlist) and notifications
* **Scout Apps**
  * [Swapscout ](/using-blockscout/swapscout)cross-chain swaps/bridging
  * [Revokescout](/using-blockscout/revokescout) revoke token approvals
  * [Dappscout](/using-blockscout/revokescout) apps marketplace
  * [Autoscout](/using-blockscout/autoscout) self-service explorer launchpad


# GitHub Repo
Source: https://docs.blockscout.com/github-repo





# What is WaaS
Source: https://docs.blockscout.com/guides/developer-support/waas

Blockscout's wallet as a service provides instant access to a robust global ecosystem wallet

<Tip>
  [Contact the Blockscout team](https://eaas.blockscout.com/?utm_medium=header#contact) if you are ready to integrate a global wallet and start onboarding new users today.
</Tip>

## What is WaaS?

Blockscout's WaaS offers ready-made wallet infrastructure for supported blockchains.

* Developers can integrate directly into their applications [via the SDK](https://www.npmjs.com/package/@blockscout/rootstock-global-wallet), providing a full-featured wallet which can include a swap functionality, a fiat on/off ramp, and more.
* Wallets are created with familiar methods like email or passkey login. WaaS makes wallet creation and usage as easy as creating any standard online account.
* Users can immediately begin using the wallet. Account abstraction allows for multi-token fee payment, and gas sponsorship capabilities provide no-cost transaction fees when activated.

## WaaS benefits

**1) Stronger onboarding**\
New users can onboard instantly through email, social login, passkeys, or a classic wallet, creating a fast, frictionless experience.

**2) Seamless experience across the ecosystem**\
Once logged in, the same embedded smart wallet can be used across all participating applications, improving retention and promoting activity. Integrated features like wallet connect provide instant connection to all web3 applications.

**3) Better developer environment**\
Developers can integrate the ecosystem wallet SDK, shortening build time and providing consistent UX across the chain.

**4) On ramp and gas sponsorship**\
On and off-ramp features can be easily implemented, offering a full fiat-to-crypto experience. Gas sponsorship options allow for instant usage.

##


# Integration Guide
Source: https://docs.blockscout.com/guides/developer-support/wallet-as-a-service-waas/integration-guide

Integrate the global wallet SDK into your app on a supported chain

<Info>
  To learn about integrating with additional TypeScript frameworks, see our [wallet example repository.](https://github.com/blockscout/global-wallet-examples)
</Info>

<Note>
  Examples use the **Rootstock ecosystem** where our wallet is currently integrated. If you are interested in wallet support for your ecosystem, [Contact the Blockscout team](https://eaas.blockscout.com/?utm_medium=header#contact) today.
</Note>

## Resources

* WaaS Developer SDK npm package: [https://www.npmjs.com/package/@blockscout/rootstock-global-wallet](https://www.npmjs.com/package/@blockscout/rootstock-global-wallet)
* SDK integration use case examples: [https://github.com/blockscout/global-wallet-examples](https://github.com/blockscout/global-wallet-examples)
* Blockscout WaaS explainer: [https://www.blog.blockscout.com/what-is-wallet-as-a-service-waas-simplifying-web3-onboarding-ecosystem-approach](https://www.blog.blockscout.com/what-is-wallet-as-a-service-waas-simplifying-web3-onboarding-ecosystem-approach/)

## Installation

1. Install the global wallet SDK

```shellscript theme={null}
npm install @blockscout/rootstock-global-wallet
```

2. Import  into your project

```shellscript theme={null}
import "@blockscout/rootstock-global-wallet/ethereum";
```

The wallet is now available for usage!

<img alt="Image" />

## Gas Sponsorship / Paymasters

Gas sponsorship  is available through provider interagrations. In this example we use [**Gelato**](https://gelato.cloud/); various providers such as [Pimlico](https://docs.pimlico.io/references/paymaster), [ZeroDev](https://docs.zerodev.app/sdk/infra/intro) or [Biconomy](https://legacy-docs.biconomy.io/Paymaster/integration) can also be used.

## Get started with Gelato

1. Request API Key

To enable the paymaster for the global wallet, you need to have an API key first. To get an API key, [please fill out the form](https://airtable.com/app6JasG7IwPqc0wV/pagJJIIMeuVH7gbPj/form) and we will send you one.

2. Install Gelato and dependencies

```shellscript wrap theme={null}
npm install @gelatonetwork/smartwallet @dynamic-labs/sdk-react-core @dynamic-labs/ethereum @dynamic-labs/wagmi-connector @tanstack/react-query wagmi viem
```

3. Create `.env` variable and add API key

```shellscript theme={null}
NEXT_PUBLIC_GELATO_API_KEY=your_gelato_api_key
```

4. Create a Gelato Smart Wallet Client for sponsored operations

```javascript theme={null}
const App = () => {
  const sendTransaction = async () => {
    const { primaryWallet, handleLogOut } = useDynamicContext();

    if (!primaryWallet || !isEthereumWallet(primaryWallet)) {
      return;
    }

    const connector = primaryWallet.connector;

    if (!connector || !isDynamicWaasConnector(connector)) {
      return;
    }

    if (chain.id) {
      await primaryWallet.switchNetwork(chain.id);
    }

    const client = await primaryWallet.getWalletClient();

    client.account.signAuthorization = async (parameters) => {
      const preparedAuthorization = await prepareAuthorization(
        client,
        parameters
      );
      const signedAuthorization = await connector.signAuthorization(
        preparedAuthorization
      );

      return {
        address: preparedAuthorization.address,
        chainId: preparedAuthorization.chainId,
        nonce: preparedAuthorization.nonce,
        r: signedAuthorization.r,
        s: signedAuthorization.s,
        v: signedAuthorization.v,
        yParity: signedAuthorization.yParity,
      } as SignAuthorizationReturnType;
    };

    const smartWalletClient = await createGelatoSmartWalletClient(client, {
      apiKey: process.env.NEXT_PUBLIC_GELATO_API_KEY,
      scw: { type: "gelato" }, // use gelato, kernel, safe, or custom
    });
  };
  return (
    <div>
      <button onClick={sendTransaction}>Send Transaction</button>
    </div>
  );
};
```

5. Execute transactions using different payment methods

   a. Sponsored transactions

   ```javascript theme={null}
   const results = await smartWalletClient?.execute({
     payment: sponsored(),
     calls: [
       {
         to: "0xa8851f5f279eD47a292f09CA2b6D40736a51788E",
         data: "0xd09de08a",
         value: 0n,
       },
     ],
   });
   ```

   b. ERC-20 tokens (example uses USDC on Base Sepolia)

   ```javascript theme={null}
   import { erc20 } from "@gelatonetwork/smartwallet";

   const token = "0x036CbD53842c5426634e7929541eC2318f3dCF7e"; // USDC (Base Sepolia)

   const results = await smartWalletClient?.execute({
     payment: erc20(token),
     calls: [
       {
         to: "0xa8851f5f279eD47a292f09CA2b6D40736a51788E",
         data: "0xd09de08a",
         value: 0n,
       },
     ],
   });
   ```

   c. Native tokens (ie RBTC)

   ```javascript theme={null}
   import { native } from "@gelatonetwork/smartwallet";

   const results = await smartWalletClient?.execute({
     payment: native(),
     calls: [
       {
         to: "0xa8851f5f279eD47a292f09CA2b6D40736a51788E",
         data: "0xd09de08a",
         value: 0n,
       },
     ],
   });
   ```

### More details

See below for more info on gas sponsoring with Gelato

1. [https://github.com/gelatodigital/smartwallet/tree/master/plugins/react/dynamic](https://github.com/gelatodigital/smartwallet/tree/master/plugins/react/dynamic)
2. [https://docs.gelato.cloud/smart-wallet-sdk/integration-guides/dynamic](https://docs.gelato.cloud/smart-wallet-sdk/integration-guides/dynamic)


# Current Integrations
Source: https://docs.blockscout.com/guides/developer-support/wallet-as-a-service-waas/integrations



<Tip>
  [Contact the Blockscout team](https://eaas.blockscout.com/?utm_medium=header#contact) if you are ready to integrate a global wallet and start onboarding new users today.
</Tip>

## Current Integrations

### Rootstock

Rootstock is the first live WaaS integration, made possible by a [grant from the Rootstock Collective DAO.](https://gov.rootstockcollective.xyz/t/2512-grant-1-rootstock-global-wallet-by-blockscout/679https://gov.rootstockcollective.xyz/t/2512-grant-1-rootstock-global-wallet-by-blockscout/679) The wallet provides coverage for the entire ecosystem with a simple login, swap, onramp, and account abstraction features.

* Rootstock Global Wallet  [https://rootstock-wallet.blockscout.com/](https://rootstock-wallet.blockscout.com/)

### Polygon

A standalone wallet is available for the Polygon ecosystem. Swap, deposit and send tokens seamlessly.

* Polygon Global wallet [https://polygon-wallet.blockscout.com/](https://polygon-wallet.blockscout.com/)


# Blockscout Docs
Source: https://docs.blockscout.com/index

Blockscout is a universal, open-source blockchain explorer for inspecting, analyzing, and interacting with EVM-based chains. Blockscout supports over 1000 L1, L2 and L3 EVM-based chains, optimistic rollups, and ZK rollups. 

<CardGroup>
  <Card title="New to Blockscout?" icon="sparkles" href="get-started/new-to-blockscout">
    Learn about key features and supported chains
  </Card>

  <Card title="Using an Explorer" icon="searchengin" href="get-started/using-an-explorer">
    Quickstart for blockchain explorer users
  </Card>

  <Card title="Data and APIs" icon="database" href="get-started/integrating-data">
    Get started with APIs, SDK and more
  </Card>

  <Card title="Running Blockscout" icon="person-running" href="get-started/running-blockscout">
    Get your self hosted instance up-and-running
  </Card>

  <Card title="Migration Guide" icon="bird" href="get-started/migration-guide">
    Switch to Blockscout from another explorer like Etherscan
  </Card>
</CardGroup>

## Explorer Hosting Options

<Tip>
  * [Explorer as a Service](https://eaas.blockscout.com/#explorer-as-a-service) for enterprise and production grade hosting
  * [Autoscout](https://deploy.blockscout.com/) self-service launchpad for instant explorer deployment
</Tip>

<img alt="Blockscout Optimism Block Explorer" />


# Contributing to Blockscout
Source: https://docs.blockscout.com/resources/contributing-to-blockscout

How to contribute to Blockscout and collaborate with the community.

We welcome community contributions and collaboration! To get started, please visit our github:

<Card title="GitHub - blockscout/blockscout: Blockchain explorer for Ethereum based network and a tool for inspecting and analyzing EVM based blockchains." href="https://github.com/poanetwork/blockscout">
  GitHub
</Card>


# Media Kit
Source: https://docs.blockscout.com/resources/media-kit

Branding and Logos

## Blockscout Primary Branding Kit

<Frame>
  <img alt="" />
</Frame>

<Card title="Blockscout_media_kit.zip" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2FgRBRganHDXgfb18wttgj%2FBlockscout_media_kit.zip?alt=media&token=5669e670-cc83-4157-b6cf-a21c2b5bc322">
  archive
</Card>

## Blockscout Merits Program

<Frame>
  <img alt="" />
</Frame>

<Card title="Blockscout_Merits_logos.zip" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2Fuz9d6bjUSPReKKvPx5Zk%2FBlockscout_Merits_logos.zip?alt=media&token=4e7e6155-0ce7-4479-92b2-af3945a4dd6d">
  archive
</Card>

## Autoscout Self-Service Launchpad

<img alt="Autoscout Media Kit Pn" />

<Card title="Autoscout_media_kit.zip" href="https://blockscout-icons.s3.us-east-1.amazonaws.com/docs-files/Autoscout_logos.zip">
  archive
</Card>


# EaaS: Hosting with Blockscout
Source: https://docs.blockscout.com/resources/premium-features

Explorer as a Service offerings from Blockscout

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. **[Get Started Now](/using-blockscout/autoscout) and have your explorer up-and-running in minutes.**
</Tip>

Hosted instances receive support and updates not available to non-hosted instances. If you have questions about integrating services or current premium integrations please ask in [Discord.](https://discord.gg/XmNatGKbPS)

🚄 **Hosting on blockscout.com**: Self-hosting can be difficult, often requiring a dev-ops team to make critical in-house updates and/or customizations. A Blockscout-hosted chain not only gives projects access to expert, dedicated technical support, it also greatly increases project visibility and provides access to the premium feature set.

👩🏻 **Priority Updates:** The Ethereum mainnet BlockScout instance is updated regularly with the latest functionality. Premium hosted versions of BlockScout receive these same updates and patches. This includes community requested features, UI enhancements, protocol updates, fixes, and any other additions.

👨💻 **Priority Support & SLA:** Premium customers receive personalized, priority assistance from the BlockScout support team. The BlockScout team responds to issues, requests, and bug reports from premium customers first and responds to your team's requests through a dedicated support channel.

## Hosting your chain on [BlockScout.com](http://blockscout.com/)

Chains hosted on [BlockScout.com](http://blockscout.com/) are **highly visible to the users who visit the website every day**. In addition, chains hosted on [BlockScout.com](http://blockscout.com/) receive **dedicated technical assistance.**

**Benefits include:**

* A branded UI theme with the latest version of Blockscout UI.

* Automatic updates to BlockScout stable versions.

* Customization for specific chain parameters such as market cap, validator info and others as needed.

* Dedicated support from BlockScout core team.

If you would like explore hosting options with [BlockScout.com](http://blockscout.com/), please [contact us](https://discord.com/invite/ZUnrZTK). We will set up a call to discuss your chain's unique needs and begin taking the next steps towards integration.


# Release Notes
Source: https://docs.blockscout.com/resources/release-notes



Backend releases and notes: [https://github.com/blockscout/blockscout/releases](https://github.com/blockscout/blockscout/releases?page=1)

Frontend releases and notes: [https://github.com/blockscout/frontend/releases](https://github.com/blockscout/frontend/releases)


# V5.0.0: 1/11/23
Source: https://docs.blockscout.com/resources/release-notes/v5-0-0-1-11-23

Release notes for Blockscout version 5.0.0 (January 11, 2023).

<Info>
  All backend release notes are now available on github at [https://github.com/blockscout/blockscout/releases](https://github.com/blockscout/blockscout/releases)
</Info>

## Highlights

This update brings in many new features to support customizability within the explorer. My account functions, the ability to add tags, and smart contract verification improvements, including yul verification via the Rust microservice.

## New Features List

* [#6092](https://github.com/blockscout/blockscout/pull/6092) - Blockscout Account functionality

* [#6324](https://github.com/blockscout/blockscout/pull/6324) - Add verified contracts list page

* [#6316](https://github.com/blockscout/blockscout/pull/6316) - Public tags functionality

* [#6444](https://github.com/blockscout/blockscout/pull/6444) - Add support for yul verification via rust microservice

* [#6073](https://github.com/blockscout/blockscout/pull/6073) - Add vyper support for rust verifier microservice integration

* [#6401](https://github.com/blockscout/blockscout/pull/6401) - Add Sol2Uml contract visualization

* [#6583](https://github.com/blockscout/blockscout/pull/6583), [#6687](https://github.com/blockscout/blockscout/pull/6687) - Missing ranges collector

* [#6574](https://github.com/blockscout/blockscout/pull/6574), [#6601](https://github.com/blockscout/blockscout/pull/6601) - Allow and manage insecure HTTP connection to the archive node

* [#6433](https://github.com/blockscout/blockscout/pull/6433), [#6698](https://github.com/blockscout/blockscout/pull/6698) - Update error pages

* [#6544](https://github.com/blockscout/blockscout/pull/6544) - API improvements

* [#5561](https://github.com/blockscout/blockscout/pull/5561), [#6523](https://github.com/blockscout/blockscout/pull/6523), [#6549](https://github.com/blockscout/blockscout/pull/6549) - Improve working with contracts implementations

* [#6481](https://github.com/blockscout/blockscout/pull/6481) - Smart contract verification improvements

* [#6440](https://github.com/blockscout/blockscout/pull/6440) - Add support for base64 encoded NFT metadata

* [#6407](https://github.com/blockscout/blockscout/pull/6407) - Indexed ratio for int txs fetching stage

* [#6379](https://github.com/blockscout/blockscout/pull/6379), [#6429](https://github.com/blockscout/blockscout/pull/6429), [#6642](https://github.com/blockscout/blockscout/pull/6642), [#6677](https://github.com/blockscout/blockscout/pull/6677) - API v2 for frontend

* [#6351](https://github.com/blockscout/blockscout/pull/6351) - Enable forum link env var

* [#6196](https://github.com/blockscout/blockscout/pull/6196) - INDEXER\_CATCHUP\_BLOCKS\_BATCH\_SIZE and INDEXER\_CATCHUP\_BLOCKS\_CONCURRENCY env variables

* [#6187](https://github.com/blockscout/blockscout/pull/6187) - Filter by created time of verified contracts in listcontracts API endpoint

* [#6111](https://github.com/blockscout/blockscout/pull/6111) - Add Prometheus metrics to indexer

* [#6168](https://github.com/blockscout/blockscout/pull/6168) - Token instance fetcher checks instance owner and updates current token balance

* [#6209](https://github.com/blockscout/blockscout/pull/6209) - Add metrics for block import stages, runners, steps

* [#6257](https://github.com/blockscout/blockscout/pull/6257), [#6276](https://github.com/blockscout/blockscout/pull/6276) - DISABLE\_TOKEN\_INSTANCE\_FETCHER env variable

* [#6391](https://github.com/blockscout/blockscout/pull/6391), [#6427](https://github.com/blockscout/blockscout/pull/6427) - TokenTransfer token\_id -> token\_ids migration

* [#6443](https://github.com/blockscout/blockscout/pull/6443) - Drop internal transactions order index

* [#6450](https://github.com/blockscout/blockscout/pull/6450) - INDEXER\_INTERNAL\_TRANSACTIONS\_BATCH\_SIZE and INDEXER\_INTERNAL\_TRANSACTIONS\_CONCURRENCY env variables

* [#6454](https://github.com/blockscout/blockscout/pull/6454) - INDEXER\_RECEIPTS\_BATCH\_SIZE, INDEXER\_RECEIPTS\_CONCURRENCY, INDEXER\_COIN\_BALANCES\_BATCH\_SIZE, INDEXER\_COIN\_BALANCES\_CONCURRENCY env variables

* [#6476](https://github.com/blockscout/blockscout/pull/6476), [#6484](https://github.com/blockscout/blockscout/pull/6484) - Update token balances indexes

* [#6510](https://github.com/blockscout/blockscout/pull/6510) - Set consensus: false for blocks on int transaction foreign\_key\_violation

* [#6565](https://github.com/blockscout/blockscout/pull/6565) - Set restart: :permanent for permanent fetchers

* [#6568](https://github.com/blockscout/blockscout/pull/6568) - Drop unfetched\_token\_balances index

* [#6647](https://github.com/blockscout/blockscout/pull/6647) - Pending block operations update

* [#6542](https://github.com/blockscout/blockscout/pull/6542) - Init mixpanel and amplitude analytics


# V5.1.0: 2/13/23
Source: https://docs.blockscout.com/resources/release-notes/v5-1-0-2-13-23

Release notes for Blockscout version 5.1.0 (February 13, 2023).

<Info>
  All backend release notes are now available on github at [https://github.com/blockscout/blockscout/releases](https://github.com/blockscout/blockscout/releases)
</Info>

## Highlights

Improvements to the smart contract verifier service and additions the v2 API increase speed and usability

## New Features List

* [#6871](https://github.com/blockscout/blockscout/pull/6871) - Integrate new smart contract verifier version

* [#6838](https://github.com/blockscout/blockscout/pull/6838) - Disable dark mode env var

* [#6843](https://github.com/blockscout/blockscout/pull/6843) - Add env variable to hide Add to MM button

* [#6744](https://github.com/blockscout/blockscout/pull/6744) - API v2: smart contracts verification

* [#6763](https://github.com/blockscout/blockscout/pull/6763) - Permanent UI dark mode

* [#6721](https://github.com/blockscout/blockscout/pull/6721) - Implement fetching internal transactions from callTracer

* [#6541](https://github.com/blockscout/blockscout/pull/6541) - Integrate sig provider

* [#6712](https://github.com/blockscout/blockscout/pull/6712), [#6798](https://github.com/blockscout/blockscout/pull/6798) - API v2 update

* [#6582](https://github.com/blockscout/blockscout/pull/6582) - Transaction actions indexer

* [#6863](https://github.com/blockscout/blockscout/pull/6863) - Move OnDemand fetchers from indexer supervisor


# V5.2.0: 6/20/23
Source: https://docs.blockscout.com/resources/release-notes/v5-2-0-6-20-23

Release notes for Blockscout version 5.2.0 (June 20, 2023).

<Info>
  All backend release notes are now available on github at [https://github.com/blockscout/blockscout/releases](https://github.com/blockscout/blockscout/releases)
</Info>

## Highlights

This update focused on optimizations related to search speed and overall explorer performance. Transactions are now populating much faster on the page and the UX is improved to provide relevant search details quickly.

There was also a focus on supporting zkEVM and Polygon Edge networks, providing needed support for Polygon associated chains.

CSV exports were also improved with filters, making export data more usable for a variety of applications.

## New Features List

* [#7502](https://github.com/blockscout/blockscout/pull/7502) - Improve performance of some methods, endpoints and SQL queries

* [#7665](https://github.com/blockscout/blockscout/pull/7665) - Add standard-json vyper verification

* [#7685](https://github.com/blockscout/blockscout/pull/7685) - Add yul filter and "language" field for smart contracts

* [#7653](https://github.com/blockscout/blockscout/pull/7653) - Add support for DEPOSIT and WITHDRAW token transfer event in older contracts

* [#7628](https://github.com/blockscout/blockscout/pull/7628) - Support partially verified property from verifier MS; Add property to track contracts automatically verified via eth-bytecode-db

* [#7603](https://github.com/blockscout/blockscout/pull/7603) - Add Polygon Edge and optimism genesis files support

* [#7585](https://github.com/blockscout/blockscout/pull/7585) - Store and display native coin market cap from the DB

* [#7513](https://github.com/blockscout/blockscout/pull/7513) - Add Polygon Edge support

* [#7532](https://github.com/blockscout/blockscout/pull/7532) - Handle empty id in json rpc responses

* [#7544](https://github.com/blockscout/blockscout/pull/7544) - Add ERC-1155 signatures to uncataloged\_token\_transfer\_block\_numbers

* [#7363](https://github.com/blockscout/blockscout/pull/7363) - CSV export filters

* [#7697](https://github.com/blockscout/blockscout/pull/7697) - Limit fetchers init tasks


# V5.3.0: 10/23/23
Source: https://docs.blockscout.com/resources/release-notes/v5-3-0-10-23-23

Release notes for Blockscout version 5.3.0 (October 23, 2023).

<Info>
  All backend release notes are now available on github at [https://github.com/blockscout/blockscout/releases](https://github.com/blockscout/blockscout/releases)
</Info>

## Highlights

* `CHAIN_TYPE` env variable which can provide different logic for fetchers, API, views, DB schema extensions are applied to the explorer. Additional values will be supported in upcoming releases - currently supported values are:

  * `ethereum` - default value

  * `polygon_edge` - chains based on Polygon Edge nodes

  * `rsk` - for Rootstock (rskj node)

* TVL display is live with the DefiLlama API integration

* DB schema update which will support additional NFT views on owner addresses. The view is still in development, scheme update was required first.

* `IPFS_GATEWAY_URL` endpoint allows projects to connect Blockscout to their own IPFS gateway for fetching token metadata.

* Many additional improvements and fixes on the indexer side and API.

## New Features List

* [#8512](https://github.com/blockscout/blockscout/pull/8512) - Add caching and improve `/tabs-counters` performance

* [#8472](https://github.com/blockscout/blockscout/pull/8472) - Integrate `/api/v2/bytecodes/sources:search-all` of `eth_bytecode_db`

* [#8589](https://github.com/blockscout/blockscout/pull/8589) - DefiLlama TVL source

* [#8583](https://github.com/blockscout/blockscout/pull/8583) - Add stats widget for rootstock

* [#8542](https://github.com/blockscout/blockscout/pull/8542) - Add tracing for rootstock

* [#8561](https://github.com/blockscout/blockscout/pull/8561), [#8564](https://github.com/blockscout/blockscout/pull/8564) - Get historical market cap data from CoinGecko

* [#8543](https://github.com/blockscout/blockscout/pull/8543) - Fix polygon tracer

* [#8386](https://github.com/blockscout/blockscout/pull/8386) - Add `owner_address_hash` to the `token_instances`

* [#8530](https://github.com/blockscout/blockscout/pull/8530) - Add `block_type` to search results

* [#8180](https://github.com/blockscout/blockscout/pull/8180) - Deposits and Withdrawals for Polygon Edge

* [#7996](https://github.com/blockscout/blockscout/pull/7996) - Add CoinBalance fetcher init query limit

* [#8658](https://github.com/blockscout/blockscout/pull/8658) - Remove block consensus on import fail

* [#8575](https://github.com/blockscout/blockscout/pull/8575) - Filter token transfers on coin balances updates


# Security Program
Source: https://docs.blockscout.com/resources/security-program

Responsible security vulnerability disclosure

Ensuring the safety of our open-source explorer platform is a top priority, and we greatly appreciate the **crucial role security researchers play in contributing to open source**. Should you identify a possible security vulnerability within our platform, we invite you to share your findings.

## How to report a security vulnerability

Send us an email with the information below. We ask that you please keep your findings confidential during the reporting process. We will get back to you if we determine the issue is a vulnerability and discuss potential next steps and compensation.  We may patch the vulnerability prior to our response to you, and we will asses the risk level on a case-by-case basis.

<Warning>
  We will only get back to you if we determine the issue is a real security risk. Please do not submit spam reports as this takes away valuable time from our open-source development team.
</Warning>

1. **Description of the bug/vulnerability**

   Clearly describe the vulnerability you've discovered.
2. **Steps to reproduce** \
   Outline the steps needed to replicate the vulnerability.
3. **Impact analysis**\
   Assess the potential impact of the vulnerability on users, developers, and the organization.
4. **Code fix (optional)**\
   If possible and appropriate, you may include a suggested code fix for the vulnerability.
5. **Type of vulnerability**\
   Choose a label that best fits the category of the bug for classification purposes.
6. **Additional Context**\
   Provide any additional information that could help in understanding and resolving the issue.
7. **Email your report**\
   Email your report to [security@blockscout.com](mailto:%22security%40blockscout.com%22%20%3Csecurity%40blockscout.com%3E)

<Info>
  Information is also available on the [SECURITY page of our Github Repo](https://github.com/blockscout/.github/blob/7a136f9c6091bf8b03195224f8abe56305ebb795/SECURITY.md?plain=1#L3).
</Info>

### Security Considerations

The following items are considered high priority:

* Business logic bugs or problems
* Remote code execution (RCE)
* Database vulnerability, SQLi
* File inclusions (Local & Remote)
* Access Control Issues (IDOR, Privilege Escalation, etc)
* Sensitive information leaks
* Server-Side Request Forgery (SSRF)
* Other vulnerability with a clear potential loss

### **Out of Scope Items**

Unless presenting a serious business risk (at our discretion), the following are typically not considered security issues.

* Minor visual bugs, spelling errors, etc.
* Social engineering tactics (e.g., phishing)
* Issues in applications or systems not listed in the scope
* UI/UX bugs, data entry errors, and typos
* Network level Denial of Service (DoS/DDoS) vulnerabilities
* Certificate/TLS/SSL issues
* DNS configuration problems
* Server configuration issues (open ports, TLS configurations, etc.)
* Spam or social engineering techniques
* Security flaws in third-party apps or services
* Non-impactful XSS exploits
* CSRF-XSS issues related to login/logout
* Issues related to https/ssl or server-info disclosure
* Mixed Content Scripts
* Brute Force attacks
* General best practices concerns
* Recently disclosed 0day vulnerabilities
* Username/email enumeration via error messages
* Missing HTTP security headers
* Weak password policies
* HTML injection

## 🐐 Security  GOATs

<Check>
  Thank you for your help keeping vital public infrastructure like block explorers safe and secure!
</Check>

* blackgrease: [https://github.com/blackgrease](https://github.com/blackgrease)


# Celestia Node / Indexer
Source: https://docs.blockscout.com/setup/celestia-node-indexer



<Note>
  More info on the Blockscout + Celestia integration is available in this blog post: [https://www.blog.blockscout.com/celestia-superhighway-supporting-high-data-availability-on-blockscout/](https://www.blog.blockscout.com/celestia-superhighway-supporting-high-data-availability-on-blockscout/)
</Note>

## How to run a Celestia light node with a Celestia blobs indexer

We'll use Docker Compose to run everything we need: Celestia Light node, Blobs indexer, and Postgres DB for it.

<Tip>
  Please note that the Celestia node requires linux/amd64 or linux/arm64 OS
</Tip>

### Setup

The `docker-compose.yml` contains the following:

```yml theme={null}
services:
  celestia-light-node:
    image: ghcr.io/celestiaorg/celestia-node:v0.21.8-mocha
    container_name: celestia-light-node
    restart: always
    env_file:
      - .env
    command: ["celestia", "light", "start", "--core.ip", "${RPC_URL}", "--core.port", "9090", "--p2p.network", "${P2P_NETWORK}", "--rpc.addr", "0.0.0.0", "--rpc.skip-auth", "--gateway", "--gateway.addr", "0.0.0.0"]
    ports:
      - 26658:26658
      - 9090:9090
    volumes:
      - /data/celestia:/home/celestia

  database:
    image: postgres:15
    container_name: 'da-indexer-postgres'
    restart: always
    environment:
      POSTGRES_PASSWORD: 'our_password'
      POSTGRES_USER: 'postgres'
      POSTGRES_HOST_AUTH_METHOD: 'trust'
    ports:
      - 5432:5432
    volumes:
      - /data/postgres:/var/lib/postgresql/data

  da-indexer:
    image: ghcr.io/blockscout/da-indexer:v1.1.0
    container_name: 'da-indexer'
    restart: always
    depends_on:
      - database
    ports:
      - "8050:8050"
      - "8051:8051"
    env_file:
      - indexer.env
```

Make sure to replace `our_password` for the DB with your password.

This yml requires having two env files in the same directory:

**1)** `.env` for configuring the light node:

```
P2P_NETWORK=mocha
RPC_URL=celestia-mocha-archive-rpc.mzonder.com
# P2P_NETWORK=celestia
# RPC_URL=celestia-rpc.brightlystake.com
```

Uncomment and use the last two lines when you need Celestia Mainnet instead of Celestia Mocha. \
\
The lists of Celestia RPC nodes can be found at:

* [https://docs.celestia.org/how-to-guides/mocha-testnet#production-rpc-endpoints](https://docs.celestia.org/how-to-guides/mocha-testnet#production-rpc-endpoints)
* [https://docs.celestia.org/how-to-guides/mainnet#production-rpc-endpoints](https://docs.celestia.org/how-to-guides/mainnet#production-rpc-endpoints)

**2)** `indexer.env` for configuring the blobs indexer:

```
DA_INDEXER__INDEXER__DA__CELESTIA__RPC__URL="http://celestia-light-node:26658"
DA_INDEXER__INDEXER__DA__CELESTIA__SAVE_BATCH_SIZE=1000
DA_INDEXER__INDEXER__CONCURRENCY=15
DA_INDEXER__DATABASE__CONNECT__URL=postgres://postgres:our_password@database:5432/blockscout
DA_INDEXER__DATABASE__CREATE_DATABASE="true"
DA_INDEXER__DATABASE__RUN_MIGRATIONS="true"
```

Here you only need to replace `our_password` with the DB password defined in the `docker-compose.yml`.

### Usage

* To start the services, run `docker compose up -d`.
* To see the last indexer logs, run `docker logs -n 100 da-indexer`.
* To see the last node logs, run `docker logs -n 100 celestia-light-node`.

After services are started, the indexer API is available here: [http://example.com:8050/api/v1/celestia/blob](http://example.com:8050/api/v1/celestia/blob)

<Tip>
  Please note, the node needs some time to sync with other Celestia nodes and download data.
</Tip>

* Examples and descriptions for the API are available in project's readme: [https://github.com/blockscout/blockscout-rs/tree/main/da-indexer#readme](https://github.com/blockscout/blockscout-rs/tree/main/da-indexer#readme)
* More detailed tutorials: [https://docs.celestia.org/](https://docs.celestia.org/)
* Additional info on the integration: [https://www.blog.blockscout.com/celestia-superhighway-supporting-high-data-availability-on-blockscout/](https://www.blog.blockscout.com/celestia-superhighway-supporting-high-data-availability-on-blockscout/)


# Configuration Options
Source: https://docs.blockscout.com/setup/configuration-options

Configuration options and settings for Blockscout deployment.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

Many configurations are handled via [ENV variables](/setup/env-variables). For other options, see the submenu items in this section.


# Admin Panel Usage
Source: https://docs.blockscout.com/setup/configuration-options/admin-panel-usage



<Warning>
  **The Admin Panel is only available to Blockscout Hosted Clients**. It allows admin access to create custom tags, verify contract ownership, review approve, and update tokens, and display additional meta information in the explorer.

  The Admin Panel is activated via the `ADMIN_PANEL_ENABLED` env by the Blockscout team, it will not work for self-hosted versions.
</Warning>

<Info>
  More info coming soon
</Info>


# Automating Restarts
Source: https://docs.blockscout.com/setup/configuration-options/automating-restarts



By default `BlockScout` does not restart if it crashes. To enable automated restarts, set the [environment variable](/setup/env-variables) `HEART_COMMAND` to whatever command you run to start `BlockScout`. Configure the heart beat timeout to change how long it waits before considering the application unresponsive.

At that point, it will kill the current blockscout instance and execute the `HEART_COMMAND`. By default a crash dump is not written unless you set `ERL_CRASH_DUMP_SECONDS` to a positive or negative integer. See the [heart](http://erlang.org/doc/man/heart.html) documentation for more information.


# Charts And Stats
Source: https://docs.blockscout.com/setup/configuration-options/charts-and-stats

New Blockscout stats service

<Frame>
  <img />
</Frame>

## Description

Blockscout provides a way to easily calculate and display chain-relevant charts and statistics. For example, it can calculate and display the number of blocks per day, the average block reward, or the number of active accounts per day.

Statistics are implemented using a separate microservice that is connected to the indexed blockscout database. The source code and full README.md for the service is available here: [https://github.com/blockscout/blockscout-rs/tree/main/stats](https://github.com/blockscout/blockscout-rs/tree/main/stats)

On start, the service performs initial calculations for all charts. After that, each chart updates independently according to its `update_schedule`.

## Cache

<Info>
  It’s better to run the service after blockscout has finished the indexing process. During indexing blockscout database contains partial information about the blockchain, so statistics may be inaccurate.
</Info>

The stats service will try to use cache values for efficient chart recalculation. If you decide to run statistics during indexing, rerun the service with<br />`STATS__FORCE_UPDATE_ON_START=true` env variable once indexing is finished to perform a full update of all charts.

## How to run

Options including docker, docker-compose or building from source. -> [https://github.com/blockscout/blockscout-rs/tree/main/stats#build](https://github.com/blockscout/blockscout-rs/tree/main/stats#build)

## Configs

* Env variables [https://github.com/blockscout/blockscout-rs/tree/main/stats#env](https://github.com/blockscout/blockscout-rs/tree/main/stats#env)
* .env example: [https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-stats.env](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-stats.env)

## Chart Types

Two types of charts are available for the Charts and Stats Section, `Line`charts and `Counter` charts.

### Line Charts

Example line chart where the X axis is date, and the Y axis is some data.

<Frame>
  <img />
</Frame>

### Counter Charts

Single value, typically related to sums.

<Frame>
  <img />
</Frame>

## Chart configuration

Blockscout has a set of predefined charts, which can be enabled or disabled using `charts.toml` file. Default charts config can be found here: [https://github.com/blockscout/blockscout-rs/blob/main/stats/config/charts.toml](https://github.com/blockscout/blockscout-rs/blob/main/stats/config/charts.toml)

This file can be used as a template. Customize by removing unnecessary or unrelated charts from `.toml` file. For example, here is a configuration with only block-related statistics:

```toml theme={null}
[[counters]]
id = "totalBlocks"
title = "Total Blocks"
update_schedule = "0 0 */3 * * * *"

[[counters]]
id = "averageBlockTime"
title = "Average Block Time"
units = "s"
update_schedule = "0 0 15 * * * *"

[[lines.sections]]
id = "blocks"
title = "Blocks"

[[lines.sections.charts]]
id = "newBlocks"
title = "New blocks"
description = "New blocks number"
update_schedule = "0 0 8 * * * *"
drop_last_point = true

[[lines.sections.charts]]
id = "averageBlockSize"
title = "Average block size"
description = "Average size of blocks in bytes"
units = "Bytes"
update_schedule = "0 0 9 * * * *"
drop_last_point = true

[[lines.sections.charts]]
id = "averageBlockRewards"
title = "Average block rewards"
description = "Average amount of distributed reward in tokens per day"
units = "ETH"
update_schedule = "0 0 20 * * * *"
drop_last_point = true
```


# Circle CI Updates
Source: https://docs.blockscout.com/setup/configuration-options/circle-ci-updates



To monitor build status, configure your local [CCMenu](http://ccmenu.org/) with the following url: [`https://circleci.com/gh/poanetwork/blockscout.cc.xml?circle-token=f8823a3d0090407c11f87028c73015a331dbf604`](https://circleci.com/gh/poanetwork/blockscout.cc.xml?circle-token=f8823a3d0090407c11f87028c73015a331dbf604)


# Exchange Rates
Source: https://docs.blockscout.com/setup/configuration-options/exchange-rates



<Info>
  Info on [exchange rate ENVs](/setup/env-variables/backend-env-variables#exchange-rates)
</Info>

<Warning>
  If you are running a split API/Indexer setup: Token and History fetching runs in indexer mode while Coin fetching runs in API mode
</Warning>

Exchange rates can be gathered from a variety of sources and set for coins, tokens and historical rates.

Coin Exchange Rates

Select your preferred service for fetching exchange rates


# Haproxy Settings For Blockscout.Com
Source: https://docs.blockscout.com/setup/configuration-options/haproxy-settings-for-blockscout-com

Blockscout.com uses haproxy for all BlockScout hosted and external instances.

<Tip>
  If you would like to add your instance to Blockscout.com, make the required changes and submit a PR to [https://github.com/blockscout/haproxy-config](https://github.com/blockscout/haproxy-config)
</Tip>

## Instructions

Blockscout uses two-part path names for network urls: the first part (`org`) designates the organization/type of the network, the second part (`netname`) names the network.

**For example:**

* **Eth mainnet:** `https://blockscout.com/eth/mainnet`<br />(`org=eth`, `netname=mainnet`)
* **Ethereum Classic mainnet:**` https://blockscout.com/etc/mainnet`<br />(`org=etc`, `netname=mainnet`)
* **Kovan testnet:** `https://blockscout.com/eth/kovan`<br />(`org=eth`, `netname=kovan`)

### 1. Add a new `org` for your blockscout instance's url

1\) Add a new `acl` under the #**Check for network type** section in the cfg file.

```bash theme={null}
#Check for network type
...
acl is_myorg path_beg -i /myorg
```

2\) Add a corresponding exception `!is_myorg` to the **#default redirect** section

```swift theme={null}
# default redirect
redirect prefix /poa/xdai if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg !is_cookie
```

3\) add `!is_myorg `to **every line **in the** #redirect for networks** section

```swift theme={null}
#redirect for networks
redirect prefix /poa/core if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg is_cookie_core
redirect prefix /poa/sokol if !is_websocket !is_poa !is_etc !is_eth !is_lukso !is_rsk !is_myorg is_cookie_sokol
# do this for every line
...
```

### 2. Add a new acl with your netname

In the **#Check for network name** section add a new `acl` with your `netname` similar to existing ones

```bash theme={null}
#Check for network name
...
acl is_mynet path_beg -i /myorg/mynet
```

### 3) Set the cookie and name of rpc/websockets servers

```csharp theme={null}
#Check for cookies
...
acl is_cookie_mynet hdr_sub(cookie) network=mynet

#Default backends
...
use_backend mynet if is_mynet

#WebSocket backends
...
use_backend mynet_ws if is_cookie_mynet is_websocket
```

### 4. Add new backend sections to the end of the file

Add new `backend_mynet` and `backend_mynet_ws` sections to the end of the file and provide dns names of your BlockScout instances.

**For example:**

```php theme={null}
backend mynet
    #Proxy mode
    mode http

    #Backend queries should not have network prefix, so we delete it
    acl is_mynet path_beg /myorg/mynet
    reqirep ^([^\ ].*)myorg/mynet[/]?(.*) \1\2 if is_mynet

    #Setting headers to mask our query
    http-request set-header X-Forwarded-Host %[req.hdr(Host)]
    http-request set-header X-Client-IP %[src]
    http-request set-header Host my-blockscout-instance.com

    #Specifying cookie to insert
    cookie network insert

    #Server list. Format:
    #server <name> <address>:<port> cookie <network_name> check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none
    server mynet_server my-blockscout-instance.com:443 cookie mynet check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none

backend mynet_ws
    #Check if WebSocket request is correct
    acl hdr_websocket_key      hdr_cnt(Sec-WebSocket-Key)      eq 1
    acl hdr_websocket_version  hdr_cnt(Sec-WebSocket-Version)  eq 1
    http-request deny if ! hdr_websocket_key ! hdr_websocket_version

    #WebSockets should be forwarded, not http proxied
    option forwardfor

    #Setting headers to mask our query
    http-request set-header Host my-blockscout-instance.com
    http-request set-header Origin https://my-blockscout-instance.com

    #Specifying cookie to insert
    cookie network insert

    #Server list. Format:
    #server <name> <address>:<port> cookie <network_name> check inter 60000 fastinter 1000 fall 3 rise 3 check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none maxconn 30000
    server mynet_server my-blockscout-instance.com:443 cookie mynet check inter 60000 fastinter 1000 fall 3 rise 3 ssl verify none maxconn 30000
```

<Warning>
  Change the following parameters to match your specific case
</Warning>

* `backend mynet`:
  * `acl is_...`
  * `reqirep ...`
  * `http-request set-header Host ...`
  * `server mynet_server...` - **don't forget to specify port 443 here**
* `backend mynet_ws`:
  * `http-request set-header Host...`
  * `http-request set-header Origin ...` **don't forget **`https`** here**
  * `server mynet_server...` - **don't forget port 443 here**

<Tip>
  Submit a PR to the configuration repo at [https://github.com/blockscout/haproxy-config](https://github.com/blockscout/haproxy-config)
</Tip>


# Logger Configs
Source: https://docs.blockscout.com/setup/configuration-options/logger-configs

Adjust # of files and max size to impact disc space

Each [umbrella app](/setup/information-and-settings/umbrella-project) (indexer, explorer, block\_scout\_web, ethereum\_json\_rpc) contains a log rotation config in the `prod.exs` file.

<Info>
  *Example:* [*https://github.com/blockscout/blockscout/blob/master/apps/explorer/config/prod.exs#L36-L51*](https://github.com/blockscout/blockscout/blob/master/apps/explorer/config/prod.exs#L36-L51.)
</Info>

```ruby theme={null}
config :logger, :explorer,
  level: :info,
  path: Path.absname("logs/prod/explorer.log"),
  rotate: %{max_bytes: 52_428_800, keep: 19}

config :logger, :reading_token_functions,
  level: :debug,
  path: Path.absname("logs/prod/explorer/tokens/reading_functions.log"),
  metadata_filter: [fetcher: :token_functions],
  rotate: %{max_bytes: 52_428_800, keep: 19}
```

`config :logger` defines several variables including:

* **level**: (`info`, `debug`, `error`) *log level of detail*
* **rotate**: \{max bytes: `52,428,800` *max size in bytes for each file*, keep: `19` *max number of files to store*}

If you are having issues with disc space, change the level, default number of files, and max bytes to consume less space with logs.

Additional log rotation configs for `ecto.log` (DB interactions wrapper) and `error.log` are located in the common config file [https://github.com/blockscout/blockscout/blob/master/config/config.exs#L47-L61](https://github.com/blockscout/blockscout/blob/master/config/config.exs##L47-L61)


# Memory Usage
Source: https://docs.blockscout.com/setup/configuration-options/memory-usage



The work queues for building the index of all blocks, balances (coin and token), and internal transactions can grow quite large. By default, the soft-limit is 1 GiB, which can be changed via the `INDEXER_MEMORY_LIMIT` ENV which is used in runtime config:

[https://github.com/blockscout/blockscout/blob/174bccc7038de5f699109f9ae0c718eefee18142/config/runtime.exs#L15](https://github.com/blockscout/blockscout/blob/174bccc7038de5f699109f9ae0c718eefee18142/config/runtime.exs#L15)

For example, to increase the soft limit to 3GiB:

```
INDEXER_MEMORY_LIMIT=3
```

or (regardless of the case of the letters)

```
INDEXER_MEMORY_LIMIT=3gb
```

or (regardless of the case of the letters)

```
INDEXER_MEMORY_LIMIT=3g
```

This configuration utilizes Bitwise which in our case calculates the result of an [arithmetic left bitshift](/setup/indexing/how-do-i-update-memory-consumption-to-fix-indexer-memory-errors#left-bitshift-conversion-table). The recommended minimum Memory to index Ethereum Mainnet is 30 GiB.

Memory usage is checked once per minute. If the soft-limit is reached, the shrinkable work queues will shed half their load. The shed load will be restored from the database, the same as when a restart of the server occurs, so rebuilding the work queue will be slower, but use less memory.

If all queues are at their minimum size, then no more memory can be reclaimed and an error will be logged.


# My Account Settings
Source: https://docs.blockscout.com/setup/configuration-options/my-account-settings



[My Account](/using-blockscout/my-account) is now available for chains that would like to incorporate personalization into their explorer. You will need to configure several 3rd party accounts to fully interact with the My Account feature. These include:

* [Uberauth](https://hexdocs.pm/ueberauth/readme.html): User authentication & login
* [Sendgrid](https://sendgrid.com/): Watchlist notifications
* [Airtable](https://www.airtable.com/): Public Tag requests via API

Once these are setup, [update your Blockscout instance](/setup/deployment/manual-old-ui) and add the [My Account ENV variables](/setup/env-variables#account-related-env-variables). Below are examples from the [Gnosis Chain instance](https://gnosis.blockscout.com/) with some private info redacted.

```txt theme={null}
ACCOUNT_ENABLED=true
ACCOUNT_AUTH0_DOMAIN=login.blockscout.com
ACCOUNT_AUTH0_CLIENT_ID=...
ACCOUNT_AUTH0_CLIENT_SECRET=...
ACCOUNT_SENDGRID_API_KEY=...
ACCOUNT_SENDGRID_SENDER=noreply@blockscout.com
ACCOUNT_SENDGRID_TEMPLATE=d-...
ACCOUNT_PUBLIC_TAGS_AIRTABLE_URL=https://api.airtable.com/v0/.../Public%20Tags
ACCOUNT_PUBLIC_TAGS_AIRTABLE_API_KEY=key...
ACCOUNT_CLOAK_KEY=...
ACCOUNT_REDIS_URL=redis://redis_db:6379
ACCOUNT_DATABASE_URL=postgresql://user:pass@host:port/db
```

## Airtable Schema

Add `request_type` and `request_id` variables to the airtable when configuring for your My Account settings.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

## List of required variables

The following variables are needed for your airtable.

<Frame>
  <img />
</Frame>


# ReCAPTCHA
Source: https://docs.blockscout.com/setup/configuration-options/recaptcha



<Warning>
  Blockscout currently supports **reCAPTCHA v2 in invisible mode.** Previous frontend versions (**v1.36.x)** support v3, but moving forward we will only support v2.
</Warning>

reCAPTCHA from Google is a free service (with certain [usage limits](https://cloud.google.com/recaptcha/quotas)) designed to protect your site from spam and bots. It can be used in Blockscout to prevent bot activity related to CSV downloads and account validation. reCAPTCHA is turned on by default, but can be disabled by setting `RE_CAPTCHA_DISABLED` to true.

### Obtain your keys

1\) To use reCAPTCHA you will need a SITE KEY and SECRET KEY

1. Go to [https://www.google.com/recaptcha/admin/create](https://www.google.com/recaptcha/admin/create), login to Google with an existing account, and fill in the following info:

   a. **Label**: Private label to identify the instance in your reCAPTCHA admin dashboard.

   b. **reCAPTCHA type**: Select Challenge (v2) and Invisible reCAPTCHA badge

   c. **Domains**: Enter your primary Blockscout domain, all associated subdomains will be covered. You can enter multiple domains, and also localhost for testing if needed.

   d. **Submit**

<Frame>
  <img />
</Frame>

2\) Copy your keys and use them with the following ENV variables to enable reCAPTCHA.

| Backend ENV Variable    | Google reCAPTCHA key |
| ----------------------- | -------------------- |
| `RE_CAPTCHA_SECRET_KEY` | SECRET KEY           |

| Frontend ENV Variable                 | Google reCAPTCHA key |
| ------------------------------------- | -------------------- |
| `NEXT_PUBLIC_RE_CAPTCHA_APP_SITE_KEY` | SITE KEY             |

<Frame>
  <img />
</Frame>

3\) Add the keys to ENV variables to your .env file or at runtime for the backend and frontend containers.

Backend container:

```javascript theme={null}
$ export RE_CAPTCHA_SECRET_KEY=6Le...Qdo
```

Frontend container:

```javascript theme={null}
$ export NEXT_PUBLIC_RE_CAPTCHA_APP_SITE_KEY=6L...IU
```

<Info>
  Once setup, you can view and update your reCAPTCHA settings on the Google admin dashboard at [https://www.google.com/recaptcha/admin](https://www.google.com/recaptcha/admin)
</Info>

### Additional reCAPTCHA ENV info

* Backend reCAPTCHA ENVs are located in the Backend ENVs: Common page in the [CSV exports section](/setup/env-variables/backend-env-variables#csv-export).
* Frontend reCAPTCHA ENVs are located on the Frontend ENVs: Common -> ENVs page in the [External Services section](/setup/env-variables/frontend-common-envs/envs#external-services-configuration).
* Disable reCAPTCHA by setting `RE_CAPTCHA_DISABLED `to true
* Disable checking reCAPTCHA domain names by setting `RE_CAPTCHA_CHECK_HOSTNAME` to false. This will bypass checking the hostname info added during reCAPTCHA setup in Google. \*\*\*\*[More info on domains.](https://developers.google.com/recaptcha/docs/domain_validation)


# Sorting And Pagination
Source: https://docs.blockscout.com/setup/configuration-options/sorting-and-pagination



The sorting module is available for advanced data sorting and pagination. Data can be sorted within a column, via association, or with a dynamic query.

* The feature was introduced here: [https://github.com/blockscout/blockscout/pull/8611](https://github.com/blockscout/blockscout/pull/8611)
* Features are implemented here: [https://github.com/blockscout/blockscout/blob/master/apps/explorer/lib/explorer/sorting\_helper.ex](https://github.com/blockscout/blockscout/blob/master/apps/explorer/lib/explorer/sorting_helper.ex)
* [An Example](/setup/configuration-options/sorting-and-pagination#example) is located at the bottom of this doc.

## **Ordering**

To order any Ecto schema, use the `Explorer.SortingHelper.apply_sorting/3` function. This function requires three arguments:

* The Ecto query to be sorted (`query`)
* User-provided sorting parameters (`sorting`)
* Default sorting parameters (`default_sorting`)

## **Sorting Parameters**

Sorting parameters follow the type `Explorer.SortingHelper.sorting_params/0`, which can be one of the following tuples:

* `{ordering, column}`
* `{ordering, column, binding}`
* `{:dynamic, column, ordering, Ecto.Query.dynamic_expr()}`

**Where:**

* `ordering` can be `:asc`, `:asc_nulls_first`, `:asc_nulls_last`, `:desc`, `:desc_nulls_first`, or `:desc_nulls_last`.
* `column` is an atom representing the column name to sort by.
* `binding` is an atom denoting the association or binding to use for the column.

## Pagination

Pagination is handled by the `Explorer.SortingHelper.page_with_sorting/4` function in conjunction with ordering. It uses the provided `paging_options` along with the sorting parameters to return a paginated query.

We use cursor based pagination because blockchain data may be quite large. After merging default and user provided sorting options we generate a dynamic query with a recursive condition for each column.

Blockscout employs cursor-based pagination for efficient handling of large blockchain datasets. This approach is facilitated by the `Explorer.SortingHelper.page_with_sorting/4` function, which integrates sorting parameters with pagination options.

## **Cursor-Based Pagination**

Cursor-based pagination is particularly suitable for blockchain data due to its potential size and frequent data updates. This method ensures that the same records are not retrieved more than once, even if new data is inserted between requests.

## **Pagination Implementation**

The `page_with_sorting` function accepts the following arguments:

1. The Ecto query object.
2. Paging options that specify the cursor position and the page size.
3. User-provided sorting parameters.
4. Default sorting parameters.

By combining the default and user-provided sorting options, a dynamic query is constructed. This includes 'where' conditions that are applied recursively for each column involved in the sorting. This ensures that the pagination cursor moves accurately through the sorted records.

Using this function, developers can create paginated endpoints that respond quickly and consistently, even with the ever-growing amount of blockchain data.

## Example

```python theme={null}
@default_sorting [
  desc_nulls_last: :circulating_market_cap,
  desc_nulls_last: :fiat_value,
  desc_nulls_last: :holder_count,
  asc: :name,
  asc: :contract_address_hash
]

...

@doc """
Lists the top `t:__MODULE__.t/0`'s'.
"""
@spec list_top(String.t() | nil, [
        Chain.paging_options()
        | {:sorting, SortingHelper.sorting_params()}
        | {:token_type, [String.t()]}
      ]) :: [Token.t()]
def list_top(filter, options \\ []) do
  paging_options = Keyword.get(options, :paging_options, Chain.default_paging_options())
  token_type = Keyword.get(options, :token_type, nil)
  sorting = Keyword.get(options, :sorting, [])

  query = from(t in Token, preload: [:contract_address])

  sorted_paginated_query =
    query
    |> apply_filter(token_type)
    |> SortingHelper.apply_sorting(sorting, @default_sorting)
    |> SortingHelper.page_with_sorting(paging_options, sorting, @default_sorting)

  filtered_query =
    case filter && filter !== "" && Search.prepare_search_term(filter) do
      {:some, filter_term} ->
        sorted_paginated_query
        |> where(fragment("to_tsvector('english', symbol || ' ' || name) @@ to_tsquery(?)", ^filter_term))

      _ ->
        sorted_paginated_query
    end

  filtered_query
  |> Chain.select_repo(options).all()
end
```

User-provided sorting is obtained from the query parameters of a REST API call through the `tokens_sorting/1` function:

```java theme={null}
@spec tokens_sorting(%{required(String.t()) => String.t()}) :: [{:sorting, SortingHelper.sorting_params()}]
def tokens_sorting(%{"sort" => sort_field, "order" => order}) do
  [sorting: do_tokens_sorting(sort_field, order)]
end

def tokens_sorting(_), do: []

defp do_tokens_sorting("fiat_value", "asc"), do: [asc_nulls_first: :fiat_value]
defp do_tokens_sorting("fiat_value", "desc"), do: [desc_nulls_last: :fiat_value]
defp do_tokens_sorting("holder_count", "asc"), do: [asc_nulls_first: :holder_count]
defp do_tokens_sorting("holder_count", "desc"), do: [desc_nulls_last: :holder_count]
defp do_tokens_sorting("circulating_market_cap", "asc"), do: [asc_nulls_first: :circulating_market_cap]
defp do_tokens_sorting("circulating_market_cap", "desc"), do: [desc_nulls_last: :circulating_market_cap]
defp do_tokens_sorting(_, _), do: []
```

This function converts query parameters into sorting parameters understood by the sorting module.


# Tracing
Source: https://docs.blockscout.com/setup/configuration-options/tracing



BlockScout supports tracing via [Spandex](https://github.com/spandex-project/spandex). Each application has its own internally configured tracer.

To enable tracing, visit each application's `config/<env>.ex` and change `disabled?: true` to `disabled?: false`. Do this for each application you'd like included in your trace data.

Currently, only [Datadog](https://www.datadoghq.com/) is supported as a tracing backend, but more will be added soon.

## DataDog

If you would like to use DataDog, after enabling `Spandex`, set `"DATADOG_HOST"` and `"DATADOG_PORT"` environment variables to the host/port that your Datadog agent is running on. For more information on Datadog and the Datadog agent, see the [documentation](https://docs.datadoghq.com/).

## Other

If you want to use a different backend, remove the `SpandexDatadog.ApiServer` `Supervisor.child_spec` from `Explorer.Application` and follow any instructions provided in `Spandex` for setting up that backend.


# Metrics
Source: https://docs.blockscout.com/setup/configuration-options/untitled-2



## Prometheus

BlockScout is setup to export [Prometheus](https://prometheus.io/) metrics at `/metrics`.

1. Install prometheus: `brew install prometheus`
2. Start the web server `iex -S mix phx.server`
3. Start prometheus: `prometheus --config.file=prometheus.yml`

## Grafana

The Grafana dashboard may also be used for metrics display.

1. Install grafana: `brew install grafana`

2. Install Pie Chart panel plugin: `grafana-cli plugins install grafana-piechart-panel`

3. Start grafana: `brew services start grafana`

4. Add Prometheus as a Data Source

   a. `open http://localhost:3000/datasources`

   b. Click "+ Add data source"

   c. Put "Prometheus" for "Name"

   d. Change "Type" to "Prometheus"

   e. Set "URL" to "[http://localhost:9090](http://localhost:9090)"

   f. Set "Scrape Interval" to "10s"

5. Add the dashboards from [https://github.com/deadtrickster/beam-dashboards](https://github.com/deadtrickster/beam-dashboards): For each `*.json` file in the repo.

   a. `open http://localhost:3000/dashboard/import`

   b. Copy the contents of the JSON file in the "Or paste JSON" entry

   c. Click "Load"

6. View the dashboards. (You will need to click-around and use BlockScout for the web-related metrics to show up.)

Examples of dashboards:

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>


# Reown (Previously WalletConnect) Project ID For Contract Read/Write
Source: https://docs.blockscout.com/setup/configuration-options/walletconnect-project-id-for-contract-read-write



<Info>
  The latest versions of Blockscout use Reown (previously WalletConnect) for Read and Write functionality with smart contracts. The frontend variable `NEXT_PUBLIC_WALLET_CONNECT_PROJECT_ID` must be enabled with your project ID for this feature to work.
</Info>

## Setting up a Reown Project ID

1\) Go to [https://cloud.reown.com/sign-in](https://cloud.reown.com/sign-in) and sign in or create an account.

2\) Create a new Project

<Frame>
  <img />
</Frame>

3\) Add your project information (name and project homepage) and click continue.

<Frame>
  <img />
</Frame>

4\) Select **WalletKit** as the SDK.

<Frame>
  <img />
</Frame>

5\) Select **Javascript** as the platform and create your project.

<Frame>
  <img />
</Frame>

6\) Scroll down to see your basic information, including your Project ID. Before using, however, **setup Project Domains**. Please include any urls which host your explorer(s) here.

<Warning>
  This step is important because the Project ID will be exposed in the browser. Setting allowed domains prevents unauthorized usage of your ID.
</Warning>

<Frame>
  <img />
</Frame>

You can also verify your domain domains. This is not required but is recommended for security. Instructions are included in the interface.

<Frame>
  <img />
</Frame>

7\) Copy your project ID and add in the ENV.

<Frame>
  <img />
</Frame>

```javascript theme={null}
$ export NEXT_PUBLIC_WALLET_CONNECT_PROJECT_ID=54b4....8dd05
```

<Tip>
  You Blockscout instance will now support the Reown Project ID for Contract Read and Write functionality. [-> See more front-end ENVs related to Blockchain and contract interaction](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md#blockchain-interaction-writing-to-contract-etc).
</Tip>


# DB Schema
Source: https://docs.blockscout.com/setup/db-schema

Database schema structure and reference for Blockscout.

### Tables

[https://blockscout.github.io/blockscout-db-schema/index.html](https://blockscout.github.io/blockscout-db-schema/index.html)

### Columns

[https://blockscout.github.io/blockscout-db-schema/columns.html](https://blockscout.github.io/blockscout-db-schema/columns.html)

### Constraints

[https://blockscout.github.io/blockscout-db-schema/constraints.html](https://blockscout.github.io/blockscout-db-schema/constraints.html)

### Relationships

[https://blockscout.github.io/blockscout-db-schema/relationships.html](https://blockscout.github.io/blockscout-db-schema/relationships.html)


# Deployment
Source: https://docs.blockscout.com/setup/deployment

Blockscout deployment options

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes**
</Tip>

There are several methods available for deploying Blockscout and associated services (stats, admin etc).

* [Autoscout Deployment](/using-blockscout/autoscout): Use the Blockscout launchpad to deploy an instance in 5 minutes using Blockscout's infrastructure
* [Manual Deployment](/setup/deployment/manual-deployment-guide): Includes instructions for deploying Blockscout with the current frontend and all microservices.
* [Kurtosis Deployment](https://github.com/0xBloctopus/blockscout-package): Plug-and-play explorer bundle by [Bloctopus.io](http://Bloctopus.io) to deploy Blockscout services within any Kurtosis environment, supporting EVM, OP, oe standalone stacks
* [Docker-compose Deployment](/setup/deployment/docker-compose-deployment): Includes current frontend and all microservices
* [Kubernetes Deployment](/setup/deployment/kubernetes-deployment): Includes current frontend and all microservices
* [Manual Deployment](/setup/deployment/manual-old-ui) with backend and **old Blockscout UI (no longer supported)**
* [Frontend migration](/setup/deployment/frontend-migration) (migrating from the previous Blockscout UI to the new UI)
* [Terraform Deployment](/setup/deployment/terraform-deployment) (Polygon Supernets)
* [Ansible Deployment](/setup/deployment/ansible-deployment) (old UI)


# AWS Marketplace (Deprecated)
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace

BlockScout is now available in the Amazon Marketplace.

<Warning>
  AWS Marketplace instance of BlockScout is no longer available. You can follow the [Ansible Deployment instructions](/setup/deployment/ansible-deployment) to setup an instance on AWS.
</Warning>


# AWS EC2 Archive Node Setup With OpenEthereum (Formerly Parity)
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/aws-ec2-archive-node-setup

The following provides an example node setup. Performance related parameters will vary per chain.

<Warning>
  See the [OpenEthereum Documentation](https://openethereum.github.io/wiki/) for complete instructions for any chain setup
</Warning>

<Info>
  Any chain requires an amount of storage capable of storing all archive data. For best performance choose the best available storage device (ie NVMe SSD).
</Info>

1. Setup an EC2 instance and choose the best available storage (ie NVMe SSD).

   [https://aws.amazon.com/ec2/getting-started/](https://aws.amazon.com/ec2/getting-started/)

   * During setup you will [configure Security Groups](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html). For security purposes, you should limit the inbound traffic to RPC and WebSocket interfaces (default ports are `8545` and `8546`). Limit connection to these ports to the BlockScout application server's IP address if setting up BlockScout (find in the details section of your created instance) or to your local network. You can also set limit port connections later through the EC2 -> Security Groups panel.

2. [Connect to your instance using SSH](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AccessingInstancesLinux.html) Specify the private key ( `.pem` ) file, the user name for your AMI, and the public DNS name for your instance. For example, if you used Amazon Linux 2 or the Amazon Linux AMI, the user name is `ec2-user`. If ubuntu, the user name is `ubuntu`. [Find info about your instance](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/connection-prereqs.html#connection-prereqs-get-info-about-instance)

   **Example:**` ssh -i /path/my-key-pair.pem ec2-user@ec2-198-51-100-1.compute-1.amazonaws.com`

3. Install OpenEthereum from [GitHub releases page](https://github.com/openethereum/openethereum/releases) for the corresponding platform

4. Create a config file called node.toml (**see below for config file specs including** [**xDai archive node specs**](/setup/deployment/ansible-deployment/aws-marketplace/aws-ec2-archive-node-setup#xdai-archive-node-configuration)) and edit accordingly `vim node.toml`

5. Connect and Sync an archive node using the config file. `parity --config node.toml`

6. Find your EC2 url to connect with BlockScout: Go to **EC2 Dashboard -> Instances ->** ***corresponding archive node instance*** and record the ip address. When configuring BlockScout you will use this address along with port 8545 to connect via the EthereumJsonRPCHttpURL parameter.

   For example: `192.0.2.1:8545`

**Additional Resources**

* [AWS Marketplace Instructions](/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation)
* [See the xDai Docs for instructions on installing a local instance of xDai using OpenEthereum or Nethermind](https://www.xdaichain.com/for-developers/install-xdai-client).

#### Node.toml file general instructions

Below we provide a general example file as well as the settings we use for our xDai node config. In general:

* Parity should run in "fatdb+archive+traces" mode with `pruning="archive"`, `fatdb="on"`, `tracing="on"`.
* Both RPC and WebSockets interfaces should be opened and allow calls to `"web3","eth","net","parity","pubsub","traces"` APIs.
* A full list of configuration options is available at: [https://wiki.parity.io/Configuring-Parity-Ethereum](https://openethereum.github.io/wiki/Configuring-Parity-Ethereum)

## Configuration file example

The following example file outlines general parameters - Performance-related parameters like `processing_threads`, `server_threads` or `cache_size_db` will vary based on the chain size, available hardware, parity version, general traffic load etc. Often these are adjusted through a trial-and-error process. [See below for xDai Archive Node Specs.](/setup/deployment/ansible-deployment/aws-marketplace/aws-ec2-archive-node-setup#xdai-archive-node-configuration)

### General Specs

```csharp theme={null}
[parity]
chain = "CHAIN NAME or PATH TO SPEC.JSON"

[network]
nat="ext:<PUBLIC IP>"
warp = false

[rpc]
apis = ["web3","eth","net","parity","traces"]
processing_threads = 8
server_threads = 16
interface = "0.0.0.0"
cors=["all"]

[websockets]
port = 8546
interface = "0.0.0.0"
max_connections = 1000
apis = ["web3","eth","net","parity","pubsub","traces"]
origins = ["all"]
hosts = ["all"]

[ui]
disable = true

[snapshots]
disable_periodic = true

[footprint]
tracing = "on"
pruning = "archive"
fat_db = "on"
cache_size_db = 12000
```

### xDai archive node configuration

These are the settings we use to run the xDai archive node.

```csharp theme={null}
[parity]
chain = "xdai"

[network]
nat="ext:<PUBLIC IP>"

[rpc]
apis = ["web3","eth","net", "parity", "traces"]
processing_threads = 50
server_threads = 100
interface = "0.0.0.0"
cors=["all"]

[footprint]
tracing = "on"
pruning = "archive"
fat_db = "on"

[websockets]
max_connections = 1000
interface = "0.0.0.0"
apis = ["web3","eth","net","parity", "pubsub", "traces"]
origins = ["all"]
hosts = ["all"]

[ui]
disable = true

[snapshots]
disable_periodic = true

[mining]
min_gas_price = 1000000000
```

<Tip>
  This instruction was moved from: [https://forum.poa.network/t/example-archive-node-setup-with-parity-on-an-aws-ec2-instance/3077](https://forum.poa.network/t/example-archive-node-setup-with-parity-on-an-aws-ec2-instance/3077)
</Tip>


# Prerequisites & Install Parameters
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation

Prerequisites and installation parameters

## Installation Prerequisites:

#### Required:

1. **Valid email address:** You will receive a temporary password used to access your instance.
2. **Amazon EC2 Public Key (InstanceKey)**. You must create or upload a key pair to your AWS account. [https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html)
3. **ARNCertificate:** You must create or import an ssl certificate to the AWS Certificate Manager service. **This requires a registered domain name** you can access.
   * How to create a certificate: [https://docs.aws.amazon.com/acm/latest/userguide/gs-acm-request-public.html](https://docs.aws.amazon.com/acm/latest/userguide/gs-acm-request-public.html)
   * How to import an existing certificate: [https://docs.aws.amazon.com/acm/latest/userguide/import-certificate.html](https://docs.aws.amazon.com/acm/latest/userguide/import-certificate.html)
4. **Access to a full archive node running a blockchain with an EVM client**. The node will be connected during installation using the EthereumJsonRPC parameters. BlockScout currently supports [Geth](https://ethereum.gitbooks.io/frontier-guide/getting_a_client.html), [Parity](https://wiki.parity.io/Setup), [RSK](https://github.com/rsksmart/rskj/wiki/Install-RskJ-and-join-the-RSK-Wasabi-Mainnet) and [Ganache](https://www.trufflesuite.com/docs/ganache/quickstart).
   * [Example Instructions on creating a local node are available here.](/setup/deployment/ansible-deployment/aws-marketplace/aws-ec2-archive-node-setup)

#### Optional: Route traffic following deployment:

If you leave the `CognitoCallbackDomain` parameter blank during installation and want to use your own domain later, you will need to route traffic to the LoadBalancer and change the Cognito App client settings.

A) Re-route your DNS

* Example instruction to route traffic using Route 53: [https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-to-elb-load-balancer.html](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-to-elb-load-balancer.html)

B) Configure Cognito settings

* Change the callback URL(s) in client settings. [https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-pools-app-settings.html](https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-pools-app-settings.html)

## AWS Installation:

See [Install from AWS Marketplace](/setup/deployment/ansible-deployment/aws-marketplace/install-from-aws-marketplace) for an installation walkthrough.

## Installation Parameters:

Most parameters can be left as default during installation. For a full list of variables see the [ENV variables list](/setup/env-variables).

<Info>
  During configuration, the first item to input is **Stack Name.** This is an identifier that helps you find a particular stack from a list of stacks. It must start with an alphabetic character and can't be longer than 128 characters.
</Info>

The following parameters require a user-input value.

| Parameter               | Value                                                                                                                                                                                                                                                                                                                                                                                                                         |
| ----------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| ARNCertificate          | SSL certificate from point 3 above. More information on certificates is available here: [https://docs.aws.amazon.com/acm/latest/userguide/acm-overview.html](https://docs.aws.amazon.com/acm/latest/userguide/acm-overview.html) Example: `arn:aws:acm:us-east-1:123456789012:certificate/1156aa0c-daa3-4cb1-af6d-6f16202ebf2c`                                                                                               |
| CognitoCallbackDomain   | Add the domain(s) where you will access BlockScout and append "oauth2/idpresponse" to the end. **If you do not have a domain, leave this field blank**. It will be populated with the LoadBalancerDNS created at the end of the process. Example: `https://your.domain/oauth2/idpresponse`                                                                                                                                    |
| CognitoUserEmail        | Enter any valid email. You will receive a temporary password here after deployment. Example: `youremail@email.com`                                                                                                                                                                                                                                                                                                            |
| DBPassword              | Add a secure password here for database access. Must contain only letters and numbers, and be 8 characters or more. **Record this password for later access**.                                                                                                                                                                                                                                                                |
| EthereumJsonRPCHttpURL  | This is the node url used to fetch blocks, transactions, receipts & tokens. See the instructions on setting up a node on AWS for more information. If setup through AWS, you can find the address in EC2 Dashboard -> Instances -> click to corresponding archive node instance. You will retrieve the ip address and add the port number afterwards. The port for Nethermind is 8545. Example: `http://node.ip.address:8545` |
| EthereumJsonRPCTraceURL | Input the same value as above. This is used to fetch internal transactions and block traces. Example: `http://node.ip.address:8545`                                                                                                                                                                                                                                                                                           |
| EthereumJsonRPCWsURL    | The Network RPC endpoint in websocket mode. The default Nethermind port is 8545. Example: `ws://localhost:8545`                                                                                                                                                                                                                                                                                                               |
| GraphiQLTransaction     | Any transaction from the chain can be used. This hash provides a sample query in the GraphIQL Playground and always begins with "0x…" Example: `0x9415741aa80cacb3e2a9f48506010a3f31fddc7e7a00421381b4e4679d5eba20`                                                                                                                                                                                                           |
| IngressIPRangeLB        | IP address range for access to your LoadBalancer instance. Recommend using `0.0.0.0/0` for access from all IPs, or specify your local IP with `your.ip/32`. You can find your ip here: [https://support.google.com/websearch/answer/1696588](https://support.google.com/websearch/answer/1696588)                                                                                                                             |
| InstanceKey             | From step 2 above. The instance key name is located at EC2 Dashboard -> Network & Security -> Key Pairs. It should be available as a dropdown in the template.                                                                                                                                                                                                                                                                |
| SecretKeybase           | Secret key for production assets protection in base64. You can generate this on the command line of your local machine using the following command: "openssl rand -base64 16" Example: `d29vbmcyY2hhaUNvaG5nCg==`                                                                                                                                                                                                             |

<Tip>
  This instruction was moved from [https://forum.poa.network/t/aws-marketplace-installation/3076](https://forum.poa.network/t/aws-marketplace-installation/3076)
</Tip>


# CloudFormation Template
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/cloudformation-template

CloudFormation template and topology for Blockscout AWS deployment.

<Tip>
  The template components and CloudFormation designer view are available in the marketplace listing: [https://aws.amazon.com/marketplace/pp/B07Z78PC2F?qid=1576601748071](https://aws.amazon.com/marketplace/pp/B07Z78PC2F?qid=1576601748071)
</Tip>

<Frame>
  <img />
</Frame>


# Customizing CSS
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/customizing-css

How to customize the Blockscout theme and CSS on AWS Marketplace deployments.

If you would like to customize the theme, follow these steps after a successful deployment:

1. ssh in and stop the BlockScout service:<br />`sudo systemctl stop blockscout.service`
2. Navigate to `blockscout/apps/block_scout_web/assets/css/theme`.
3. Edit `_poa_variables.scss` with appropriate theme colors.
4. Rebuild the static assets: `sudo npm run-script deploy` (from blockscout/apps/block\_scout\_web/assets directory).
5. Restart the BlockScout service:<br />`sudo systemctl start blockscout.service`

The BlockScout application will now be running with the designated theme changes.


# Install From AWS Marketplace
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/install-from-aws-marketplace

AWS Marketplace provides an easy install option for BlockScout

<Info>
  Before you start, make sure you have completed the [prerequisites](/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation).
</Info>

1\) Login to your aws account

2\) Go to [https://aws.amazon.com/marketplace/search/results](https://aws.amazon.com/marketplace/search/results) and search for BlockScout. Click on **BlockScout Blockchain Explorer** to view.

<Frame>
  <img />
</Frame>

3\) From the main BlockScout Page, click the **Continue to** **Subscribe** button (The parameters should be set and do not require any changes)

<Frame>
  <img />
</Frame>

4\) Click **Continue to Configuration**.

<Frame>
  <img />
</Frame>

5\) Select BlockScout BlockChain Explorer as Fulfillment option and Software Version 3 (both should be selected by default) and **Continue to Launch**.

<Frame>
  <img />
</Frame>

6\) Select **Launch CloudFormation** in the Choose Action dropdown, and click **Launch**.

<Frame>
  <img />
</Frame>

7\) Start to configure the stack. Maintain the default selections (Template is ready) and click **Next**.

<Frame>
  <img />
</Frame>

8\) Specify the stack details. Parameters filled in by default can generally be left as-is. For blank items, enter the [chain parameters and environment variables to setup your BlockScout Instance](/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation#installation-parameters).

<Frame>
  <img />
</Frame>

9\) Add any optional items.

* [Resource Tags](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-resource-tags.html?icmpid=docs_cfn_console)
* [Permissions](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-iam-servicerole.html?icmpid=docs_cfn_console)
* [Advanced Stack Options](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-console-add-tags.html?icmpid=docs_cfn_console)

<Frame>
  <img />
</Frame>

10\) Review all the parameters. If everything looks good, acknowledge that CloudFormation might create IAM resources and click **Create stack.**

<Info>
  If any items do not match template specifics, you can fix by clicking previous, changing an item, and returning to the Create stack page.
</Info>

<Frame>
  <img />
</Frame>

11\) Your instance will be located in the CloudFormation section of AWS (search CloudFormation under services to find). You can manage the stack here, including monitoring processes, updating and deleting.

<Frame>
  <img />
</Frame>

12\) When creation is complete, go to the Outputs tab to find the DNS value. Copy and paste into a browser.

<Frame>
  <img />
</Frame>

13\) Enter the username and password from the email you received during setup (email sent to value entered for **CognitoUserEmail** parameter)

<Frame>
  <img />
</Frame>

14\) You will be asked to change your password. Store in a safe place.

<Frame>
  <img />
</Frame>

15\) You should now see your BlockScout instance! Depending on the chain you are running, it may take some time to index the data.

<Frame>
  <img />
</Frame>

For additional configuration options, see:

* [Customizing CSS](/setup/deployment/ansible-deployment/aws-marketplace/customizing-css)
* [Updating BlockScout on AWS](/setup/deployment/ansible-deployment/aws-marketplace/updating-and-redeploying-in-aws)

***

***


# Overview
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/overview

Overview of Blockscout deployment via AWS Marketplace.

<Tip>
  BlockScout on AWS Marketplace is available here: [https://aws.amazon.com/marketplace/pp/B07Z78PC2F?qid=1576601748071](https://aws.amazon.com/marketplace/pp/B07Z78PC2F?qid=1576601748071)
</Tip>

<Frame>
  <img />
</Frame>

## Installation instructions

1. Check that you have the [necessary prerequisites](/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation) (including an [accessible node running a blockchain](/setup/deployment/ansible-deployment/aws-marketplace/aws-ec2-archive-node-setup))
2. Follow the [install instructions](/setup/deployment/ansible-deployment/aws-marketplace/install-from-aws-marketplace)
3. Include [these parameters](/setup/deployment/ansible-deployment/aws-marketplace/aws-marketplace-installation#installation-parameters) during installation
4. Additional options include [updating your instance](/setup/deployment/ansible-deployment/aws-marketplace/updating-and-redeploying-in-aws) or [customizing the theme](/setup/deployment/ansible-deployment/aws-marketplace/customizing-css).

<Warning>
  If you are deploying **without the marketplace**, see the [Ansible Deployment](/setup/deployment/ansible-deployment) section for deployment instructions to the AWS cloud using Terraform.
</Warning>


# Updating & Redeploying In AWS
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-marketplace/updating-and-redeploying-in-aws

How to update or redeploy Blockscout on AWS Marketplace.

To update to the latest version of BlockScout, or redeploy with different chain parameters, you will upload the latest version of BlockScout to your server.

1. Copy the latest version of BlockScout<br />`git clone https://github.com/poanetwork/blockscout`
2. Zip the folder
3. Copy the zip archive to the same root application folder where the current instance resides (this should be standard based on marketplace installation)
4. Access the command line and stop the BlockScout service<br />`sudo systemctl stop blockscout.service`
5. Follow the [manual deployment instructions](/setup/deployment/manual-old-ui) starting with step 2.
6. If required, migrate the previous database following the [AWS RDS migration](https://console.aws.amazon.com/dms/) instructions.


# AWS Permissions & Settings
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-permissions

AWS requirements for deployment

During deployment you will provide credentials to your AWS account. Given the large number of services involved, and the unpredictability of which specific API calls will be needed during provisioning, it is recommended you provide a user account with full access.

You do not need to keep this user around (or enabled) except during the initial provisioning, and for any subsequent runs to update the infrastructure.

You may need to reference these items during deployment:

* [Creating a Secret Key Pair in AWS](/setup/deployment/ansible-deployment/aws-permissions/creating-a-secret-key-pair)
* [Logging in with AWS CLI](/setup/deployment/ansible-deployment/aws-permissions/login-with-aws-cli)
* [Creating an SSL certificate](/setup/deployment/ansible-deployment/aws-permissions/creating-an-aws-certificate-for-ssl)
* [Manually resource cleaning (if deployment fails or you need to remove items)](/setup/deployment/ansible-deployment/aws-permissions/manually-cleaning-terraform-related-instances)

### Resources Created During Deployment

If you do want to restrict the permissions, the following list of resources is created during the deployment process:

* An S3 bucket to keep Terraform state files;
* DynamoDB table to manage Terraform state files leases;
* An SSH keypair (or you can choose to use one which was already created), this is used with any EC2 hosts;
* A VPC containing all of the resources provisioned;
* A public subnet for the app servers, and a private subnet for the database (and Redis for now);
* An internet gateway to provide internet access for the VPC;
* An ALB which exposes the app server HTTPS endpoints to the world;
* A security group to lock down ingress to the app servers to 80/443 + SSH;
* A security group to allow the ALB to talk to the app servers;
* A security group to allow the app servers access to the database;
* An internal DNS zone;
* A DNS record for the database;
* An autoscaling group and launch configuration for each chain;
* A CodeDeploy application and deployment group targeting the corresponding autoscaling groups.

Each configured chain receives its own ASG (autoscaling group) and deployment group. When application updates are pushed to CodeDeploy, all autoscaling groups will deploy the new version using a blue/green strategy. Currently, there is only one EC2 host to run, and the ASG is configured to allow scaling up, but no triggers are set up to actually perform the scaling yet. This is something that may come in the future.

When deployment begins, Ansible creates the S3 bucket and DynamoDB table required for Terraform state management. This ensures that the Terraform state is stored in a centralized location, allowing multiple people to use Terraform on the same infra without interfering with one another. Terraform prevents interference by holding locks (via DynamoDB) against the state data (stored in S3).

<Tip>
  This instruction was moved from [https://forum.poa.network/t/aws-settings-for-blockscout-terraform-deployment/1962](https://forum.poa.network/t/aws-settings-for-blockscout-terraform-deployment/1962)
</Tip>


# Creating A Secret Key Pair
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-permissions/creating-a-secret-key-pair

An access key is needed to utilize the aws cli

1\) Go to MyAccount -> My Security Credentials

<Frame>
  <img />
</Frame>

2\) Expand **Access keys** section and click **Create New Access Key** button

<Frame>
  <img />
</Frame>

3\) Download your key file and store it in a safe place. You will need it to login with the AWS CLI. The file will include:

* AWSAccessKeyID
* AWSSecretKey

<Frame>
  <img />
</Frame>


# Creating An AWS Certificate For SSL
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-permissions/creating-an-aws-certificate-for-ssl

Optional process if you want to use SSL with your BlockScout instance

<Warning>
  If you **do not want to use SSL**, you can disable by adding the `use_ssl = "false"` parameter to the `terraform.tfvars` file.
</Warning>

### To create:

1\) Go to [https://console.aws.amazon.com/acm/](https://console.aws.amazon.com/acm/). Select provision certificates and click on get started:

<Frame>
  <img />
</Frame>

2\) Request a Public Certificate.

<Frame>
  <img />
</Frame>

3\) Add a domain you have access to and click **Next**.

<Info>
  This does not need to be the same domain for deployment - as long as it's a valid ARN on your account it will pass verification.
</Info>

<Frame>
  <img />
</Frame>

4\) Choose your validation method (your preference) and click **Review**.

<Frame>
  <img />
</Frame>

5\) Review your information and click **Confirm and request.**

<Frame>
  <img />
</Frame>

6\) Click **Continue** to begin validation.

<Frame>
  <img />
</Frame>

7\) Confirm the Domain:

* **DNS Validation:** Create a CNAME record in the DNS configuration for each of the domains listed below.
* **Email Validation:** Receive email and follow link

<Frame>
  <img />
</Frame>

8\) Approve the Certificate

<Frame>
  <img />
</Frame>

9\) In the AWS Certificate Manager, click on the domain name to view the certificate details. **Copy and paste your ARN** into the `alb_certificate_arn` field in the `terraform.tfvars` file

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  <img />
</Frame>


# Login With AWS CLI
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-permissions/login-with-aws-cli

How to log in to AWS CLI for Terraform deployment.

use `aws configure` in the cli to connect your account for Terraform deployment. You will be prompted to enter the following. See [Creating a Secret Key Pair](/setup/deployment/ansible-deployment/aws-permissions/creating-a-secret-key-pair) for more information.

* AWS Access Key ID: \<*your\_access\_key\_id*>
* AWS Secret Access Key: \<*your\_secret\_access\_key*>
* Default region name: **us-east-1** Use this, as Terraform has known issues with other regions
* Default output format: json


# Manually Cleaning Terraform Related Instances
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/aws-permissions/manually-cleaning-terraform-related-instances

AWS cleaning resources

<Warning>
  If the deployment process was previously successful, you can run `bin/infra destroy`. Additionally, `bin/infra destroy_setup`will delete the DynamoDB table. [More information on destroying infrastructure is available here](/setup/deployment/ansible-deployment/destroying-provisioned-infrastructure).

  However, in circumstances that rely on insufficient AWS account rights, the deployment process may fail. In this case, `bin/infra destroy_setup` will not work.

  **Additionally, forgetting to clean resources can result in high AWS costs in a short period of time, so it's best to check that all resources have been removed.**
</Warning>

In order to completely manually remove Terraform deployment from AWS you need to clear all related instances of the following services:

* S3
* CodeDeploy
* DynamoDB
* Route 53
* DynamoDB
* VPC
* RDS

### Removing S3 Buckets

1\) In the Find Services box, type in S3 and select **S3, Scalable Storage in the Cloud**.

<Frame>
  <img />
</Frame>

2\) Find related buckets created by Terraform one by one. You can only delete one at a time. They all will be prefixed with `${prefix}` from the Terraform config file. Select a bucket and click **Delete** button. Confirm the deletion. Continue for all related buckets.

<Frame>
  <img />
</Frame>

### Removing CodeDeploy Application

1\) In the Find Services box, type in **CodeDeploy** and select.

<Frame>
  <img />
</Frame>

2\) Select the **Applications** section in the left menu. Click an application in the list (related to Terraform deployment) to select.

<Frame>
  <img />
</Frame>

Click the **Delete Application** button and confirm the deletion.

<Frame>
  <img />
</Frame>

### Remove DynamoDB instance

1\) In the Find Services box, type in **DynamoDB** and select.

<Frame>
  <img />
</Frame>

2\) Remove all related DynamoDBs.

1. Select **Tables** section in the left menu
2. Select related database (typically 1 database per deployment). Select database
3. Click **Delete Table** button.
4. Confirm the deletion.

<Frame>
  <img />
</Frame>

###

1\) In the Find Services box, type in **Route 53** and select.

<Frame>
  <img />
</Frame>

2\) Remove all related Hosted zones.

1. Select hosted zones in left menu.
2. Select related hosted zone.
3. Click **Delete Hosted Zone** button.
4. Confirm the deletion.

<Frame>
  <img />
</Frame>

###

1\) In the Find Services box, type in **VPC** and select.

<Frame>
  <img />
</Frame>

2\) Remove all related subnets. Select **Subnets** section in the left menu, select all related subnets (usually 1 subnet per deployment). Right mouse click or click **Delete subnet** item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

3\) Remove all related route tables. Select **Route tables** section in the left menu, select all related route tables (usually it should be 1 route table for deployment). Right mouse click or click **Delete Route table** item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

4\) Detach all related internet gateways. Select **Internet Gateways** section in the left menu, select all related internet gateways (usually 1 internet gateway per deployment). Right mouse click or click **Detach from VPC** item in **Actions** menu. Confirm the detachment.

<Frame>
  <img />
</Frame>

5\) Remove all related DHCP options sets. Select **DHCP Options Sets** section in the left menu, select all related DHCP options sets (usually 1 DHCP option set per deployment). Right mouse click or click **Delete DHCP options** *set* item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

6\) Remove all related Network ACLs. Select **Network ACLs** section in the left menu, select all related Network ACLs (usually 1 Network ACL per deployment). Right mouse click or click **Delete network ACL** item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

7\) Remove all related Security groups. Select **Security Groups** section in the left menu, select all related Security groups (usually 1 Security group for deployment). Right mouse click or click **Delete security group** item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

8\) Remove all related VPCs. Select **Your VPCs** section in the left menu, select all related VPCs (usually1 VPC for deployment). Right mouse click or click **Delete VPC** item in **Actions** menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

###

1\) In the Find Services box, type in **RDS** and select.

<Frame>
  <img />
</Frame>

2\) Remove all related subnet groups. Select **Subnet groups** section in the left menu, select all related subnet groups (usually 1 subnet group for deployment). Select subnet group and click **Delete** button. Confirm the deletion.

<Frame>
  <img />
</Frame>

3\) Remove all related RDSs. Select **Databases** section in the left menu, select all related databases (usually 1 database for deployment). Select the Database, go to the **Actions** menu, and select **Delete** from the menu. Confirm the deletion.

<Frame>
  <img />
</Frame>

<Tip>
  This instruction was moved from [https://forum.poa.network/t/aws-settings-for-blockscout-terraform-deployment/1962](https://forum.poa.network/t/aws-settings-for-blockscout-terraform-deployment/1962)
</Tip>


# Common Additional Tasks
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/common-additional-tasks

Additional tasks for managing and maintaining Blockscout deployments with Ansible.

## Cleaning Deployment cache

Despite the fact that the Terraform cache is automatically cleared before each deployment, you may also want to manually force the cleaning process. To clear the Terraform cache, Run the `ansible-playbook clean.yml` command.

## Migrating deployer to another machine

You can easily manipulate your deployment from any machine with sufficient prerequisites. If the `upload_debug_info_to_s3` variable is set to true, the deployer will automatically upload your `all.yml` file to the s3 bucket, so you can download it to any other machine. Simply download this file to your `group_vars` folder and your new deployer will pick up the current deployment instead of creating a new one.

## Attaching the existing RDS instance to the current deployment

Rather than create a new database, you may want to add an existing instance to use with the deployment. To do this, configure all proper values at `group_vars/all.yml`, including your DB ID and name, and execute the `ansible-playbook attach_existing_rds.yml` command. This will add the current DB instance into the Terraform-managed resource group. After that run `ansible-playbook deploy_infra.yml` as you normally would.

**Notes**

1. While executing `ansible-playbook attach_existing_rds.yml` the S3 and DynamoDB instances will be automatically created (if `backend` variable is set to `true`) to store Terraform state files.
2. The actual name of your resource must include the prefix you are using with this deployment.<br />Example:<br />Real resource: tf-poa<br />`prefix` variable: tf<br />`chain_db_id` variable: poa
3. Make sure MultiAZ is disabled on your database.
4. Make sure that all the variables at `group_vars/all.yml` are exactly the same as your existing DB.

## Using AWS CodeDeploy to Monitor and manage a BlockScout deployment

BlockScout deployment can be managed through the AWS console. [A brief tutorial is available on our forum](https://forum.poa.network/t/monitor-and-manage-a-blockscout-deployment-using-codedeploy-in-your-aws-console/2499).


# Common Errors And Questions
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/common-errors-and-questions

Common errors and frequently asked questions for Ansible-based deployments.

## S3: 403 error during provisioning

This usually appears if the S3 bucket already exists. Remember, the S3 bucket has a unique global name. Login to your AWS console and create an S3 bucket with the same name you specified in the `bucket` variable to ensure they match.

## Error Applying Plan (diffs didn't match)

If you see something similar to the following:

```swift theme={null}
Error: Error applying plan:

1 error(s) occurred:

* module.stack.aws_autoscaling_group.explorer: aws_autoscaling_group.explorer: diffs didn't match during apply. This is a bug with Terraform and should be reported as a GitHub Issue.

Please include the following information in your report:

    Terraform Version: 0.11.11
    Resource ID: aws_autoscaling_group.explorer
    Mismatch reason: attribute mismatch: availability_zones.1252502072
```

This is due to a bug in Terraform, the fix is to run `ansible-playbook deploy_infra.yml` again, and Terraform will pick up where it left off. This does not always happen, but this is the current workaround if needed.

## Server doesn't start during deployment

Even if the server is configured correctly, sometimes it may not bind the appropriate 4000 port for unknown reasons. If so, simply go to the appropriate nested blockscout folder, kill and rerun the server. For example, you can use the following command: `pkill beam.smp && pkill node && sleep 10 && mix phx.server`.


# Deploying Blockscout
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/deploying-blockscout

Step-by-step guide for deploying Blockscout using Ansible and Terraform.

<Warning>
  Deployment with Terraform 12 is unstable due to these bugs: [#144](https://github.com/poanetwork/blockscout-terraform/issues/144), [#147](https://github.com/poanetwork/blockscout-terraform/issues/147), [#148](https://github.com/poanetwork/blockscout-terraform/issues/148), [#149](https://github.com/poanetwork/blockscout-terraform/issues/149). Please use TF 11.11 - 11.14 and following branch for deployment [https://github.com/poanetwork/blockscout-terraform/tree/before-t12](https://github.com/poanetwork/blockscout-terraform/tree/before-t12)
</Warning>

If you are not using a Mac, skip to step 1 below.

<Warning>
  **Mac Users Only**

  To avoid the following error (which results in a Python crash):

  `TASK [main_software : Fetch environment variables] ************************************ objc[12816]: +[__NSPlaceholderDate initialize] may have been in progress in another thread when fork() was called. objc[12816]: +[__NSPlaceholderDate initialize] may have been in progress in another thread when fork() was called. We cannot safely call it or ignore it in the fork() child process. Crashing instead. Set a breakpoint on objc_initializeAfterForkError to debug.`

  1. Open terminal: `nano .bash_profile`
  2. Add the following line to the end of the file: `export OBJC_DISABLE_INITIALIZE_FORK_SAFETY=YES`
  3. Save, exit, close terminal and re-open the terminal. Check to see that the environment variable is now set: `env`

  (source: [https://stackoverflow.com/questions/50168647/multiprocessing-causes-python-to-crash-and-gives-an-error-may-have-been-in-progr](https://stackoverflow.com/questions/50168647/multiprocessing-causes-python-to-crash-and-gives-an-error-may-have-been-in-progr));
</Warning>

1\) Ensure all [BlockScout prerequisites](/setup/requirements/requirements) are installed with the correct version number

2\) Create the AWS access key and secret access key for user with sufficient permissions;

3\) Create `hosts` file from `hosts.example` (`mv hosts.example hosts`) and adjust to your needs. Each host should represent each BlockScout instance you want to deploy.

<Info>
  Each host name should belong exactly to one group. Also, as per Ansible requirements, hosts and group names should be unique.
</Info>

The simplest `hosts` file with one BlockScout instance will look like:

```csharp theme={null}
[group]
host
```

Where `[group]` is a group name, which will be interpreted as a `prefix` for all created resources and `host` is a name of BlockScout instance.

4\) For each host merge `blockscout.yml.example` and `all.yml.example` config template files in `host_vars` folder into single config file with the same name as in `hosts` file:

```bash theme={null}
cat host_vars/blockscout.yml.example host_vars/all.yml.example > host_vars/host.yml
```

If you have already merged `infrastructure.yml.example` and `all.yml` while deploying the BlockScout infrastructure, you can simply add the `blockscout.yml.example` to the merged file: `cat host_vars/blockscout.yml.example >> host_vars/host.yml`

5\) For each group merge `blockscout.yml.example` and `all.yml.example` config template files in `group_vars` folder into single config file with the same name as group name in `hosts` file:

```bash theme={null}
cat group_vars/blockscout.yml.example group_vars/all.yml.example > group_vars/group.yml
```

If you have already merged `infrastructure.yml.example` and `all.yml` while deploying the BlockScout infrastructure, you can simply add the `blockscout.yml.example` to the merged file: `cat group_vars/blockscout.yml.example >> group_vars/host.yml`

6\) [Adjust the variables](/setup/deployment/ansible-deployment/variables) at `group_vars` and `host_vars`.

<Info>
  You can move variables between host and group vars depending on if variable should be applied to the host or to the entire group.
</Info>

Also, if you need to **distribute variables across all the hosts/groups**, you can add these variables to the `group_vars/all.yml` file.

<Tip>
  More on variable precedence => [Official Ansible Docs](https://docs.ansible.com/ansible/latest/user_guide/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable).
</Tip>

7\) Run `ansible-playbook deploy_software.yml`

8\) When the prompt appears, check that server is running and there is no visual artifacts. The server will be launched at port 4000 at the same machine where you run the Ansible playbooks. If you face any errors you can either fix it or cancel the deployment by pressing **Ctrl+C** and then pressing **A** when additionally prompted.

9\) When the server is ready to be deployed simply press **enter** and deployer will upload Blockscout to the appropriate S3.

10\) Two other prompts will appear to ensure your will on updating the Parameter Store variables and deploying the BlockScout through the CodeDeploy. Both **yes** and **true** will be interpreted as the confirmation.

11\) (optional) If the deployment fails, you can use the following tags to repeat the particular steps of the deployment:

* build
* update\_vars
* deploy

12\) Monitor and manage your deployment at [CodeDeploy](https://console.aws.amazon.com/codesuite/codedeploy/applications) service page at AWS Console.


# Deploying The Blockscout Infrastructure
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/deploying-the-blockscout-infrastructure

Guide to deploying the infrastructure required for Blockscout using Ansible and Terraform.

<Warning>
  Deployment with Terraform 12 is unstable due to these bugs: [#144](https://github.com/poanetwork/blockscout-terraform/issues/144), [#147](https://github.com/poanetwork/blockscout-terraform/issues/147), [#148](https://github.com/poanetwork/blockscout-terraform/issues/148), [#149](https://github.com/poanetwork/blockscout-terraform/issues/149). Please use TF 11.11 - 11.14 and following branch for deployment [https://github.com/poanetwork/blockscout-terraform/tree/before-t12](https://github.com/poanetwork/blockscout-terraform/tree/before-t12)
</Warning>

<Tip>
  Go to [Deploying BlockScout](/setup/deployment/ansible-deployment/deploying-blockscout) if you already have an infrastructure and simply want to install or update your BlockScout instance.
</Tip>

1\) Check that all [infrastructure prerequisites](/setup/deployment/ansible-deployment/prerequisites) are installed with the correct version number.

2\) Create the AWS access key and secret access key for user with sufficient permissions;

3\) Create `hosts` file from `hosts.example` (`mv hosts.example hosts`) and adjust to your needs. Each host should represent each BlockScout instance you want to deploy.

<Info>
  Each host name should belong exactly to one group. Also, per Ansible requirements, hosts and groups names should be unique.
</Info>

The simplest `hosts` file with one BlockScout instance will look like:

```csharp theme={null}
[group]
host
```

Where `[group]` is a group name, which will be interpreted as a `prefix` for all created resources and `host` is a name of BlockScout instance.

4\) For each host merge `infrastructure.yml.example` and `all.yml.example` config template files in `host_vars` folder into single config file with the same name as in `hosts` file:

```bash theme={null}
cat host_vars/infrastructure.yml.example host_vars/all.yml.example > host_vars/host.yml
```

5\) For each group merge `infrastructure.yml.example` and `all.yml.example` config template files in `group_vars` folder into single config file with the same name as group name in `hosts` file:

```bash theme={null}
cat group_vars/infrastructure.yml.example group_vars/all.yml.example > group_vars/group.yml
```

6\) [Adjust the variables](/setup/deployment/ansible-deployment/variables) at `group_vars` and `host_vars`.

<Info>
  You can move variables between host and group vars depending on if variable should be applied to the host or to the entire group.
</Info>

Also, if you need to **distribute variables across all the hosts/groups**, you can add these variables to the `group_vars/all.yml` file.

<Tip>
  More on variable precedence => [Official Ansible Docs](https://docs.ansible.com/ansible/latest/user_guide/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable).
</Tip>

7\) Run `ansible-playbook deploy_infra.yml`

* During the deployment the "diffs didn't match" error may occur, it will be ignored automatically. If Ansible play recap shows 0 failed plays, then the deployment was successful despite the error.

* Optionally, you may want to check the variables that were uploaded to the [Parameter Store](https://console.aws.amazon.com/systems-manager/parameters) at AWS Console.


# Destroying Provisioned Infrastructure
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/destroying-provisioned-infrastructure

Instructions for destroying provisioned infrastructure with Ansible and Terraform.

<Warning>
  Deployment with Terraform 12 is unstable due to these bugs: [#144](https://github.com/poanetwork/blockscout-terraform/issues/144), [#147](https://github.com/poanetwork/blockscout-terraform/issues/147), [#148](https://github.com/poanetwork/blockscout-terraform/issues/148), [#149](https://github.com/poanetwork/blockscout-terraform/issues/149). Please use TF 11.11 - 11.14 and following branch for deployment [https://github.com/poanetwork/blockscout-terraform/tree/before-t12](https://github.com/poanetwork/blockscout-terraform/tree/before-t12)
</Warning>

First, remove autoscaling groups (ASG) deployed via CodeDeploy manually since Terraform doesn't track them and will miss them during the automatic destroy process. Once ASG is deleted you can use the `ansible-playbook destroy.yml` playbook to remove the rest of the generated infrastructure.

Make sure to check the playbook output since in some cases it may not delete everything. Check the error description for details.

<Warning>
  While Terraform is stateful, Ansible is stateless, so if you modify `bucket` or `dynamodb_table` variables and run `destroy.yml` or `deploy_infra.yml` playbooks, it will not alter the current S3/Dynamo resources names, but create new resources. Moreover, altering the `bucket` variable will make Terraform forget about existing infrastructure and, as a consequence, redeploy it. If it is absolutely necessary for you to alter the S3 or DynamoDB names, perform this operation manually and then change the appropriate variable accordingly.
</Warning>

<Info>
  Changing the `backend` variable will force Terraform to forget about created infrastructure, since it will start searching the current state files locally instead of remotely.
</Info>


# Overview
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/overview

Overview of Ansible playbooks and infrastructure for Blockscout deployment.

## Playbook Overview

<Info>
  The playbook infrastructure currently only supports [AWS](/setup/deployment/ansible-deployment#using-aws-codedeploy-to-monitor-and-manage-a-blockscout-deployment) as a cloud provider. If using another provider, please see [manual deployment](/setup/deployment/manual-old-ui).
</Info>

We use [Ansible](https://docs.ansible.com/ansible/latest/index.html) & [Terraform](https://www.terraform.io/intro/getting-started/install.html) to build the correct infrastructure to run BlockScout. The playbook repository is located at [https://github.com/poanetwork/blockscout-terraform](https://github.com/poanetwork/blockscout-terraform).

In the root folder you will find Ansible Playbooks to create all necessary infrastructure to deploy BlockScout. The `lambda` folder also contains a set of scripts that may be useful in your BlockScout infrastructure.

1. [Deploying the Infrastructure](/setup/deployment/ansible-deployment/deploying-the-blockscout-infrastructure). This section describes all the steps to deploy the virtual hardware that is required for production instance of BlockScout. Skip this section if you do have an infrastructure and simply want to install or update your BlockScout.
2. [Deploying BlockScout](/setup/deployment/ansible-deployment/deploying-blockscout). Follow this section to install or update your BlockScout instance.
3. [Destroying Provisioned Infrastructure](/setup/deployment/ansible-deployment/destroying-provisioned-infrastructure). Refer to this section if you want to destroy your BlockScout installation.


# Prerequisites
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/prerequisites

Prerequisites and dependencies for Ansible-based Blockscout deployment.

Playbooks rely on Terraform, the stateful infrastructure-as-a-code software tool. It allows you to modify and recreate single and multiple resources depending on your needs.

This version of playbooks supports the multi-hosts deployment, which means that test BlockScout instances can be built on remote machines. In that case, you will need to have the Ansible, installed on jumpbox (controller) and all the prerequisites described below, installed on runners.

### Infrastructure Prerequisites

|                                          |                                                                                          |
| ---------------------------------------- | ---------------------------------------------------------------------------------------- |
| Dependency name                          | Installation method                                                                      |
| Terraform >=0.11.11 \<= 0.11.14          | [Installation guide](https://learn.hashicorp.com/terraform/getting-started/install.html) |
| Python 3                                 | `apt install python3.7`                                                                  |
| Python3-pip                              | `apt install python3-pip`                                                                |
| Ansible >=2.8.x                          | `pip3 install ansible`                                                                   |
| boto & boto3 & botocore python 3 modules | `pip3 install boto boto3 botocore`                                                       |

### BlockScout Prerequisites

|                                        |                                                                                          |
| -------------------------------------- | ---------------------------------------------------------------------------------------- |
| Dependency name                        | Installation method                                                                      |
| Terraform >=0.11 \<= 0.11.14           | [Installation guide](https://learn.hashicorp.com/terraform/getting-started/install.html) |
| Python 3                               | `apt install python3.7`                                                                  |
| Python3-pip                            | `apt install python3-pip`                                                                |
| Ansible >=2.8.x                        | `pip3 install ansible`                                                                   |
| boto & boto3 & botocore python modules | `pip3 install boto boto3 botocore`                                                       |
| AWS CLI                                | `pip3 install awscli`                                                                    |
| All BlockScout prerequisites           | [See BlockScout Requirements](/setup/requirements/requirements)                          |


# Variables
Source: https://docs.blockscout.com/setup/deployment/ansible-deployment/variables

ENV variables must be configured per chain

## Configuration

There are three groups of variables required to build BlockScout. The first is required to create infrastructure, the second to build BlockScout instances and the third is required both for infra and BS itself.

For your convenience we have divided variable templates into three files accordingly - `infrastructure.yml.example`, `blockscout.yml.example` and `all.yml.example` . Also we have divided those files to place them in the `group_vars` and in `host_vars` folders, so you will not have to repeat some of the variables for each host/group.

To deploy BlockScout, you will setup the following set of files for each instance:

```python theme={null}
/
| - group_vars
|   | - group.yml (combination of [blockscout+infrastructure+all].yml.example)
|   | - all.yml (optional, one for all instances)
| - host_vars
|   | - host.yml (combination of [blockscout+infrastructure+all].yml.example)
| - hosts (one for all instances)
```

The subsections below describe the variables you may want to adjust.

* [Infrastructure Variables](/setup/deployment/ansible-deployment/variables#infrastructure-variables)
* [BlockScout Variables](/setup/deployment/ansible-deployment/variables#blockscout-detail-variables)
* [Common (All) Variables](/setup/deployment/ansible-deployment/variables#common-variables)

## Infrastructure Variables

* `terraform_location` is an address of the Terraform binary on the builder;
* `dynamodb_table` represents the name of table that will be used for Terraform state lock management;
* If `ec2_ssh_key_content` variable is not empty, Terraform will try to create EC2 SSH key with the `ec2_ssh_key_name` name. Otherwise, the existing key with `ec2_ssh_key_name` name will be used;
* `instance_type` defines a size of the Blockscout instance that will be launched during the deployment process;
* `vpc_cidr`, `public_subnet_cidr`, `db_subnet_cidr` represents the network configuration for the deployment. Usually you want to leave it as is. However, if you want to modify it, please, expect that `db_subnet_cidr` represents not a single network, but a group of networks started with defined CIDR block increased by 8 bits.

<Info>
  Example: Number of networks: 2 `db_subnet_cidr`: "10.0.1.0/16" Real networks: 10.0.1.0/24 and 10.0.2.0/24
</Info>

* An internal DNS zone with`dns_zone_name` name will be created to take care of BlockScout internal communications;
* The `root_block_size` is the amount of storage on your EC2 instance. This value can be adjusted by how frequently logs are rotated. Logs are located in `/opt/app/logs` of your EC2 instance;
* Each of the `db_*` variables configures the database for each chain. Each chain will have the separate RDS instance;
* `instance_type` represent the size of the EC2 instance to be deployed in production;
* `use_placement_group` determines whether or not to launch BlockScout in a placement group.

## BlockScout Variables

* `blockscout_repo` - a direct link to the BlockScout repo;
* `branch` - maps branch at `blockscout_repo` to each chain;
* Specify the `merge_commit` variable if you want to merge any of the specified `chains` with the commit in the other branch. Usually used to update production branches with the releases from master branch;
* `skip_fetch` - if this variable is set to `true` , BlockScout repo will not be cloned and the process will start from building the dependencies. Use this variable to prevent playbooks from overriding manual changes in cloned repo;
* `ps_*` variables represents a connection details to the test Postgres database. This **is not installed automatically**, so make sure `ps_*` credentials are valid before starting the deployment;

## Common (All) Variables

* `ansible_host` - is an address where BlockScout will be built. If this variable is set to localhost, also set `ansible_connection` to `local` for better performance.
* `chain` variable set the name of the network (Kovan, Core, xDAI, etc.). Will be used as part of the infrastructure resource names.
* `env_vars` represents the set of environment variables used by BlockScout. [They are available here.](/setup/env-variables)
  * One can define `BUILD_*` set of the variables, where asterisk stands for any environment variables. All variables defined with `BUILD_*` will override default variables while building the dev server.
* `aws_access_key` and `aws_secret_key` is a credentials pair that provides access to AWS for the deployer; You can use the `aws_profile` instead. In that case, AWS CLI profile will be used. Also, if none of the access key and profile provided, the `default` AWS profile will be used. The `aws_region` should be left at `us-east-1` as some of the other regions fail for different reasons;
* `backend` variable defines whether deployer should keep state files remote or locally. Set `backend` variable to `true` if you want to save state file to the remote S3 bucket;
* `upload_config_to_s3` - set to `true` if you want to upload config `all.yml` file to the S3 bucket automatically after the deployment. Will not work if `backend` is set to false;
* `upload_debug_info_to_s3` - set to `true` if you want to upload full log output to the S3 bucket automatically after the deployment. Will not work if `backend` is set to false.

<Warning>
  Locally logs are stored at `log.txt` which is not cleaned automatically. Do not forget to clean manually or use the `clean.yml` playbook
</Warning>

* `bucket` represents a globally unique name of the bucket where your configs and state will be stored. It will be created automatically during the deployment;

<Warning>
  a chain name SHOULD NOT be more than 5 characters. Otherwise, it will throw an error because the aws load balancer name should not be greater than 32 characters.
</Warning>


# Cosmos Based Chains
Source: https://docs.blockscout.com/setup/deployment/cosmos-based-chains

Using Blockscout as an explorer for Cosmos-based chains with SHUTTLE proxy.

With the [SHUTTLE proxy server developed by Fair Math](https://github.com/fairmath/shuttle/), Blockscout can be used as an out-of-the-box explorer for Cosmos-based chains. [Visit the open-source Fair Math repo for instructions on running SHUTTLE](https://github.com/fairmath/shuttle/).

SHUTTLE works as a proxy on websocket connection and HTTP requests. Incoming JSON RPC requests are translated to corresponding Cosmos HTTP requests and as a result transmitted in the Ethereum format.

<Info>
  The project is currently under development with new features and methods in progress. Community involvement is also encouraged to help build out full compatibility.
</Info>

The following methods are currently supported, meaning core processes like indexing blocks, transactions, internal transactions, and coin balances are functional.

```
eth_blockNumber
eth_getBalance
eth_getBlockByHash
eth_getBlockByNumber
eth_getTransactionByHash
eth_getTransactionByBlockHashAndIndex
eth_getTransactionByBlockNumberAndIndex
eth_getTransactionReceipt
```

These methods are not yet implemented:

```
eth_call
eth_getCode
eth_getUncleByBlockHashAndIndex
eth_getLogs
```

As a result, the following functionality is limited:

* The explorer doesn't detect smart contracts, meaning all addresses are displayed as EoAs. Smart contract verification and interaction doesn't yet work and tokens and their balances are not detected.

* Transaction revert reasons, token metadata, and NFT instance metadata are not yet available.


# Docker Compose Deployment
Source: https://docs.blockscout.com/setup/deployment/docker-compose-deployment

For local builds

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [Get Started Now](/using-blockscout/autoscout) and have **your explorer up-and-running in minutes.**
</Tip>

<Info>
  Please see [https://github.com/blockscout/blockscout/tree/master/docker-compose](https://github.com/blockscout/blockscout/tree/master/docker-compose) for all required information.
</Info>

### Prerequisites

* Docker v20.10+
* Docker-compose 2.x.x+
* Running Ethereum JSON RPC client

### Building Docker containers from source

```bash theme={null}
cd ./docker-compose
docker compose up --build
```

<Warning>
  **Note**: if you don't need to make backend customizations, you can run `docker compose up` in order to launch from pre-build backend Docker image. This will be much faster.
</Warning>

This command uses `docker-compose.yml` by-default, which builds the backend of the explorer into the Docker image and runs 9 Docker containers:

* Postgres 17.x database, which will be available at port 7432 on the host machine.
* Redis database of the latest version.
* Blockscout backend with api at /api path.
* Nginx proxy to bind backend, frontend and microservices.
* Blockscout explorer at [http://localhost](http://localhost).

and 4 containers for microservices (written in Rust):

* [Stats](https://github.com/blockscout/blockscout-rs/tree/main/stats) service with a separate Postgres 14 DB.
* [Sol2UML visualizer](https://github.com/blockscout/blockscout-rs/tree/main/visualizer) service.
* [Sig-provider](https://github.com/blockscout/blockscout-rs/tree/main/sig-provider) service.

<Warning>
  **Note for Linux users**: Linux users who run Blockscout in docker **with a local node** need to run the node on [http://0.0.0.0/](http://0.0.0.0/) rather than [http://127.0.0.1/](http://127.0.0.1/)
</Warning>

### Configs for different Ethereum clients

The repo contains built-in configs for different JSON RPC clients without the need to build the image.

|                                  |                                                     |
| -------------------------------- | --------------------------------------------------- |
| **JSON RPC Client**              | **Docker compose launch command**                   |
| Erigon                           | `docker compose -f erigon.yml up -d`                |
| Geth (suitable for Reth as well) | `docker compose -f geth.yml up -d`                  |
| Geth Clique                      | `docker compose -f geth-clique-consensus.yml up -d` |
| Nethermind, OpenEthereum         | `docker compose -f nethermind up -d`                |
| Anvil                            | `docker compose -f anvil.yml up -d`                 |
| HardHat network                  | `docker compose -f hardhat-network.yml up -d`       |

* Run only the explorer without DB: `docker compose -f external-db.yml up -d`. In this case, no db container is created. And it assumes that the DB credentials are provided through `DATABASE_URL` environment variable on the backend container.
* Running explorer with external backend: `docker compose -f external-backend.yml up -d`
* Running explorer with external frontend: `docker compose -f external-frontend.yml up -d`
* Running all microservices: `docker compose -f microservices.yml up -d`

All of the configs assume the Ethereum JSON RPC is running at [http://localhost:8545](http://localhost:8545).

In order to stop launched containers, run `docker compose -d -f config_file.yml down`, replacing `config_file.yml` with the file name of the config which was previously launched.

You can adjust BlockScout environment variables:

* for backend in `./envs/common-blockscout.env`
* for frontend in `./envs/common-frontend.env`
* for stats service in `./envs/common-stats.env`
* for visualizer in `./envs/common-visualizer.env`

Descriptions of the ENVs are available

* for [backend](/setup/env-variables/backend-env-variables)
* for [frontend](/setup/env-variables/frontend-common-envs)

### Running via Makefile

Prerequisites are the same, as for docker-compose setup.

Start all containers:

```bash theme={null}
cd ./docker
make start
```

Stop all containers:

```bash theme={null}
cd ./docker
make stop
```

<Warning>
  **Note**: Makefile uses the same .env files since it is running docker-compose services inside.
</Warning>


# Frontend Migration
Source: https://docs.blockscout.com/setup/deployment/frontend-migration

Options and instructions for migrating to the new Blockscout frontend.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

The new frontend includes generalized support for L2s including views for attributes such as Index, L1 Timestamp, Size, L1 tx hash, L1 block number, and Batch root, new UI features and enhancements like the DApp marketplace and advanced statistics, and a new micro services infrastructure.

There are several options when deploying the new frontend and migrating your instance. You can either deploy in an all-in-one container, or deploy the frontend separately and connect it to the backend for more flexibility. If you have a custom backend (have made significant changes to the indexer etc) please use option 3.

<Tip>
  If you need help or would like Blockscout to assist with migration or hosting please [reach out in our Discord](https://discord.com/invite/blockscout).
</Tip>

1. [**All-in-one**](/setup/deployment/frontend-migration/all-in-one-container): This is an easier deployment process but less flexible. It will deploy everything within a single docker container. **DO NOT use if you plan to host your frontend separately or want to make significant changes to the frontend.**
2. [**Separate frontend**](/setup/deployment/frontend-migration/separate-frontend): Deploy the frontend first, then connect it to the backend. This lets you make more front-end customizations, and gives you access to all images etc. **Use this method to run a separate frontend instance.**
3. [**Customized backend**](/setup/deployment/frontend-migration/customized-backend): If you've customized the indexer and don't want to override it, keep your previous backend customizations and only deploy the frontend container.


# All In One Container
Source: https://docs.blockscout.com/setup/deployment/frontend-migration/all-in-one-container

Migrate to the new frontend using Docker

<Info>
  You will use the [`docker-compose.yml`](https://github.com/blockscout/blockscout/blob/master/docker-compose/docker-compose.yml) file.
</Info>

## Prerequisites

* Docker v20.10+
* Docker-compose 2.x.x+
* Running Ethereum JSON RPC client

Please see [https://github.com/blockscout/blockscout/tree/master/docker-compose](https://github.com/blockscout/blockscout/tree/master/docker-compose) for additional information

## Migration

### 1) Pull changes from the master branch

We assume Blockscout is already deployed in your environment.

```bash theme={null}
git pull origin master
```

### 2) Navigate to the docker compose folder

```bash theme={null}
cd docker-compose
```

### 3) Adjust backend envs for your instance

Replace the example environment variables in the `environment:` list of the `docker-compose.yml` file.

```bash theme={null}
cat docker-compose.yml
```

By default, standard test setup ENV variables (anvil) are set in the `environment:` list. Replace these with env vars from your existing backend. The only one you **NEED to keep** is `API_V2_ENABLED='true'` . Any values added here will override existing variables when starting the docker container.

```bash theme={null}
environment:
        ETHEREUM_JSONRPC_VARIANT: 'anvil'
        ETHEREUM_JSONRPC_HTTP_URL: http://host.docker.internal:8545/
        ETHEREUM_JSONRPC_WS_URL: ws://host.docker.internal:8545/
        INDEXER_DISABLE_INTERNAL_TRANSACTIONS_FETCHER: 'true'
        INDEXER_DISABLE_PENDING_TRANSACTIONS_FETCHER: 'true'
        DATABASE_URL: postgresql://postgres:@host.docker.internal:7432/blockscout?ssl=false
        ECTO_USE_SSL: 'false'
        SECRET_KEY_BASE: '56NtB48ear7+wMSf0IQuWDAAazhpb31qyc7GiyspBP2vh7t5zlCsF5QDv76chXeN'
        CHAIN_ID: '1337'
        API_V2_ENABLED: 'true'
        MIX_ENV: 'prod'
```

### 4) Run docker compose

Run all containers (up) and run processes in the background (-d).

```bash theme={null}
docker-compose up -d
```

Check progress and view containers:

```bash theme={null}
Docker ps
```

### 5) Check the proxy configuration

```bash theme={null}
cd proxy
Cat default.conf.template
```

Unless you overrode the default configs, you will see the default port for the backend is 4000, and 3000 for the frontend. However, these are not exposed because they are running within the container. **This means localhost:3000 will not work.**

Since the proxy is in place (listen 80) the whole application should default to port 80 (which is just localhost). So your instance with the new frontend should now be served on localhost. [More details about the recommended proxy setup](/setup/deployment/frontend-migration/proxy-setup).

<Info>
  It may take several minutes for the frontend to propagate during this process.
</Info>

### 6) Adjust frontend ENVs if needed

There are several required ENVs for the frontend. If required variables are missing or invalid the frontend will show in error message and will not run the app.

* The common list of [frontend ENVs and descriptions](/setup/env-variables/frontend-common-envs).
* A detailed list with all available ENVs is in the [frontend repo folder.](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md)

To adjust, stop the frontend container, update the env file (or pass variables directly), and restart the container.

### 7) Check Microservice ENVs

Typically the default values will provide what you need for the [`common-visualizer.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-visualizer.env), [`common-stats.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-stats.env), and [`common-smart-contract-verifier.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-smart-contract-verifier.env) files.

Note that in the `smart-contract-verifier.envs` the `SMART_CONTRACT_VERIFIER__SOLIDITY__FETCHER__LIST__LIST_URL` variable is different depending on your OS. The default is Linux, if you are running macOS or Windows be sure to comment out the appropriate variables.


# Customized Backend
Source: https://docs.blockscout.com/setup/deployment/frontend-migration/customized-backend



<Info>
  You will use the [`external-backend.yml`](https://github.com/blockscout/blockscout/blob/master/docker-compose/external-backend.yml)file.
</Info>

## Prerequisites

* Docker v20.10+
* Docker-compose 2.x.x+
* Running Ethereum JSON RPC client

Please see [https://github.com/blockscout/blockscout/tree/master/docker-compose](https://github.com/blockscout/blockscout/tree/master/docker-compose) for additional information

### 1) Pull changes from the Blockscout master branch

We assume Blockscout is already deployed in your environment.

```sh theme={null}
git pull origin master
```

### 2) Navigate to the docker compose folder

```bash theme={null}
cd docker-compose
```

### 3) Run docker compose with BACK\_PROXY\_PASS variable.

You will pass in the backend proxy url when running docker compose. The standard configuration for the backend is `http//host.docker.internal:4000` but if you've made any changes pass in your url.

Run all containers (up) and run processes in the background (-d).

```javascript theme={null}
BACK_PROXY_PASS=http//host.docker.internal:4000 docker compose -f external-backend.yml up -d
```

View progress and check containers

```powershell theme={null}
Docker ps
```

### 4) Check the proxy configuration

```sh theme={null}
cd proxy
Cat default.conf.template
```

Unless you overrode the default configs (or did not provide the `FRONT_PROXY_PASS` variable) , you will see the default port for the backend is `4000`, and `3000` for the frontend.

However, with the proxy setup the whole application will default to port `80` (which is just localhost). Your frontend instance should now be served on localhost. [More details about the recommended proxy setup](/setup/deployment/frontend-migration/proxy-setup).

<Info>
  It may take several minutes for the frontend to propagate during this process.
</Info>

### 5) Adjust frontend ENVs if needed

There are several required ENVs for the frontend. If required variables are missing or invalid the frontend will show in error message and will not run the app.

* The common list of [frontend ENVs and descriptions](/setup/env-variables/frontend-common-envs).
* A detailed list with all available ENVs is in the [frontend repo folder.](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md)

To adjust, stop the frontend container, update the env file (or pass variables directly), and restart the container.

### 6) Check Microservice ENVs

Typically the default values will provide what you need for the [`common-visualizer.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-visualizer.env), [`common-stats.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-stats.env), and [`common-smart-contract-verifier.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-smart-contract-verifier.env) files.

Note that in the `smart-contract-verifier.envs` the `SMART_CONTRACT_VERIFIER__SOLIDITY__FETCHER__LIST__LIST_URL` variable is different depending on your OS. The default is Linux, if you are running macOS or Windows be sure to comment out the appropriate variables.


# FAQs
Source: https://docs.blockscout.com/setup/deployment/frontend-migration/faqs



<Warning>
  🚧 Under Construction
</Warning>

If you have an issue that isn't addressed, please [contact us in Discord](https://discord.gg/blockscout) for troubleshooting.

<AccordionGroup>
  <Accordion title="Are there any additional tutorials for Blockscout deployment?">
    We are currently working on more tutorials from the team. There are some user and community generated videos available here: [https://drive.google.com/drive/folders/1dH-ZxV1ShQ-cb7gObTXs3MtwSqVNJOqW](<https://drive.google.com/drive/folders/1dH-ZxV1ShQ-cb7gObTXs3MtwSqVNJOqW >)
  </Accordion>

  <Accordion title="Where are the environmental variable (ENV) settings located?">
    * Frontend envs: [https://github.com/blockscout/frontend/blob/main/docs/ENVS.md](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md)
    * Backend envs: [https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-blockscout.env](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-blockscout.env)
  </Accordion>

  <Accordion title="How do I connect the frontend to the backend?">
    This is done through the [proxy setup](/setup/deployment/frontend-migration/proxy-setup). Ensure you've added the `API_V2_ENABLED='true'` in your blockscout instance.
  </Accordion>

  <Accordion title="Do the frontend and backend need to be under the same domain?">
    Yes. Be sure to proxy all /api, /socket requests to the backend application and all other requests to the frontend. More info on the [proxy setup](/setup/deployment/frontend-migration/proxy-setup) page.
  </Accordion>

  <Accordion title="What are the variable settings for a Polygon Edge client?">
    Be sure to set the following envs when setting up a Polygon Edge instance:

    * `ETHEREUM_JSONRPC_VARIANT=geth`
    * `INDEXER_INTERNAL_TRANSACTIONS_TRACER_TYPE=polygon_edge`
  </Accordion>

  <Accordion title="Blockscout API/indexer is using 100% CPU, what should I do?">
    You should allocate more computing resources/cores to the instance.
  </Accordion>

  <Accordion title="What should I set the proxy\_pass variable to?">
    Typically you should set to [http://youripaddress:your\_port\_number](http://youripaddress:8153/;). Blockscout may not work if you set to [http://0.0.0.0:](http://0.0.0.0:8153/;)your\_port\_number
  </Accordion>
</AccordionGroup>


# Proxy Setup
Source: https://docs.blockscout.com/setup/deployment/frontend-migration/proxy-setup

NGINX default template

## Proxy setup

It is recommended to run a web proxy behind the frontend and backend for optimized installation.

These urls should be routed to the backend:

```bash theme={null}
/api
/socket
/sitemap.xml
/auth/auth0
/auth/auth0/callback
/auth/logout
```

All other urls should be routed to the frontend.

## Example Config File

This is an example configuration for NGINX. It is also located in the Blockscout repo at [`docker-compose/proxy/default.conf.template`](https://github.com/blockscout/blockscout/blob/master/docker-compose/proxy/default.conf.template)

In this example the frontend and backend are forwarded to port `80`, meaning the new frontend will be available on localhost without needing to specify a port number.

```bash theme={null}
map $http_upgrade $connection_upgrade {

  default upgrade;
  ''      close;
}

server {
    listen       80;
    server_name  localhost;
    proxy_http_version 1.1;

    location ~ ^/(api|socket|sitemap.xml|auth/auth0|auth/auth0/callback|auth/logout) {
        proxy_pass            ${BACK_PROXY_PASS};
        proxy_http_version    1.1;
        proxy_set_header      Host "$host";
        proxy_set_header      X-Real-IP "$remote_addr";
        proxy_set_header      X-Forwarded-For "$proxy_add_x_forwarded_for";
        proxy_set_header      X-Forwarded-Proto "$scheme";
        proxy_set_header      Upgrade "$http_upgrade";
        proxy_set_header      Connection $connection_upgrade;
        proxy_cache_bypass    $http_upgrade;
    }
    location / {
        proxy_pass            ${FRONT_PROXY_PASS};
        proxy_http_version    1.1;
        proxy_set_header      Host "$host";
        proxy_set_header      X-Real-IP "$remote_addr";
        proxy_set_header      X-Forwarded-For "$proxy_add_x_forwarded_for";
        proxy_set_header      X-Forwarded-Proto "$scheme";
        proxy_set_header      Upgrade "$http_upgrade";
        proxy_set_header      Connection $connection_upgrade;
        proxy_cache_bypass    $http_upgrade;
    }
}
server {
    listen       8080;
    server_name  localhost;
    proxy_http_version 1.1;
    proxy_hide_header Access-Control-Allow-Origin;
    proxy_hide_header Access-Control-Allow-Methods;
    add_header 'Access-Control-Allow-Origin' 'http://localhost' always;
    add_header 'Access-Control-Allow-Credentials' 'true' always;
    add_header 'Access-Control-Allow-Methods' 'PUT, GET, POST, OPTIONS, DELETE, PATCH' always;

    location / {
        proxy_pass            http://stats:8050/;
        proxy_http_version    1.1;
        proxy_set_header      Host "$host";
        proxy_set_header      X-Real-IP "$remote_addr";
        proxy_set_header      X-Forwarded-For "$proxy_add_x_forwarded_for";
        proxy_set_header      X-Forwarded-Proto "$scheme";
        proxy_set_header      Upgrade "$http_upgrade";
        proxy_set_header      Connection $connection_upgrade;
        proxy_cache_bypass    $http_upgrade;
    }
}
server {
    listen       8081;
    server_name  localhost;
    proxy_http_version 1.1;
    proxy_hide_header Access-Control-Allow-Origin;
    proxy_hide_header Access-Control-Allow-Methods;
    add_header 'Access-Control-Allow-Origin' 'http://localhost' always;
    add_header 'Access-Control-Allow-Credentials' 'true' always;
    add_header 'Access-Control-Allow-Methods' 'PUT, GET, POST, OPTIONS, DELETE, PATCH' always;
    add_header 'Access-Control-Allow-Headers' 'DNT,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization,x-csrf-token' always;

    location / {
        proxy_pass            http://visualizer:8050/;
        proxy_http_version    1.1;
        proxy_buffering       off;
        proxy_set_header      Host "$host";
        proxy_set_header      X-Real-IP "$remote_addr";
        proxy_connect_timeout 30m;
        proxy_read_timeout    30m;
        proxy_send_timeout    30m;
        proxy_set_header      X-Forwarded-For "$proxy_add_x_forwarded_for";
        proxy_set_header      X-Forwarded-Proto "$scheme";
        proxy_set_header      Upgrade "$http_upgrade";
        proxy_set_header      Connection $connection_upgrade;
        proxy_cache_bypass    $http_upgrade;
        if ($request_method = 'OPTIONS') {
            add_header 'Access-Control-Allow-Origin' 'http://localhost' always;
            add_header 'Access-Control-Allow-Credentials' 'true' always;
            add_header 'Access-Control-Allow-Methods' 'PUT, GET, POST, OPTIONS, DELETE, PATCH' always;
            add_header 'Access-Control-Allow-Headers' 'DNT,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization,x-csrf-token' always;
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'text/plain charset=UTF-8';
            add_header 'Content-Length' 0;
            return 204;
        }
    }
}
```

<Info>
  ***NOTE:*** For production usage you should add at a minimum the correct `server_name` (ie [eth.blockscout.com](http://eth.blockscout.com/)) and TLS info (`ssl_certificate`, `ssl_certificate_key`, `other required variables?`) at a minimum.
</Info>

<Info>
  ***NOTE:*** Here the *stats* service also uses separate port on nginx, but for production usage we recommend a separate hostname for stats. CORS policy for stats should allow the frontend domain.
</Info>


# Separate Frontend
Source: https://docs.blockscout.com/setup/deployment/frontend-migration/separate-frontend



<Tip>
  This option is preferred if you want to modify the UI and/or have more control over the frontend.
</Tip>

<Info>
  You will use the [`external-frontend.yml`](https://github.com/blockscout/blockscout/blob/master/docker-compose/external-frontend.yml) file.
</Info>

## Prerequisites

* Docker v20.10+
* Docker-compose 2.x.x+
* Running Ethereum JSON RPC client

Please see [https://github.com/blockscout/blockscout/tree/master/docker-compose](https://github.com/blockscout/blockscout/tree/master/docker-compose) for additional information

## Migration

### 1) Install frontend separately

Configure the app by passing the necessary environment variables when starting the Docker container.[Information about ENVs is available here](/setup/env-variables/frontend-common-envs).

```sh theme={null}
docker run -p 3000:3000 --env-file <path-to-your-env-file> ghcr.io/blockscout/frontend:latest
```

Alternatively, you can build your own docker image and run your app using that container. Please follow this [guide](https://github.com/blockscout/frontend/blob/main/docs/CUSTOM_BUILD.md).

### 2) Pull changes from the Blockscout master branch

We assume Blockscout is already deployed in your environment.

```sh theme={null}
git pull origin master
```

### 3) Navigate to the docker compose folder

```sh theme={null}
cd docker-compose
```

### 4) Adjust backend envs for your instance

Replace the example environment variables in the `external-frontend.yml` file.

```sh theme={null}
cat external-frontend.yml
```

By default, ENV variables are set to testing settings (anvil) in the `environment:` list. Replace with env vars from your existing backend. The only one you **NEED to keep** is `API_V2_ENABLED='true'` . Any values added here will override existing variables in your instance when you start the container.

```sh theme={null}
environment:
        ETHEREUM_JSONRPC_VARIANT: 'anvil'
        ETHEREUM_JSONRPC_HTTP_URL: http://host.docker.internal:8545/
        ETHEREUM_JSONRPC_WS_URL: ws://host.docker.internal:8545/
        INDEXER_DISABLE_INTERNAL_TRANSACTIONS_FETCHER: 'true'
        INDEXER_DISABLE_PENDING_TRANSACTIONS_FETCHER: 'true'
        DATABASE_URL: postgresql://postgres:@host.docker.internal:7432/blockscout?ssl=false
        ECTO_USE_SSL: 'false'
        SECRET_KEY_BASE: '56NtB48ear7+wMSf0IQuWDAAazhpb31qyc7GiyspBP2vh7t5zlCsF5QDv76chXeN'
        CHAIN_ID: '1337'
        API_V2_ENABLED: 'true'
        MIX_ENV: 'prod'
```

### 5) Run docker compose with FRONT\_PROXY\_PASS variable.

You will pass in the frontend proxy url when running docker compose. The standard configuration for the frontend is `http://host.docker.internal:3000` but if you've made any changes pass in your url.

Run all containers (up) and run processes in the background (-d).

```javascript theme={null}
FRONT_PROXY_PASS=http://host.docker.internal:3000 docker compose -f external-frontend.yml up -d
```

Check progress and view containers:

```sh theme={null}
Docker ps
```

You should see the following containers:

<Frame>
  <img />
</Frame>

### 6) Check the proxy configuration

```sh theme={null}
cd proxy
Cat default.conf.template
```

Unless you overrode the default configs (or did not provide the `FRONT_PROXY_PASS` variable) , you will see the default port for the backend default is 4000, and 3000 for the frontend.

However, with the proxy setup the whole application will default to port 80 (which is just localhost). Your instance should now be served on localhost. [More details about the recommended proxy setup](/setup/deployment/frontend-migration/proxy-setup).

<Info>
  It may take several minutes for the frontend to propagate during this process.
</Info>

### 7) Adjust frontend ENVs if needed

There are several required ENVs for the frontend. If required variables are missing or invalid the frontend will show in error message and will not run the app.

* The common list of [frontend ENVs and descriptions](/setup/env-variables/frontend-common-envs).
* A detailed list with all available ENVs is in the [frontend repo folder.](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md)

To adjust, stop the frontend container, update the env file (or pass variables directly), and restart the container.

### 8) Check Microservice ENVs

Typically the default values will provide what you need for the [`common-visualizer.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-visualizer.env), [`common-stats.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-stats.env), and [`common-smart-contract-verifier.env`](https://github.com/blockscout/blockscout/blob/master/docker-compose/envs/common-smart-contract-verifier.env) files.

Note that in the `smart-contract-verifier.envs` the `SMART_CONTRACT_VERIFIER__SOLIDITY__FETCHER__LIST__LIST_URL` variable is different depending on your OS. The default is Linux, if you are running macOS or Windows be sure to comment out the appropriate variables.


# Kubernetes Deployment
Source: https://docs.blockscout.com/setup/deployment/kubernetes-deployment

Deploy Blockscout using Kubernetes and Helm charts.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [Get Started Now](/using-blockscout/autoscout) and have **your explorer up-and-running in minutes.**
</Tip>

We've released a Helm chart to deploy Blockscout stack ([backend](https://github.com/blockscout/blockscout), [frontend](https://github.com/blockscout/frontend) and [stats](https://github.com/blockscout/blockscout-rs/tree/main/stats)) to a kubernetes cluster.

Baseline instructions are available at [https://github.com/blockscout/helm-charts/tree/main/charts/blockscout-stack](https://github.com/blockscout/helm-charts/tree/main/charts/blockscout-stack).

### Troubleshooting

1. Check your values are correct, for example if you don't have Prometheus installed [disable it here](https://github.com/blockscout/helm-charts/blob/7fe62850a9d0ab220041598722569ab13fa54540/charts/blockscout-stack/values.yaml#L33)
2. Ingress is disabled by default as is common practice, you will likely want to enable ingress and configure hostnames accordingly.
3. Check your .yaml files for any unneeded whitespaces, this can impact functionality.
4. Make sure env variables are declared correctly ie DATABASE\_URL: "X"
5. Frontend values should exist in their own root section, at the same level as blockscout values (and not nested within the blockscout root).

For example:

````bash theme={null}
```yaml
blockscout:
  env:
    DATABASE_URL: "X"
    ETHEREUM_JSONRPC_VARIANT: geth
    ETHEREUM_JSONRPC_HTTP_URL: "X"
    ETHEREUM_JSONRPC_TRACE_URL: "X"
  ingress:
    enabled: true
    hostname: host-name.com
frontend:
  image:
    tag: latest
  ingress:
    enabled: true
````


# Manual Deployment Guide
Source: https://docs.blockscout.com/setup/deployment/manual-deployment-guide

Deploy Blockscout with a user-friendly UI and all microservices

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

<Info>
  📗 This guide walks you through a new Blockscout deployment including the user-friendly UI frontend and installation of all microservices. If you'd prefer a more automated approach see the [docker-compose deployment page](/setup/deployment/docker-compose-deployment).
</Info>

## A. Prerequisites

<Warning>
  Please familiarize yourself with the [general requirements](/setup/requirements/requirements), [db storage requirements](/setup/requirements/database-storage-requirements), [JSON RPC requirements](/setup/requirements/node-tracing-json-rpc-requirements) and [Client setting](/setup/requirements/client-settings) requirements before installing Blockscout.
</Warning>

### Minimum Local Hardware Requirements

* CPU: 4core / 8core
* RAM: 8GB / 16GB / 32GB
* DISK: 120gb or 500GB NVME SSD or Standard SSD
* OS: Linux, MacOS

### Hosting Environment Hardware Requirements

If you are running Blockscout on a cloud server or other remote environment, see the [Hardware and Hosting Requirements](/setup/requirements/resource-requirements)

### Software Dependencies

For Erlang/Elixir, [asdf](https://asdf-vm.com/) is recommended to install and set the appropriate versions. Note the supported versions for Erlang/Elixir/Node are specified in the `.tool-versions` file. Additional Instructions for setting up the environment are available for [Ubuntu](/setup/deployment/manual-deployment-guide/ubuntu-setup) and [MacOS](/setup/deployment/manual-deployment-guide/macos-setup).

| Dependency                                                       | Mac                       | Linux                                                                                                                                                           |
| ---------------------------------------------------------------- | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Erlang/OTP 26](https://github.com/erlang/otp)                   | `brew install erlang`     | [Erlang Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L134)   |
| [Elixir 1.15.x](https://elixir-lang.org/)                        | `brew install elixir`     | [Elixir Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L138)   |
| [Postgres 12, 13, 14](https://www.postgresql.org/)               | `brew install postgresql` | [Postgres Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L187) |
| [Node.js 18.x.x](https://nodejs.org/en/)                         | `brew install node`       | [Node.js Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L66)   |
| [Automake](https://www.gnu.org/software/automake/)               | `brew install automake`   | [Automake Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L72)  |
| [Libtool](https://www.gnu.org/software/libtool/)                 | `brew install libtool`    | [Libtool Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L62)   |
| [Inotify-tools](https://github.com/rvoicilas/inotify-tools/wiki) | Not Required              | Ubuntu - `apt-get install inotify-tools`                                                                                                                        |
| [GCC Compiler](https://gcc.gnu.org/)                             | `brew install gcc`        | [GCC Compiler Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L70)      |
| [GMP](https://gmplib.org/)                                       | `brew install gmp`        | [Install GMP Devel](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L74)         |
| Make                                                             | -                         | `sudo apt install make`if Debian 9                                                                                                                              |
| G++ Compiler                                                     | -                         | `sudo apt install g++`if Debian 9                                                                                                                               |

## B. Manual Deployment

The following guide contains 5 sections that cover a complete Blockscout installation.

1. [Prepare the backend](/setup/deployment/manual-deployment-guide#1.-prepare-the-backend)
2. [Run microservices](/setup/deployment/manual-deployment-guide#2.-run-microservices)
3. [Add the microservices integration to backend](/setup/deployment/manual-deployment-guide#3.-add-the-microservices-integration-to-the-backend)
4. [Run the backend](/setup/deployment/manual-deployment-guide#4.-run-backend)
5. [Run the frontend](/setup/deployment/manual-deployment-guide#5.-run-frontend)

## 1. Prepare the backend

**1)** Clone the repository

`git clone https://github.com/blockscout/blockscout blockscout-backend`

**2)** Change directories

`cd blockscout-backend`

**3)** Provide DB URL with your username `export DATABASE_URL=postgresql://username:password@localhost:5432/blockscout`

* **Linux:** Update the database username and password configuration
* **Mac:** Use logged-in user name and empty password (`export DATABASE_URL=postgresql://username:@localhost:5432/blockscout` )
* **Optional:** Change credentials in `apps/explorer/config/test.exs` for test env *Example usage:* Changing the default Postgres port from localhost:5432 if [Boxen](https://github.com/boxen/boxen) is installed.

<Info>
  You can check the regex pattern for the db url via [https://regex101.com/](https://regex101.com/) with the following regular expression:

  ```
  \w*:\/\/(?<username>[a-zA-Z0-9_-]*):(?<password>[a-zA-Z0-9-*#!%^&$_.]*)?@(?<hostname>(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9])):(?<port>\d+)\/(?<database>[a-zA-Z0-9_-]*)
  ```

  <Frame>
    <img alt="" />
  </Frame>
</Info>

**4)** Install Mix dependencies and compile

`mix do deps.get, local.rebar --force, deps.compile`

**5)** Generate a new secret\_key\_base for the DB

`mix phx.gen.secret`

**6)** Copy keybase and export as an env (for example)

`export SECRET_KEY_BASE=VTIB3uHDNbvrY0+60ZWgUoUBKDn9ppLR8MI4CpRz4/qLyEFs54ktJfaNT6Z221No`

**7)** Export remaining [environment variables](/setup/env-variables) as needed.

CLI basic example:

```cpp theme={null}
export ETHEREUM_JSONRPC_VARIANT=geth
export ETHEREUM_JSONRPC_HTTP_URL=http://localhost:8545
export API_V2_ENABLED=true
export PORT=3001 # set for local API usage
export COIN=yourcoin
export COIN_NAME=yourcoinname
export DISPLAY_TOKEN_ICONS=true
```

**Notes:**

* The `ETHEREUM_JSONRPC_VARIANT` will vary depending on your client (nethermind, geth etc). [More information on client settings](/setup/requirements/client-settings).
* If you're in production environment, please, set `MIX_ENV=prod`. The current default is `MIX_ENV=dev` which is a slower and less secure setting. However, for development purposes, unsetting or setting is `MIX_ENV=dev` is preferred.
* To configure "**My Account**" section on the backend, see [https://docs.blockscout.com/for-developers/configuration-options/my-account-settings](https://docs.blockscout.com/for-developers/configuration-options/my-account-settings)

**8)** Compile the application:

`mix compile`

**9)** If not already running, start Postgres: `pg_ctl -D /usr/local/var/postgres start` or `brew services start postgresql`

<Tip>
  Check [postgres status](https://www.postgresql.org/docs/9.6/app-pg-isready.html): `pg_isready`
</Tip>

**10)** Create and migrate database

`mix do ecto.create, ecto.migrate`

<Warning>
  If you are in dev environment and have run the application previously with a different blockchain, drop the previous database: `mix do ecto.drop, ecto.create, ecto.migrate` Be careful since this will delete all data from the DB. Don't execute it on production if you don't want to lose all of the data!
</Warning>

**11)** Install Node.js dependencies

<Info>
  *Optional: If preferred, use `npm ci` rather than `npm install` to strictly follow all package versions in `package-lock.json.`*
</Info>

`cd apps/block_scout_web/assets; npm install && node_modules/webpack/bin/webpack.js --mode production; cd -`

`cd apps/explorer && npm install; cd -`

`12)` Build static assets for deployment

`mix phx.digest`

**13)** Enable HTTPS in development. The Phoenix server only runs with HTTPS.

`cd apps/block_scout_web; mix phx.gen.cert blockscout blockscout.local; cd -`

**14)** Add blockscout and blockscout.local to your `/etc/hosts`

```
   127.0.0.1       localhost blockscout blockscout.local

   255.255.255.255 broadcasthost

   ::1             localhost blockscout blockscout.local
```

<Info>
  If using Chrome, Enable `chrome://flags/#allow-insecure-localhost`
</Info>

<Tip>
  **🎉 This completes the backend setup! Proceed to setup microservices.**
</Tip>

## 2. Run Microservices

You will use Docker to run 4 Rust microservices: smart-contract verification, smart-contract sol2uml visualizer, sig-provider, and stats services. These add additional functionality to your instance once everything is connected.

### Prerequisites

* Docker v20.10+
* Docker-compose 2.x.x+

### Commands

1. Go to the docker-compose directory
   `cd ./blockscout-backend/docker-compose`
2. run docker-compose
   `docker-compose -f microservices.yml up -d`

### Stats

* Stats will be served from [http://localhost:8080/](http://localhost:8080/)
* You can check, that service works by requesting [http://localhost:8080/health?service=](http://localhost:8080/health?service=). It should return `{"status":"SERVING"}`

### sig-provider

* sig-provider will be at [http://localhost:8083/](http://localhost:8083/)
* You can check, that service works by requesting [http://localhost:8083/health?service=](http://localhost:8083/health?service=). It should return `{"status":"SERVING"}`

### Sc-visualizer

A visualizer for smart contracts.

* sc-visualizer will be located at [http://localhost:8081/](http://localhost:8081/)
* Check the visualizer service works by requesting the [http://localhost:8081/health](http://localhost:8081/health) page - it should return `{"status":"SERVING"}`.

### **Sc-verifier**

A separate smart contract verification service.

* sc-verifier will be at [http://localhost:8082/](http://localhost:8082/).
* Check that the sc-verifier service works by requesting [http://localhost:8082/api/v2/verifier/solidity/versions](http://localhost:8082/api/v2/verifier/solidity/versions) page

<Accordion title="it should return the list of compilers (click to see the sample response)">
  ```
  {"compilerVersions":["v0.8.23+commit.f704f362","v0.8.22+commit.4fc1097e","v0.8.21+commit.d9974bed","v0.8.20+commit.a1b79de6","v0.8.19+commit.7dd6d404","v0.8.18+commit.87f61d96","v0.8.17+commit.8df45f5f","v0.8.16+commit.07a7930e","v0.8.15+commit.e14f2714","v0.8.14+commit.80d49f37","v0.8.13+commit.abaa5c0e","v0.8.12+commit.f00d7308","v0.8.11+commit.d7f03943","v0.8.10+commit.fc410830","v0.8.9+commit.e5eed63a","v0.8.8+commit.dddeac2f","v0.8.7+commit.e28d00a7","v0.8.6+commit.11564f7e","v0.8.5+commit.a4f2e591","v0.8.4+commit.c7e474f2","v0.8.3+commit.8d00100c","v0.8.2+commit.661d1103","v0.8.1+commit.df193b15","v0.8.0+commit.c7dfd78e","v0.7.6+commit.7338295f","v0.7.5+commit.eb77ed08","v0.7.4+commit.3f05b770","v0.7.3+commit.9bfce1f6","v0.7.2+commit.51b20bc0","v0.7.1+commit.f4a555be","v0.7.0+commit.9e61f92b","v0.6.12+commit.27d51765","v0.6.11+commit.5ef660b1","v0.6.10+commit.00c0fcaf","v0.6.9+commit.3e3065ac","v0.6.8+commit.0bbfe453","v0.6.7+commit.b8d736ae","v0.6.6+commit.6c089d02","v0.6.5+commit.f956cc89","v0.6.4+commit.1dca32f3","v0.6.3+commit.8dda9521","v0.6.2+commit.bacdbe57","v0.6.1+commit.e6f7d5a4","v0.6.0+commit.26b70077","v0.5.17+commit.d19bba13","v0.5.16+commit.9c3226ce","v0.5.15+commit.6a57276f","v0.5.14+commit.01f1aaa4","v0.5.13+commit.5b0b510c","v0.5.12+commit.7709ece9","v0.5.11+commit.22be8592","v0.5.10+commit.5a6ea5b1","v0.5.9+commit.c68bc34e","v0.5.8+commit.23d335f2","v0.5.7+commit.6da8b019","v0.5.6+commit.b259423e","v0.5.5+commit.47a71e8f","v0.5.4+commit.9549d8ff","v0.5.3+commit.10d17f24","v0.5.2+commit.1df8f40c","v0.5.1+commit.c8a2cb62","v0.5.0+commit.1d4f565a","v0.4.26+commit.4563c3fc","v0.4.25+commit.59dbf8f1","v0.4.24+commit.e67f0147","v0.4.23+commit.124ca40d","v0.4.22+commit.4cb486ee","v0.4.21+commit.dfe3193c","v0.4.20+commit.3155dd80","v0.4.19+commit.c4cbbb05","v0.4.18+commit.9cf6e910","v0.4.17+commit.bdeb9e52","v0.4.16+commit.d7661dd9","v0.4.15+commit.8b45bddb","v0.4.14+commit.c2215d46","v0.4.13+commit.0fb4cb1a","v0.4.12+commit.194ff033","v0.4.11+commit.68ef5810","v0.4.10+commit.9e8cc01b"]}
  ```
</Accordion>

* You can also use the Blockscout endpoint for smart-contract verification if you prefer (instructions in the integration section)

<Warning>
  To stop all microservices, run `docker-compose -f microservices.yml down`
</Warning>

<Info>
  To troubleshoot issues with a container, run `docker ps` to check which containers are not starting.

  Check logs with `docker logs visualizer -f`
</Info>

## 3. Add the microservices integration to the backend

Add the microservices env variables to the backend. Use the export command to add.

```javascript theme={null}
export MICROSERVICE_SC_VERIFIER_ENABLED=true
export MICROSERVICE_SC_VERIFIER_URL=http://localhost:8082/
export MICROSERVICE_VISUALIZE_SOL2UML_ENABLED=true
export MICROSERVICE_VISUALIZE_SOL2UML_URL=http://localhost:8081/
export MICROSERVICE_SIG_PROVIDER_ENABLED=true
export MICROSERVICE_SIG_PROVIDER_URL=http://localhost:8083/
```

<Info>
  The Blockscout team also provides an endpoint for smart-contract verification. To use, set the following for the `MICROSERVICE_SC_VERIFIER` envs
</Info>

```javascript theme={null}
export MICROSERVICE_SC_VERIFIER_ENABLED=true
export MICROSERVICE_SC_VERIFIER_URL=https://eth-bytecode-db.services.blockscout.com/
export MICROSERVICE_SC_VERIFIER_TYPE=eth_bytecode_db
```

<Tip>
  **🎉 This completes the microservices setup! Proceed to run the backend and frontend.**
</Tip>

## 4. Run backend

1. Return to the blockscout-backend directory `./blockscout-backend`
2. Run `mix phx.server`

The API will be available at [http://localhost:3001/api/](http://localhost:3001/api/)

## 5. Run frontend

The frontend can be added to the same high-level directory as the blockscout-backend or a different directory of your choice.

1. clone the blockscout frontend repository
   `git clone https://github.com/blockscout/frontend blockscout-frontend`

2. change directories

`cd blockscout-frontend`

3. create a .env file, for example

`touch .env`

4. Add this minimal set of required env variables ([additional variables are available here](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md))

```javascript theme={null}
NEXT_PUBLIC_API_HOST=localhost
NEXT_PUBLIC_API_PORT=3001
NEXT_PUBLIC_API_PROTOCOL=http
NEXT_PUBLIC_STATS_API_HOST=http://localhost:8080
NEXT_PUBLIC_VISUALIZE_API_HOST=http://localhost:8081
NEXT_PUBLIC_APP_HOST=localhost
NEXT_PUBLIC_APP_PORT=3000
NEXT_PUBLIC_APP_INSTANCE=localhost
NEXT_PUBLIC_APP_ENV=development
NEXT_PUBLIC_API_WEBSOCKET_PROTOCOL='ws'
NEXT_PUBLIC_WALLET_CONNECT_PROJECT_ID=<your-secret>
```

5. install dependencies

`yarn install`

6. run frontend

`yarn dev`

<Tip>
  **🎉 Once completed, the frontend should be available at `http://localhost:3000`**
</Tip>

**Notes:**

* To configure the **My Account** section, you will add additional env variables on the frontend. See [https://github.com/blockscout/frontend/blob/main/docs/ENVS.md#my-account](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md#my-account)
* More info related to the frontend is available at: [https://github.com/blockscout/frontend/blob/main/docs/CONTRIBUTING.md#local-development](https://github.com/blockscout/frontend/blob/main/docs/CONTRIBUTING.md#local-development)


# MacOS Setup
Source: https://docs.blockscout.com/setup/deployment/manual-deployment-guide/macos-setup



<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

<Info>
  These instructions use homebrew for setup. [Install homebrew](https://docs.brew.sh/Installation) if you don't already have it installed.
</Info>

### 1. Install Requirements

Use homebrew to install basic prerequisites (not including Erlang/Elixir/Node which are installed via asdf)

```sh theme={null}
brew update
brew install node
brew install nvm
brew install automake
brew install libtool
brew install gcc
brew install gmp
```

### 2. Install asdf

[asdf](https://asdf-vm.com/manage/plugins.html) is the easiest way to install and set versioning for Erlang and Elixir.

```sh theme={null}
brew install asdf
asdf plugin add erlang
asdf plugin add elixir
asdf plugin add nodejs
```

### 3. Install and start PostgreSQL-14

```sh theme={null}
brew install postgresql@14
brew services start postgresql@14
```

### 4. Clone the Blockscout repository and install .tool-version from the repository

```sh theme={null}
git clone https://github.com/blockscout/blockscout blockscout-backend
cd blockscout-backend
asdf install
```

Check your elixir version (`elixir -v`) and node version (`node -v`). You should have the following installed:

* `Elixir 1.15.x (compiled with Erlang/OTP 26)`
* `Node v18.17.1`

If there is no response or the proper version is not showing up, you may need to reshim asdf. Please check the [asdf docs](https://asdf-vm.com/) for further info if this doesn't work.

```bash theme={null}
asdf reshim  
export PATH=~/.asdf/shims:$PATH
```

Once complete, recheck your versions and proceed with deployment.

<Tip>
  **🎉 You are ready for manual deployment! **[**Proceed to step 3 in the "Prepare the Backend section**](/setup/deployment/manual-deployment-guide#1.-prepare-the-backend)**"**
</Tip>


# Ubuntu Setup
Source: https://docs.blockscout.com/setup/deployment/manual-deployment-guide/ubuntu-setup



<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

### 1. Install Requirements

1. `sudo apt-get update`

2. `sudo apt-get install inotify-tools && sudo apt install make && sudo apt install g++`

3. `sudo apt-get install libudev-dev zip unzip build-essential cmake -y`

4. `sudo apt-get install git \`<br />`automake \`<br />`libtool inotify-tools \`<br />`libgmp-dev \`<br />`libgmp10 \`<br />`build-essential \`<br />`cmake -y`

### 2. Install ASDF

1. Clone ASDF Plugin

> git clone [https://github.com/asdf-vm/asdf.git](https://github.com/asdf-vm/asdf.git) \~/.asdf

2. Edit your ubuntu profile

> nano .profile

3. add this line in end break

> . \$HOME/.asdf/asdf.sh and ctrl + x (or Save)

4. Refresh your profile after the update

> source \~/.profile

5. Test active asdf after refresh

> asdf version
>
> v0.13.1-fad23bc<br />**Note**: Response following successful install

6. Add asdf plugin for erlang, elixir, and nodejs

> asdf plugin add erlang
>
> asdf plugin add elixir
>
> asdf plugin add nodejs

7. install additional prerequisites

> sudo apt-get -y install build-essential autoconf m4 libncurses5-dev libwxgtk3.0-gtk3-dev libwxgtk-webview3.0-gtk3-dev libgl1-mesa-dev libglu1-mesa-dev libpng-dev libssh-dev unixodbc-dev xsltproc fop libxml2-utils libncurses-dev openjdk-11-jdk

### 3. Install PostgreSQL-14

1. `curl -fsSL https://www.postgresql.org/media/keys/ACCC4CF8.asc|sudo gpg --dearmor -o /etc/apt/trusted.gpg.d/postgresql.gpg`
2. `sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'`
3. `sudo apt update`
4. `sudo apt install postgresql-14`
5. `sudo systemctl status postgresql`

### 4. Add user and database in postgres-14

1. Create user on localpc or server

> adduser dbusername<br />**Note:** Replace dbusername with your username.

2. You will be prompted to create a new profile, just follow the flow.
3. After Adduser now connect to postgres-14

> su - postgres (for Root) or sudo -i -u postgres (for user)

4. Display when entering postgres user section looks like this in terminal

> postgres\@ubuntu:\~\$

5. Create user

> createuser --interactive dbusername

6. Create database

> createdb blockscout

7. connect to psql

> psql

8. Create Password database in dbusername Note

> ALTER USER dbusername WITH PASSWORD 'dbuserpassword';<br />**Note**: Replace dbusername and dbuserpassword that you created

9. Create Privileges on dbusername to database

> GRANT ALL PRIVILEGES ON DATABASE blockscout TO dbusername;
>
> **Note:** Replace dbusername

10. exit psql

> \q

11. Exit to profile postgresql

> postgres\@ubuntu:\~\$ exit

12. Restart postgresql

> sudo systemctl restart postgresql

13. Check new profile that you created at start of adduser replacing dbusername with your username.

> su - dbusername (for Root) or sudo su - dbusername (for user)<br />**Note**: Replace your dbusername

14. Run this command

> psql -d blockscout

15. If everything is correct, you will see this response

> blockscout=#

16. Quit psql

> \q

17. Exit for Database Account page

> dbusername\@ubuntu:\~\$ exit

### 5. Install Rustup / Cargo

After Setup Database, You can Install Rust before installing Blockscout

```sh theme={null}
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
```

### 6. After installing everything, clone the Blockscout repository and install .tool-version from the repository

1. Clone Repository Blockscout

> git clone [https://github.com/blockscout/blockscout](https://github.com/blockscout/blockscout) blockscout-backend

2. Enter to folder clone blockscout

> cd blockscout-backend

3. Install plugin requirements Erlang, Elixir, and Nodejs before install blockscout backend

> asdf install

<Tip>
  **🎉 You are ready for manual deployment!** [**Proceed to step 3 in the "Prepare the Backend section**](/setup/deployment/manual-deployment-guide#1.-prepare-the-backend)**"**
</Tip>


# Manual Deployment (Backend + Old UI)
Source: https://docs.blockscout.com/setup/deployment/manual-old-ui

General deployment instructions for a hardware or cloud services environment

<Warning>
  This method uses the deprecated UI and is not recommended. Please use the [Manual Deployment Guide](/setup/deployment/manual-deployment-guide) to deploy a new version of Blockscout.
</Warning>

## Prepare Environment

Check your environment is prepared with [General Requirements](/setup/requirements/requirements) and [Database Storage Requirements](/setup/requirements/database-storage-requirements).

BlockScout requires a **full archive node** in order to import every state change for every address on the target network. For client specific settings related to a node running Erigon/Geth/Nethermind, please see [Client Settings](/setup/requirements/client-settings).

<Info>
  For testing purposes, instead of an archive node, a test Ethereum client can be used. For instance, [Anvil](https://book.getfoundry.sh/anvil/)
</Info>

## Deployment Steps

**1)** `git clone https://github.com/blockscout/blockscout`

**2)** `cd blockscout`

**3)** Provide DB URL: `export DATABASE_URL=postgresql://user:password@localhost:5432/blockscout`

* **Linux:** Update the database username and password configuration
* **Mac:** Use logged-in user name and empty password
* **Optional:** Change credentials in `apps/explorer/config/test.exs` for test env

<Info>
  *Example usage:* Changing the default Postgres port from localhost:5432 if [Boxen](https://github.com/boxen/boxen) is installed.
</Info>

**4)** Install Mix dependencies and compile them `mix do deps.get, local.rebar --force, deps.compile`

**5)** Generate a new secret\_key\_base for the DB by setting a corresponding ENV var:<br />`export SECRET_KEY_BASE=VTIB3uHDNbvrY0+60ZWgUoUBKDn9ppLR8MI4CpRz4/qLyEFs54ktJfaNT6Z221No`

<Info>
  In order to generate a new `secret_key_base` run `mix phx.gen.secret`
</Info>

**6)** If you have deployed previously, remove static assets from the previous build `mix phx.digest.clean`.

**7)** Set [environment variables](/setup/env-variables) as needed.

CLI Example:

```javascript theme={null}
export ETHEREUM_JSONRPC_VARIANT=nethermind
export ETHEREUM_JSONRPC_HTTP_URL=http://localhost:8545
export DATABASE_URL=postgresql://...
export COIN=DAI
export MIX_ENV=prod
export ... 
```

<Warning>
  It is important to set the variable `MIX_ENV=prod` during deployment. The current default is `MIX_ENV=dev` which is a slower and less secure setting.
</Warning>

<Info>
  The `ETHEREUM_JSONRPC_VARIANT` will vary depending on your client (nethermind, geth etc). [More information on client settings](/setup/requirements/client-settings).
</Info>

**8)** Install and start the[smart contract verification microservice](/setup/microservices/smart-contract-verification). You can [use docker](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier#using-docker), [build from source](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier#building-from-source), or use cargo directly (example below). If you experience issues, see the extensive [smart contract verifier readme](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier/smart-contract-verifier-server#readme).

1. Using docker:
   * `docker run -p 8050:8050 ghcr.io/blockscout/smart-contract-verifier:latest`
2. Or install [rust](https://www.rust-lang.org/tools/install) and build from sources:
   * `cargo install --locked --git https://github.com/blockscout/blockscout-rs smart-contract-verifier-server`
   * Then run the binary as `smart-contract-verifier-server`
3. Set ENV variables in CLI to enable the rust microservice for Blockscout (these can also be set at runtime).

```javascript theme={null}
export MICROSERVICE_SC_VERIFIER_ENABLED=true
export MICROSERVICE_SC_VERIFIER_URL=http://0.0.0.0:8050/
```

**9)** Compile the application:`mix compile`

**10)** If not already running, start Postgres: `pg_ctl -D /usr/local/var/postgres start`

<Tip>
  To check [postgres status](https://www.postgresql.org/docs/9.6/app-pg-isready.html): `pg_isready`
</Tip>

**11)** Create and migrate database `mix do ecto.create, ecto.migrate`

<Warning>
  If you are in dev environment and have run the application previously with a different blockchain, drop the previous database `mix do ecto.drop, ecto.create, ecto.migrate` Be careful since it will delete all data from the DB. Don't execute it on production if you don't want to lose all the data!
</Warning>

**12)** Install Node.js dependencies

<Info>
  *Optional: If preferred, use *`npm ci`* rather than *`npm install`* to strictly follow all package versions in *`package-lock.json`*.*
</Info>

* `cd apps/block_scout_web/assets; npm install && node_modules/webpack/bin/webpack.js --mode production; cd -`
* `cd apps/explorer && npm install; cd -`

**13)** Build static assets for deployment `mix phx.digest`

**14)** Enable HTTPS in development. The Phoenix server only runs with HTTPS.

* `cd apps/block_scout_web; mix phx.gen.cert blockscout blockscout.local; cd -`
* Add blockscout and blockscout.local to your `/etc/hosts`

```
   127.0.0.1       localhost blockscout blockscout.local

   255.255.255.255 broadcasthost

   ::1             localhost blockscout blockscout.local
```

<Info>
  If using Chrome, Enable `chrome://flags/#allow-insecure-localhost`
</Info>

**15)** Return to the root directory and start the Phoenix Server. `mix phx.server`

**16)** Check the [Frontend Migration section](/setup/deployment/frontend-migration) if you would like to connect the enhanced frontend UI to the manually installed backend.

##


# Manual Cleaning An Instance From The Previous Deployment
Source: https://docs.blockscout.com/setup/deployment/manual-old-ui/check-your-manual-deployment-instance



In order to delete build artifacts anyone can run `./rel/commands/clear_build.sh` from the root project directory. It will delete these folders:

* delete `_build` & `deps` directories
* delete node modules located at
* `apps/block_scout_web/assets/node_modules`
* & `apps/explorer/node_modules`
* delete `logs/dev` directory

<Info>
  You should also delete static assets (`apps/block_scout_web/priv/static `folder). Before rebuilding to apply changes to the front-end, run the previous command with `-f` flag:

  `./rel/commands/clear_build.sh -f`
</Info>


# Rollup Deployment
Source: https://docs.blockscout.com/setup/deployment/rollup-deployment

Instructions and environment variables for deploying Blockscout on rollup chains.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click rollup explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [Get Started Now](/using-blockscout/autoscout) and have **your rollup explorer up-and-running in minutes.**
</Tip>

Follow the general [docker](/setup/deployment/docker-compose-deployment) or [manual](/setup/deployment/manual-deployment-guide) instructions for deployment and include additional ENVs (starting with `CHAIN_TYPE`) as rollup deployments require different backend setups depending on the rollup type. Below we provide information and examples for [Arbitrum](/setup/deployment/rollup-deployment#arbitrum) and [Optimism](/setup/deployment/rollup-deployment#optimism).

## Arbitrum

Variables are linked below and supported with `CHAIN_TYPE=arbitrum`. Default values are set for many variables and do not need adjustment for common setups.

<Info>
  Arbitrum environment variables are located here: [https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#arbitrum-management](https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#arbitrum-management)
</Info>

### Example configuration using Ethereum as the settlement layer

```javascript theme={null}
INDEXER_ARBITRUM_ROLLUP_CHUNK_SIZE=20
INDEXER_ARBITRUM_L1_RPC=...
INDEXER_ARBITRUM_L1_RPC_HISTORICAL_BLOCKS_RANGE=1000
INDEXER_ARBITRUM_L1_RPC_CHUNK_SIZE=20
INDEXER_ARBITRUM_L1_ROLLUP_CONTRACT="..." 
INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK=...
INDEXER_ARBITRUM_BRIDGE_MESSAGES_TRACKING_ENABLED="true" //set to true, default will not work
INDEXER_ARBITRUM_MISSED_MESSAGES_RECHECK_INTERVAL=1h
INDEXER_ARBITRUM_TRACKING_MESSAGES_ON_L1_RECHECK_INTERVAL=30s
INDEXER_ARBITRUM_BATCHES_TRACKING_ENABLED="true" //set to true, default will not work
INDEXER_ARBITRUM_BATCHES_TRACKING_RECHECK_INTERVAL=30s
INDEXER_ARBITRUM_NEW_BATCHES_LIMIT=1
INDEXER_ARBITRUM_CONFIRMATIONS_TRACKING_FINALIZED="true"
INDEXER_ARBITRUM_BATCHES_TRACKING_L1_FINALIZATION_CHECK_ENABLED="true"
```

### Arbitrum ENV Notes

#### `INDEXER_ARBITRUM_L1_RPC`

Set to the settlement layer RPC node. In the case above (Ethereum settlement layer) it would be set to your choice of Ethereum RPC nodes such as [https://rpc.ankr.com/eth](https://rpc.ankr.com/eth) or another one of your choice [from this list](https://www.alchemy.com/chain-connect/chain/ethereum). If the rollup settles to a testnet, for example Arbitrum Sepolia, it would be set to [https://arbitrum-sepolia.blockscout.com/](https://arbitrum-sepolia.blockscout.com/) ( [info retrieved here](https://docs.arbitrum.io/build-decentralized-apps/reference/node-providers))

#### `INDEXER_ARBITRUM_L1_ROLLUP_CONTRACT`

The rollup contract address is output during the contract deployment process (check the `OutputInfo.json` file in the main directory of your script folder). **The rollup contract address must be added** as there is no default value for this variable. If using a RaaS for deployment the service may provide this output. For example, Gelato provides a list of contracts on deployment, and you can copy the value from their dashboard.

<Frame>
  <img alt="" />
</Frame>

#### `INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK`

<Tip>
  You can also use the [Blockscout MCP](/devs/mcp-server) to find values for the `ROLLUP_INIT_BLOCK and RPC_HISTORICAL_BLOCKS_RANGE. `[See this example.](/devs/mcp-examples/rollup-deployment-variables)
</Tip>

Get this value using the block explorer for the settlement layer chain. Search the rollup contract address and find the transaction and block where the contract was deployed. Use that block number as the value for this env.

<Frame>
  <img alt="" />
</Frame>

<Frame>
  <img alt="" />
</Frame>

#### `INDEXER_ARBITRUM_L1_RPC_HISTORICAL_BLOCKS_RANGE`

The RPC historical blocks range depends on the following factors:

1. Block production rate for the settlement layer.
2. L1 RPC node limits. Specifically, the maximum block range for the `eth_getLogs` operation is needed. This can be identified empirically or by contacting the node admin.
3. Batch production rate for the rollup. To check this you will look at the `SequencerInbox` contract. To find the contract address, go the `Rollup` contract in the block explorer, go to read methods (or read proxy), and find the `SequencerInbox` method. This will display the address of the contract.

<Frame>
  <img alt="" />
</Frame>

<Frame>
  <img alt="" />
</Frame>

* Batch production rate can be identified by looking at how fast the `SequencerInbox` contract is called with the method `addSequencerL2BatchFromOrigin`. Transactions to the contract can be found on the contract page of the block explorer.

<Frame>
  <img alt="" />
</Frame>

**Recommendations based on these factors:**

1. If the block production rate on the settlement layer is low (like one block per 12 secs for Ethereum Mainnet), choose a block range that covers 1 or 2 batches.
2. If the block production rate is high (if another rollup is used as a settlement layer), look at the minimum amount of settlement layer blocks produced during the time required to produce 2 rollup batches and the block range limit to retrieve logs from the L1 RPC node. For example, if 5000 settlement layer blocks are produced during the time when two subsequent batches are sent to the settlement layer and the RPC node block range limit is 3000, the smaller 3000 value should be used.

#### `INDEXER_ARBITRUM_BATCHES_TRACKING_RECHECK_INTERVAL` & `INDEXER_ARBITRUM_TRACKING_MESSAGES_ON_L1_RECHECK_INTERVAL`

Tracking intervals depend on the block production rate on the settlement layer. Do not set them lower than the average block time. Higher values will cause latency in batches/messages identification. The default for L1 batches and messages re-check is 20 seconds.

#### `INDEXER_ARBITRUM_ROLLUP_CHUNK_SIZE & INDEXER_ARBITRUM_L1_RPC_CHUNK_SIZE`

Chunk sizes depend on the RPC nodes' rate limits. Larger chunks may cause rate limit errors and smaller chunks introduce additional network-related delays.`INDEXER_ARBITRUM_ROLLUP_CHUNK_SIZE` configures the chunk size for the rollup RPC node and`INDEXER_ARBITRUM_L1_RPC_CHUNK_SIZE` configures the chunk size for the settlement layer (L1) RPC node.

#### `INDEXER_ARBITRUM_BATCHES_TRACKING_MESSAGES_TO_BLOCKS_SHIFT`

<Warning>
  The only chain identified so far where this variable is required is the **Arbitrum One** chain.
</Warning>

This variable must be configured for chains where the message counters in the call `addSequencerL2BatchFromOrigin` of the `SequencerInbox` contract do not correspond directly to the rollup block numbers.

#### `INDEXER_ARBITRUM_BATCHES_TRACKING_ENABLED` & `INDEXER_ARBITRUM_BRIDGE_MESSAGES_TRACKING_ENABLED`

The default for these variables will not run the corresponding fetchers, so they need to be set to "true".

## Optimism

Variables are linked below and supported with `CHAIN_TYPE=optimism.` Default values are set for many variables and typically do not need adjustment for common setups.

<Info>
  Optimism environment variables are located here: [https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#optimism-rollup-management](https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#optimism-rollup-management)
</Info>

Example configuration using Ethereum as the settlement layer (includes defaults)

```bash theme={null}
INDEXER_OPTIMISM_L1_RPC=...
INDEXER_OPTIMISM_L1_SYSTEM_CONFIG_CONTRACT=...
INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL=https://eth.blockscout.com/api/v2/blobs
INDEXER_OPTIMISM_L1_BATCH_CELESTIA_BLOBS_API_URL=...
INDEXER_OPTIMISM_L1_BATCH_BLOCKS_CHUNK_SIZE=4
INDEXER_OPTIMISM_L2_BATCH_GENESIS_BLOCK_NUMBER=0
INDEXER_OPTIMISM_L1_OUTPUT_ORACLE_CONTRACT=... //omit if FaultProofs upgrade is on chain
INDEXER_OPTIMISM_L1_DEPOSITS_BATCH_SIZE=500
INDEXER_OPTIMISM_L1_DEPOSITS_TRANSACTION_TYPE=126
INDEXER_OPTIMISM_L2_WITHDRAWALS_START_BLOCK=1
INDEXER_OPTIMISM_L2_MESSAGE_PASSER_CONTRACT=0x4200000000000000000000000000000000000016

//required if INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL is set
INDEXER_BEACON_RPC_URL=...
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT=8500000
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP=1708824023
INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION=12
```

### Optimism ENV Notes

#### `INDEXER_OPTIMISM_L1_SYSTEM_CONFIG_CONTRACT`

Address of SystemConfig smart contract that contains most of the configuration parameters used by the OP fetcher modules. The address is usually found in the chain's online docs. If there are no docs available, ask the chain's team for the SystemConfig contract address.

#### `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL`

If the OP chain uses EIP-4844 blobs as data storage, this env is required. If this is the case, the following envs must also be defined:

* `INDEXER_BEACON_RPC_URL`
* `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT`
* `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP`
* `INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION`

These envs are used by the batch indexing module as a fallback source of blob data and for retrieving the blob data in realtime from L1. These values should be used for the following L1s. If clarification is needed please contact the Blockscout team.

```javascript theme={null}
// Ethereum Mainnet
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT=8500000
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP=1708824023
INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION=12

// Sepolia
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT=4400000
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP=1708533600
INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION=12

// Holesky
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT=1000000
INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP=1707902400
INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION=12
```

#### `INDEXER_OPTIMISM_L2_BATCH_GENESIS_BLOCK_NUMBER`

Typically found in the [superchain registry](https://github.com/ethereum-optimism/superchain-registry/blob/main/superchain/configs/configs.json) in superchains.chains\[i].genesis.l2.number, e.g. for OP Mainnet it is `105235063`. For most new OP chains the value will be `0` as these chains start with the BedRock upgrade activated from scratch.

#### `INDEXER_OPTIMISM_L1_OUTPUT_ORACLE_CONTRACT`

This contract's address can be found in chain's online docs. If there are no docs available, contact the chain for this information. This address is not needed (and can be omitted) for OP chains that started with the [FaultProofs upgrade](https://docs.optimism.io/stack/protocol/fault-proofs/explainer) activated from the genesis block.


# Terraform Deployment
Source: https://docs.blockscout.com/setup/deployment/terraform-deployment

Supernets deployment configs

Terraform config files are currently available for Polygon supernets deployment. Settings can be updated based on client infrastructure.

Examples include deployment for a new Virtual Private Cloud (VPC) instance and deployment within an existing VPC, where ec2 instances, database, security groups and load balancers are added to existing infrastructure.

<Card title="GitHub - blockscout/terraform-for-supernet" icon="github" href="https://github.com/blockscout/terraform-for-supernet" icon="cloud">
  GitHub
</Card>


# Upgrade Guide (V7.0 & V8.0)
Source: https://docs.blockscout.com/setup/deployment/upgrade-guide-v7-0

Guide for upgrading Blockscout to major versions 7.0 and 8.0.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [Get Started Now](/using-blockscout/autoscout) and have **your explorer up-and-running in minutes.**
</Tip>

<Info>
  We continue to add new features and functionality to Blockscout and recommend updating your instance with each new release. You can check compatibility between your current backend and frontend versions in the [Compatibility Matrix](/setup/requirements/back-front-compatibility-matrix).
</Info>

<Warning>
  If it has been a while since your last upgrade, we recommend performing incremental upgrades to ensure proper performance. For example if you are running backend v6.9.0, first upgrade to v6.10.0 prior to upgrading to the [latest 7.0 version](https://github.com/blockscout/blockscout/releases). This reduces downtime and ensures all breaking changes are handled. Please update to v7.0 before updating to v8.0. Follow the same process below replacing v7 with the latest front and backend repositories.
</Warning>

## Getting Started

<Tip>
  This guide walks through the process of updating Blockscout to backend v7.0.2 and frontend v1.38.0 (March, 2025) from v6.10.X. If you have questions about a different upgrade, [contact us in Discord](https://discord.gg/blockscout). Breaking changes follow the instructions.
</Tip>

### 1) Update backend ENV variables

<Warning>
  Backend variable renaming only applies to the 6.10.X -> 7.0.X update. If you are performing a more extensive update, please check renaming & deprecations from the release notes of every minor release (6.8.0, 6.9.0 etc) within your update range.
</Warning>

Newly renamed variables include the `MIGRATION`prefix. If a variable contained `MIGRATION` in the name previously, it has been moved to the beginning of the variable. Expand below to see all variables you need to rename.

<Accordion title="Backend Renamed Variables">
  | Old name                                                       | New name                                                        |
  | -------------------------------------------------------------- | --------------------------------------------------------------- |
  | TOKEN\_ID\_MIGRATION\_FIRST\_BLOCK                             | MIGRATION\_TOKEN\_ID\_FIRST\_BLOCK                              |
  | TOKEN\_ID\_MIGRATION\_CONCURRENCY                              | MIGRATION\_TOKEN\_ID\_CONCURRENCY                               |
  | TOKEN\_ID\_MIGRATION\_BATCH\_SIZE                              | MIGRATION\_TOKEN\_ID\_BATCH\_SIZE                               |
  | SHRINK\_INTERNAL\_TRANSACTIONS\_BATCH\_SIZE                    | MIGRATION\_SHRINK\_INTERNAL\_TRANSACTIONS\_BATCH\_SIZE          |
  | SHRINK\_INTERNAL\_TRANSACTIONS\_CONCURRENCY                    | MIGRATION\_SHRINK\_INTERNAL\_TRANSACTIONS\_CONCURRENCY          |
  | TOKEN\_INSTANCE\_OWNER\_MIGRATION\_CONCURRENCY                 | MIGRATION\_TOKEN\_INSTANCE\_OWNER\_CONCURRENCY                  |
  | TOKEN\_INSTANCE\_OWNER\_MIGRATION\_BATCH\_SIZE                 | MIGRATION\_TOKEN\_INSTANCE\_OWNER\_BATCH\_SIZE                  |
  | TOKEN\_INSTANCE\_OWNER\_MIGRATION\_ENABLED                     | MIGRATION\_TOKEN\_INSTANCE\_OWNER\_ENABLED                      |
  | DENORMALIZATION\_MIGRATION\_BATCH\_SIZE                        | MIGRATION\_DENORMALIZATION\_BATCH\_SIZE                         |
  | DENORMALIZATION\_MIGRATION\_CONCURRENCY                        | MIGRATION\_DENORMALIZATION\_CONCURRENCY                         |
  | TOKEN\_TRANSFER\_TOKEN\_TYPE\_MIGRATION\_BATCH\_SIZE           | MIGRATION\_TOKEN\_TRANSFER\_TOKEN\_TYPE\_BATCH\_SIZE            |
  | TOKEN\_TRANSFER\_TOKEN\_TYPE\_MIGRATION\_CONCURRENCY           | MIGRATION\_TOKEN\_TRANSFER\_TOKEN\_TYPE\_CONCURRENCY            |
  | SANITIZE\_INCORRECT\_NFT\_BATCH\_SIZE                          | MIGRATION\_SANITIZE\_INCORRECT\_NFT\_BATCH\_SIZE                |
  | SANITIZE\_INCORRECT\_NFT\_CONCURRENCY                          | MIGRATION\_SANITIZE\_INCORRECT\_NFT\_CONCURRENCY                |
  | SANITIZE\_INCORRECT\_NFT\_TIMEOUT                              | MIGRATION\_SANITIZE\_INCORRECT\_NFT\_TIMEOUT                    |
  | SANITIZE\_INCORRECT\_WETH\_BATCH\_SIZE                         | MIGRATION\_SANITIZE\_INCORRECT\_WETH\_BATCH\_SIZE               |
  | SANITIZE\_INCORRECT\_WETH\_CONCURRENCY                         | MIGRATION\_SANITIZE\_INCORRECT\_WETH\_CONCURRENCY               |
  | SANITIZE\_INCORRECT\_WETH\_TIMEOUT                             | MIGRATION\_SANITIZE\_INCORRECT\_WETH\_TIMEOUT                   |
  | REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_BATCH\_SIZE           | MIGRATION\_REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_BATCH\_SIZE |
  | REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_CONCURRENCY           | MIGRATION\_REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_CONCURRENCY |
  | REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_TIMEOUT               | MIGRATION\_REINDEX\_INTERNAL\_TRANSACTIONS\_STATUS\_TIMEOUT     |
  | FILECOIN\_PENDING\_ADDRESS\_OPERATIONS\_MIGRATION\_BATCH\_SIZE | MIGRATION\_FILECOIN\_PENDING\_ADDRESS\_OPERATIONS\_BATCH\_SIZE  |
  | FILECOIN\_PENDING\_ADDRESS\_OPERATIONS\_MIGRATION\_CONCURRENCY | MIGRATION\_FILECOIN\_PENDING\_ADDRESS\_OPERATIONS\_CONCURRENCY  |
  | ARBITRUM\_DA\_RECORDS\_NORMALIZATION\_MIGRATION\_BATCH\_SIZE   | MIGRATION\_ARBITRUM\_DA\_RECORDS\_NORMALIZATION\_BATCH\_SIZE    |
  | ARBITRUM\_DA\_RECORDS\_NORMALIZATION\_MIGRATION\_CONCURRENCY   | MIGRATION\_ARBITRUM\_DA\_RECORDS\_NORMALIZATION\_CONCURRENCY    |
</Accordion>

### 2) Install backend

-> [blockscout/blockscout:7.0.2](https://hub.docker.com/layers/blockscout/blockscout/7.0.2/images/sha256-b846205631b5bf525022c7d15d076fe0fcbf627e00e03b8285aeccffed3ad145)

### 3) Install frontend

-> [ghcr.io/blockscout/frontend:v1.38.0](https://github.com/blockscout/frontend/pkgs/container/frontend/365117431?tag=v1.38.0)

<Accordion title="Frontend Variable Updates">
  | From                                                                                 | To                                           | Example                                                                                                                                                                                                                                                 |
  | ------------------------------------------------------------------------------------ | -------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
  | NEXT\_PUBLIC\_ROLLUP\_L1\_BASE\_URL NEXT\_PUBLIC\_ROLLUP\_PARENT\_CHAIN\_NAME        | NEXT\_PUBLIC\_ROLLUP\_PARENT\_CHAIN          | current values `NEXT_PUBLIC_ROLLUP_L1_BASE_URL =<L1-url>` `NEXT_PUBLIC_ROLLUP_PARENT_CHAIN_NAME =<chain-name>`new values `NEXT_PUBLIC_ROLLUP_PARENT_CHAIN={'name':'<chain-name>','baseUrl':'<L1-url>'}`                                                 |
  | NEXT\_PUBLIC\_RE\_CAPTCHA\_V3\_APP\_SITE\_KEY                                        | NEXT\_PUBLIC\_RE\_CAPTCHA\_APP\_SITE\_KEY    |                                                                                                                                                                                                                                                         |
  | NEXT\_PUBLIC\_HOMEPAGE\_PLATE\_TEXT\_COLOR NEXT\_PUBLIC\_HOMEPAGE\_PLATE\_BACKGROUND | NEXT\_PUBLIC\_HOMEPAGE\_HERO\_BANNER\_CONFIG | current values `NEXT_PUBLIC_HOMEPAGE_PLATE_BACKGROUND=<my-background>` `NEXT_PUBLIC_HOMEPAGE_PLATE_TEXT_COLOR=<my-text-color>` new values `NEXT_PUBLIC_HOMEPAGE_HERO_BANNER_CONFIG={'background':['<my-background>'],'text_color':['<my-text-color>']}` |

  **Deprecated Frontend Variables**

  | Deprecated                            |
  | ------------------------------------- |
  | NEXT\_PUBLIC\_AUTH0\_CLIENT\_ID       |
  | NEXT\_PUBLIC\_AUTH\_URL               |
  | NEXT\_PUBLIC\_LOGOUT\_URL             |
  | FAVICON\_GENERATOR\_API\_KEY          |
  | NEXT\_PUBLIC\_SENTRY\_DSN             |
  | SENTRY\_CSP\_REPORT\_URI              |
  | NEXT\_PUBLIC\_SENTRY\_ENABLE\_TRACING |
</Accordion>

### 4) Install microservices

-> Stats microservice [ghcr.io/blockscout/stats:v2.5.0](https://github.com/blockscout/blockscout-rs/pkgs/container/stats/353347284?tag=v2.5.0).

-> Use the `latest` tag to install any other microservices used with your instance [https://github.com/blockscout/blockscout-rs](https://github.com/blockscout/blockscout-rs)

## Breaking Changes

<Warning>
  `/api/v1/health`, `/api/v1/health/liveness`, `/api/v1/health/readiness` have been removed in favor of `/api/health/**` endpoints.
</Warning>

<Warning>
  `/api/v2/addresses/:address_hash` returns 200 instead 404 for valid hashes which are not in the DB.
</Warning>

<Warning>
  `/api/v2/tokens/:token_hash/instances` owner's ens\_domain\_name property now preloads the ens domain name.
</Warning>

<Warning>
  transaction hash and address hash are no longer mandatory in the `txlistinternal` API v1 endpoint
</Warning>

<Warning>
  `/metrics` endpoint available on indexer pod (previously existed only on API pod)
</Warning>


# ENV Variables
Source: https://docs.blockscout.com/setup/env-variables

Environment variables for configuring Blockscout instances.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

Blockscout uses ENVs for setting hundreds of different parameters. Please see the various sections for ENV names, descriptions, default values and versioning.

<Info>
  * [Backend ENVs: Common](/setup/env-variables/backend-env-variables)
  * [Backend ENVs: Chain Specific](/setup/env-variables/backend-envs-chain-specific)
  * [Backend ENVs: Integrations](/setup/env-variables/backend-envs-integrations)
  * [Frontend ENVs: Common](/setup/env-variables/frontend-common-envs)
</Info>

<Warning>
  You will find deprecated ENV vars on the [Deprecated ENV Variables](https://docs.blockscout.com/for-developers/information-and-settings/deprecated-env-variables) page.
</Warning>

## Set ENV Variables with CLI

Use the export command to set variables. For example:

```javascript theme={null}
$ export ETHEREUM_JSONRPC_VARIANT=nethermind
$ export COIN=POA
$ export NETWORK=POA
```

## Required ENV variables

Please see the [Backend ENVs page](/setup/env-variables/backend-env-variables) for details. Required variables are located in the General Management section and marked with a ✅

## Example ENV Variables Set

The following variables are set for the [Gnosis Chain Blockscout Instance](https://gnosis.blockscout.com/). *Note that some variables are not included as they contain private information which should not be exposed.*

<Card title="Gnosis-Chain-Variables.txt" icon="file-arrow-down" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2Fgit-blob-6ca29409491d82049d08c1b49886487cc8960e65%2FGnosis-Chain-Variables.txt?alt=media">
  6KB
</Card>

## Time format

Can be set in format `1h` for 1 hour, `1m` for 1 minute, `1s` or `1` for 1 second, `1ms` for 1 millisecond

<Warning>
  *Note*: **Before release 5.1.2, all environment variables of time format supported only integers in seconds (without dimensions) as values.**
</Warning>


# Backend ENVs: Common
Source: https://docs.blockscout.com/setup/env-variables/backend-env-variables



### Categories

<CardGroup>
  <Card>
    [Required variables](/setup/env-variables/backend-env-variables#required-variables)

    [General Management](/setup/env-variables/backend-env-variables#general-management)

    [Database Management](/setup/env-variables/backend-env-variables#database-management)
  </Card>

  <Card>
    [JSON RPC Node Management](/setup/env-variables/backend-env-variables#json-rpc-node-management)

    [Indexer Management](/setup/env-variables/backend-env-variables#indexer-management)

    [DB Migrations & Sanitizer Management](/setup/env-variables/backend-env-variables#db-migrations-and-sanitizer-management)
  </Card>

  <Card>
    [Market](/setup/env-variables/backend-env-variables#market)

    [Cache Management](/setup/env-variables/backend-env-variables#cache-management)

    [Gas Price Oracle](/setup/env-variables/backend-env-variables#gas-price-oracle)
  </Card>

  <Card>
    [Main Page Dashboard](/setup/env-variables/backend-env-variables#main-page-dashboard)

    [Contract Management](/setup/env-variables/backend-env-variables#contract-management)

    [Bridged Tokens](/setup/env-variables/backend-env-variables#bridged-tokens)
  </Card>

  <Card>
    [Miscellaneous UI](/setup/env-variables/backend-env-variables#miscellaneous-ui)

    [CSV Export](/setup/env-variables/backend-env-variables#csv-export)

    [reCAPTCHA](/setup/env-variables/backend-env-variables#recaptcha)
  </Card>

  <Card>
    [API Rate Limits](/setup/env-variables/backend-env-variables#api-rate-limits)

    [General application rate Limits](/setup/env-variables/backend-env-variables#general-application-rate-limits)

    [GraphQL API](/setup/env-variables/backend-env-variables#graphql-api)
  </Card>

  <Card>
    [Account Related](/setup/env-variables/backend-env-variables#account-related)

    [Specific Smart Contracts](/setup/env-variables/backend-env-variables#specific-smart-contracts)

    [CDN](/setup/env-variables/backend-env-variables#cdn)
  </Card>

  <Card>
    [Addresses Blacklist management](/setup/env-variables/backend-env-variables#addresses-blacklist-management)

    [Prometheus Metrics Management](/setup/env-variables/backend-env-variables#prometheus-metrics-management)

    [Backend ENVs: Chain-Specific](/setup/env-variables/backend-envs-chain-specific)
  </Card>

  <Card>
    [Backend ENVs: Integrations](/setup/env-variables/backend-envs-integrations)

    [Old UI Management](/setup/env-variables/old-ui-management)

    [Old UI Management: Header and Footer](/setup/env-variables/backend-env-variables#header-and-footer)
  </Card>
</CardGroup>

## Time format

Can be set in format `1h` for 1 hour, `1m` for 1 minute, `1s` or `1` for 1 second, `1ms` for 1 millisecond

<Warning>
  ***Note*** **: Before release 5.1.2, all environment variables of time format supported only integers in seconds (without dimensions) as values.**
</Warning>

## Required variables

| Variable                    | Description                                                                                                                                                                       | Parameters                                                                                      |
| --------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------- |
| `ETHEREUM_JSONRPC_VARIANT`  | Tells the application which RPC Client the node is using (i.e. `erigon`, `geth`, `nethermind`, `besu`, `filecoin`, or `anvil`) (See Client Settings for more info)                | Required: ✅ <br />Version: All <br />Default: `geth` <br />Applications: API, Indexer           |
| `ETHEREUM_JSONRPC_HTTP_URL` | The RPC endpoint used to fetch blocks, transactions, receipts, tokens.                                                                                                            | Required: ✅ <br />Version: All <br />Default: `localhost:8545` <br />Applications: API, Indexer |
| `DATABASE_URL`              | Defines the Postgres Database endpoint.                                                                                                                                           | Required: ✅ <br />Version: All <br />Default: (empty) <br />Applications: API, Indexer          |
| `SECRET_KEY_BASE`           | The value used to [sign cookies](https://hexdocs.pm/plug/Plug.Session.COOKIE.html). Use mix phx.gen.secret to generate a new Secret Key Base string to protect production assets. | Required: ✅ <br />Version: All <br />Default: (empty) <br />Applications: API                   |

## General Management

| Variable                                                | Description                                                                                                                                                                                                                                                                                                                                                                                                                                        | Parameters                                                                                                                                                                                                                                                                                                                                                                            |
| ------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `APPLICATION_MODE`                                      | Defines the current application mode. Available values are: `all`, `indexer`, `api`. Implemented in [#10631](https://github.com/blockscout/blockscout/pull/10631).                                                                                                                                                                                                                                                                                 | Version: v6.8.0+ <br />Default: `all` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                |
| `DISABLE_FILE_LOGGING`                                  | Disables file-based logging when set to `true`. When enabled, application logs will only be written to stdout/stderr.                                                                                                                                                                                                                                                                                                                              | Version: v9.1.0+ <br />Default: `false` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |
| `SECRET_KEY_BASE`                                       | The value used to [sign cookies](https://hexdocs.pm/plug/Plug.Session.COOKIE.html). Use mix phx.gen.secret to generate a new Secret Key Base string to protect production assets.                                                                                                                                                                                                                                                                  | Required: ✅ <br />Version: All <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                         |
| `NETWORK_PATH`                                          | Used to set a network path other than what is displayed in the root directory. An example would be to add `/eth/mainnet/` to the root directory.                                                                                                                                                                                                                                                                                                   | Version: All <br />Default: `/` <br />Applications: API                                                                                                                                                                                                                                                                                                                               |
| `BLOCKSCOUT_HOST`                                       | Host for API endpoint examples.                                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v2.1.0+ <br />Default: `localhost` <br />Applications: API                                                                                                                                                                                                                                                                                                                   |
| `BLOCKSCOUT_PROTOCOL`                                   | Url scheme for blockscout.                                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v2.1.0+ <br />Default: prod env `https`, dev env `http` <br />Applications: API                                                                                                                                                                                                                                                                                              |
| `CHECK_ORIGIN`                                          | Used to check the origin of requests when the origin header is present. It defaults to `false`. In case of true, it will check against the host value.                                                                                                                                                                                                                                                                                             | Version: All <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                                                           |
| `PORT`                                                  | Default port the application runs on is 4000.                                                                                                                                                                                                                                                                                                                                                                                                      | Version: All <br />Default: `4000` <br />Applications: API                                                                                                                                                                                                                                                                                                                            |
| `COIN`                                                  | Coin is checked via the CoinGecko API to obtain USD prices on graphs and other areas of the UI.                                                                                                                                                                                                                                                                                                                                                    | Version: All <br />Default: `POA` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                    |
| `COIN_NAME`                                             | Displayed name of the coin. Also used for "Add chain to MetaMask" button and for Account functionality as native coin name in the email letters for watch list.                                                                                                                                                                                                                                                                                    | Version: v4.1.2+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `EMISSION_FORMAT`                                       | Should be set to `POA` if you have block emission identical to POA Network. This env var is used only if `CHAIN_SPEC_PATH` is set.                                                                                                                                                                                                                                                                                                                 | Version: v2.0.4+ <br />Default: `DEFAULT` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                            |
| `CHAIN_SPEC_PATH`                                       | Chain specification path (absolute file system path or URL) to import block emission reward ranges and genesis account balances from. Geth- and OpenEthereum-style specs are supported.                                                                                                                                                                                                                                                            | Version: v2.0.4+ <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |
| `CHAIN_SPEC_PROCESSING_DELAY`                           | Chain specification path processing delay. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11874](https://github.com/blockscout/blockscout/pull/11874).                                                                                                                                                                                                                                                    | Version: v7.0.0+ <br />Default: 15s <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                  |
| `PRECOMPILED_CONTRACTS_CONFIG_PATH`                     | Precompiled contracts description path (absolute file system path or URL) to import ABI and source code of the precompiled contracts.                                                                                                                                                                                                                                                                                                              | Version: v6.5.0+ <br />Default: (empty) or `/app/config/assets/precompiles-arbitrum.json` for `arbitrum` chaintype <br />Applications: API, Indexer                                                                                                                                                                                                                                   |
| `SUPPLY_MODULE`                                         | Used by RSK in order to tell the application how to calculate the total supply of the chain. Available value is `RSK`                                                                                                                                                                                                                                                                                                                              | Version: All <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                  |
| `HEART_BEAT_TIMEOUT`                                    | Production environment variable to restart the application in the event of a crash.                                                                                                                                                                                                                                                                                                                                                                | Version: All <br />Default: `30` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                     |
| `HEART_COMMAND`                                         | Production environment variable to restart the application in the event of a crash.                                                                                                                                                                                                                                                                                                                                                                | Version: All <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                  |
| `ELIXIR_VERSION`                                        | Elixir version to install on the node before Blockscout deploy. It is used in bash script in Terraform / Ansible deployment script                                                                                                                                                                                                                                                                                                                 | Version: All <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                  |
| `DISABLE_WEBAPP`                                        | If `true` endpoints to webapp are hidden. Also, enabling it makes notifications go through `db_notify`                                                                                                                                                                                                                                                                                                                                             | Needs Recompile: ☑️ Version: v2.0.3+ <br />Default: `false` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                          |
| `API_V1_READ_METHODS_DISABLED`                          | If `true`, read-only endpoints to API v1 are hidden.                                                                                                                                                                                                                                                                                                                                                                                               | Needs Recompile: ☑️ Version: v5.1.5+ <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                                   |
| `API_V1_WRITE_METHODS_DISABLED`                         | If `true`, write endpoints to API v1 are hidden.                                                                                                                                                                                                                                                                                                                                                                                                   | Needs Recompile: ☑️ Version: v5.1.5+ <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                                   |
| `DISABLE_API`                                           | If `true`, endpoint is not started. Set this if you want to use an indexer-only setup. Implemented in [#10032](https://github.com/blockscout/blockscout/pull/10032)                                                                                                                                                                                                                                                                                | Version: v6.6.0+ <br />Default: `false` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |
| `WEBAPP_URL`                                            | Link to web application instance, e.g. `protocol://host/path`                                                                                                                                                                                                                                                                                                                                                                                      | Version: v2.0.3+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `API_URL`                                               | Link to API instance, e.g. `protocol://host/path`                                                                                                                                                                                                                                                                                                                                                                                                  | Version: v2.0.3+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `API_V2_ENABLED`                                        | Enable API V2. Implemented in [#6361](https://github.com/blockscout/blockscout/pull/6361) (v5.0.0+), default `true` since [#8802](https://github.com/blockscout/blockscout/pull/8802)                                                                                                                                                                                                                                                              | Version: v5.3.2+ <br />Default: `true` <br />Applications: API                                                                                                                                                                                                                                                                                                                        |
| `API_SENSITIVE_ENDPOINTS_KEY`                           | API key to protect some sensitive endpoints. Implemented in [#7355](https://github.com/blockscout/blockscout/pull/7355)                                                                                                                                                                                                                                                                                                                            | Version: v5.1.5+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `CHECKSUM_ADDRESS_HASHES`                               | If set to `true`, redirects to checksummed version of address hashes.                                                                                                                                                                                                                                                                                                                                                                              | Version: v3.1.0+ <br />Default: `true` <br />Applications: API                                                                                                                                                                                                                                                                                                                        |
| `CHECKSUM_FUNCTION`                                     | Defines checksum address function. 2 available values: `rsk`, `eth`                                                                                                                                                                                                                                                                                                                                                                                | Version: v2.0.1+ <br />Default: `eth` <br />Applications: API                                                                                                                                                                                                                                                                                                                         |
| `CHAIN_TYPE`                                            | Specifies the blockchain architecture and enables chain-specific data models and fetchers.                                                                                                                                                                                                                                                                                                                                                         | Runtime configurable (v8.0.0+): `neon`, `stability`, `blackfort`, `shibarium`, `arc` <br />Needs recompilation: `ethereum`, `optimism`, `arbitrum`, `optimism-celo` (formerly `celo` before v9.3.0), `polygon_zkevm`, `rsk`, `suave`, `zetachain`, `filecoin`, `zilliqa`, and other values prior to v8.0.0 Version: v5.3.0+ <br />Default: `default` <br />Applications: API, Indexer |
| `CHAIN_ID`                                              | Chain ID of the network. For instance, 100 in the case of xDai chain.                                                                                                                                                                                                                                                                                                                                                                              | Version: v3.7.0+ <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |
| `HEALTH_MONITOR_CHECK_INTERVAL`                         | Interval between health stats collection. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11888](https://github.com/blockscout/blockscout/pull/11888/)                                                                                                                                                                                                                                                     | Version: v8.0.0+ <br />Default: `1m` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                 |
| `HEALTH_MONITOR_BLOCKS_PERIOD`                          | New blocks indexed max delay in /health API endpoint. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11888](https://github.com/blockscout/blockscout/pull/11888/)                                                                                                                                                                                                                                         | Version: v8.0.0+ <br />Default: `5m` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                 |
| `HEALTH_MONITOR_BATCHES_PERIOD`                         | New batches indexed max delay in /health API endpoint. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11888](https://github.com/blockscout/blockscout/pull/11888/)                                                                                                                                                                                                                                        | Version: v8.0.0+ <br />Default: `4h` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                                 |
| `NEW_TAGS`                                              | Add public tag labels. More info in [#6316](https://github.com/blockscout/blockscout/pull/6316)                                                                                                                                                                                                                                                                                                                                                    | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `CUSTOM_CONTRACT_ADDRESSES_${tag_name}`                 | Specify addresses for some label. More info in [#6316](https://github.com/blockscout/blockscout/pull/6316)                                                                                                                                                                                                                                                                                                                                         | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                       |
| `SESSION_COOKIE_DOMAIN`                                 | Value of this env will be added to domain of session cookie. Implemented in [#6544](https://github.com/blockscout/blockscout/pull/6544)                                                                                                                                                                                                                                                                                                            | Needs Recompile: ☑️ <br />Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                             |
| `DECODE_NOT_A_CONTRACT_CALLS`                           | Allows decoding of contract calls directed to addresses which are not contracts. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                                                                                                                                                                                                        | Needs Recompile: ☑️ <br />Version: v5.1.0+ <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                             |
| `EIP_1559_ELASTICITY_MULTIPLIER`                        | EIP-1559 elasticity multiplier. See also `INDEXER_OPTIMISM_L2_HOLOCENE_TIMESTAMP`. Implemented in [#7253](https://github.com/blockscout/blockscout/pull/7253)                                                                                                                                                                                                                                                                                      | Version: v5.1.3+ <br />Default: `2` <br />Applications: API                                                                                                                                                                                                                                                                                                                           |
| `EIP_1559_BASE_FEE_MAX_CHANGE_DENOMINATOR`              | EIP-1559 base fee max change denominator. See also `INDEXER_OPTIMISM_L2_HOLOCENE_TIMESTAMP`. Implemented in [#9202](https://github.com/blockscout/blockscout/pull/9202)                                                                                                                                                                                                                                                                            | Version: v6.2.0+ <br />Default: `8` <br />Applications: API                                                                                                                                                                                                                                                                                                                           |
| `EIP_1559_BASE_FEE_LOWER_BOUND_WEI`                     | Minimum boundary for base fee calculation in `wei`. Implemented in [#12370](https://github.com/blockscout/blockscout/pull/12370).                                                                                                                                                                                                                                                                                                                  | Version: v8.1.0+ <br />Default: `0` <br />Applications: API                                                                                                                                                                                                                                                                                                                           |
| `BLOCK_MINER_GETS_BURNT_FEES`                           | If `true`, the Burnt fees are added to block miner profit and displayed in UI as zero. Implemented in [#13894](https://github.com/blockscout/blockscout/pull/13894).                                                                                                                                                                                                                                                                               | Version: v10.0.0+ <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                                                      |
| `ADDRESSES_TABS_COUNTERS_TTL`                           | TTL for cached tabs counters (works only for counters which are \< 51, if counter >= 51, then ttl == :infinity). Implemented in [#8512](https://github.com/blockscout/blockscout/pull/8512)                                                                                                                                                                                                                                                        | Version: v5.3.0+ <br />Default: `10m` <br />Applications: API                                                                                                                                                                                                                                                                                                                         |
| `API_INTERNAL_TRANSACTIONS_INDEXING_FINISHED_THRESHOLD` | In the case when the 1st tx in the chain already has internal transactions, If the number of blocks in `pending_block_operations` is less than the value in this env var, Blockscout will consider that indexing of internal transactions is finished, otherwise, it will consider that indexing is still taking place and the indexing banner will appear at the top. Implemented in [#7576](https://github.com/blockscout/blockscout/pull/7576). | Version: v5.2.0+ <br />Default: `1000` <br />Applications: API                                                                                                                                                                                                                                                                                                                        |
| `SHRINK_INTERNAL_TRANSACTIONS_ENABLED`                  | Variable to enable internal transactions shrinking logic. Implemented in [#10567](https://github.com/blockscout/blockscout/pull/10567).                                                                                                                                                                                                                                                                                                            | Version: v6.8.0+ <br />Default: `false` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |
| `HACKNEY_DEFAULT_POOL_SIZE`                             | Size of `default` hackney pool. Implemented in [#12406](https://github.com/blockscout/blockscout/pull/12406).                                                                                                                                                                                                                                                                                                                                      | Version: v8.1.0+ <br />Default: `1000` <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                               |
| `UNIVERSAL_PROXY_CONFIG_URL`                            | Config URL for universal proxy. Implemented in [#12442](https://github.com/blockscout/blockscout/pull/12442).                                                                                                                                                                                                                                                                                                                                      | Version: v8.1.0+ <br />Default: `https://raw.githubusercontent.com/blockscout/backend-configs/refs/heads/main/universal-proxy-config.json` <br />Applications: API                                                                                                                                                                                                                    |
| `UNIVERSAL_PROXY_CONFIG`                                | JSON-encoded configuration string used to define settings for the universal proxy. Implemented in [#13787](https://github.com/blockscout/blockscout/pull/13787).                                                                                                                                                                                                                                                                                   | Version: v10.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                      |
| `K8S_SERVICE`                                           | Kubernetes service name for Elixir nodes clusterization, more info on how to configure it can be found here [https://hexdocs.pm/libcluster/Cluster.Strategy.Kubernetes.DNS.html](https://hexdocs.pm/libcluster/Cluster.Strategy.Kubernetes.DNS.html). Implemented in [#13080](https://github.com/blockscout/blockscout/pull/13080).                                                                                                                | Version: v9.2.0+ <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                                                                                                                                                                                              |

## Database Management

| Variable                          | Description                                                                                                                                                                                                                                          | Parameters                                                                             |
| --------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- |
| `DATABASE_URL`                    | Defines the Postgres Database endpoint.                                                                                                                                                                                                              | Required: ✅ <br />Version: All <br />Default: (empty) <br />Applications: API, Indexer |
| `TEST_DATABASE_URL`               | Defines the endpoint of the Postgres Database that is used during testing. Implemented in [#9662](https://github.com/blockscout/blockscout/pull/9662).                                                                                               | Version: v6.6.0+ <br />Default: (empty) <br />Applications: API, Indexer               |
| `DATABASE_READ_ONLY_API_URL`      | Defines the Postgres Database read-only replica endpoint. If provided, most of the read queries from API v2 and UI go through this endpoint.                                                                                                         | Version: All <br />Default: (empty) <br />Applications: API                            |
| `TEST_DATABASE_READ_ONLY_API_URL` | Defines the endpoint of the Postgres Database read-only replica used during testing. If provided, most read queries from API v2 and UI go through this endpoint. Implemented in [#9662](https://github.com/blockscout/blockscout/pull/9662).         | Version: v6.6.0+ <br />Default: (empty) <br />Applications: API                        |
| `DATABASE_EVENT_URL`              | Variable to define the Postgres Database endpoint that will be used by event listener process. Applicable for separate indexer and API setup. More info in related PR. Implemented in [#10164](https://github.com/blockscout/blockscout/pull/10164). | Version: v6.8.0+ <br />Default: (empty) <br />Applications: API                        |
| `DATABASE_EVENT_POOL_SIZE`        | Variable to define the pool size for DB repo `DATABASE_EVENT_URL`. Applicable for separate indexer and API setup. Implemented in [#13064](https://github.com/blockscout/blockscout/pull/13064).                                                      | Version: v9.1.0+ <br />Default: 10<br />Applications: API, Indexer                     |
| `REPLICA_MAX_LAG`                 | Defines the max lag for read-only replica. If the actual lag is higher than this, replica is considered unavailable and all requests to it are redirected to main DB. Implemented in [#11020](https://github.com/blockscout/blockscout/pull/11020)   | Version: v6.10.0+ <br />Default: 5m <br />Applications: API                            |
| `DATABASE_QUEUE_TARGET`           | Management of [DB queue target](https://hexdocs.pm/db_connection/DBConnection.html#start_link/2-queue-config). Implemented in [#8991](https://github.com/blockscout/blockscout/pull/8991).                                                           | Version: v5.4.0+ <br />Default: `50ms` <br />Applications: API, Indexer                |
| `POOL_SIZE`                       | Defines the number of database connections allowed excluding read-only API endpoints requests.                                                                                                                                                       | Version: All <br />Default: `50` <br />Applications: API, Indexer                      |
| `POOL_SIZE_API`                   | Defines the number of database connections allowed for read-only API endpoints requests.                                                                                                                                                             | Version: v4.1.0+ <br />Default: `50` <br />Applications: API                           |
| `ECTO_USE_SSL`                    | Production environment variable to use SSL on Ecto queries.                                                                                                                                                                                          | Version: All <br />Default: `TRUE` <br />Applications: API, Indexer                    |

## JSON RPC Node Management

| Variable                                  | Description                                                                                                                                                                                                                                | Parameters                                                                                      |
| ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------- |
| `ETHEREUM_JSONRPC_VARIANT`                | Tells the application which RPC Client the node is using (i.e. `erigon`, `geth`, `nethermind`, `besu`, `filecoin`, or `anvil`) (See Client Settings for more info)                                                                         | Required: ✅ <br />Version: All <br />Default: `geth` <br />Applications: API, Indexer           |
| `ETHEREUM_JSONRPC_HTTP_URL`               | The RPC endpoint used to fetch blocks, transactions, receipts, tokens.                                                                                                                                                                     | Required: ✅ <br />Version: All <br />Default: `localhost:8545` <br />Applications: API, Indexer |
| `ETHEREUM_JSONRPC_FALLBACK_HTTP_URL`      | Fallback JSON RPC HTTP url. Implemented in [#7246](https://github.com/blockscout/blockscout/pull/7246)                                                                                                                                     | Version: v5.1.4+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_HTTP_URLS`              | Analogue of `ETHEREUM_JSONRPC_HTTP_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                                  | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_FALLBACK_HTTP_URLS`     | Analogue of `ETHEREUM_JSONRPC_FALLBACK_HTTP_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                         | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_TRACE_URL`              | The RPC endpoint specifically for the Erigon/Geth/Nethermind/Besu client used by `trace_block` and `trace_replayTransaction`. This can be used to designate a tracing node.                                                                | Version: All <br />Default: `localhost:8545` <br />Applications: API, Indexer                   |
| `ETHEREUM_JSONRPC_FALLBACK_TRACE_URL`     | Fallback JSON RPC trace url. Implemented in [#7246](https://github.com/blockscout/blockscout/pull/7246)                                                                                                                                    | Version: v5.1.4+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_TRACE_URLS`             | Analogue of `ETHEREUM_JSONRPC_TRACE_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                                 | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_FALLBACK_TRACE_URLS`    | Analogue of `ETHEREUM_JSONRPC_FALLBACK_TRACE_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                        | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_ETH_CALL_URL`           | JSON RPC url for `eth_call` method. Implemented in [#9112](https://github.com/blockscout/blockscout/pull/9112)                                                                                                                             | Version: v6.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_FALLBACK_ETH_CALL_URL`  | Fallback JSON RPC `eth_call` url. Implemented in [#9511](https://github.com/blockscout/blockscout/pull/9511)                                                                                                                               | Version: v6.3.0+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_ETH_CALL_URLS`          | Analogue of `ETHEREUM_JSONRPC_ETH_CALL_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                              | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_FALLBACK_ETH_CALL_URLS` | Analogue of `ETHEREUM_JSONRPC_FALLBACK_ETH_CALL_URL` for multiple values. Implemented in [#10934](https://github.com/blockscout/blockscout/pull/10934)                                                                                     | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer                       |
| `ETHEREUM_JSONRPC_WS_URL`                 | The WebSockets RPC endpoint used to subscribe to the `newHeads` subscription alerting the indexer to fetch new blocks.                                                                                                                     | Version: All <br />Default: `ws://localhost:8546` <br />Applications: Indexer                   |
| `ETHEREUM_JSONRPC_FALLBACK_WS_URL`        | The fallback WebSockets RPC endpoint used to subscribe to the `newHeads` subscription alerting the indexer to fetch new blocks. Implemented in [#10407](https://github.com/blockscout/blockscout/pull/10407).                              | Version: v6.8.0+ <br />Default: (empty) <br />Applications: Indexer                             |
| `ETHEREUM_JSONRPC_WS_RETRY_INTERVAL`      | The interval between retries of connecting to WebSocket RPC endpoint after the previous attempt is failed. Implemented in [#10407](https://github.com/blockscout/blockscout/pull/10407).                                                   | Version: v6.8.0+ <br />Default: 1m <br />Applications: Indexer                                  |
| `ETHEREUM_JSONRPC_TRANSPORT`              | Specifies the transport for Blockscout to connect to the Ethereum Node. Available transports are `http` and `ipc`. If `ipc` is selected, also set `IPC_PATH` variable.                                                                     | Version: v3.1.0+ <br />Default: `http` <br />Applications: API, Indexer                         |
| `ETHEREUM_JSONRPC_HTTP_INSECURE`          | If `true` is set, allows insecure HTTP connections to the archive node. For instance, it allows to bypass expired SSL certificate at the archive node endpoint. Implemented in [#6573](https://github.com/blockscout/blockscout/pull/6573) | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_HTTP_TIMEOUT`           | Timeout for ethereum json rpc http requests in seconds. Implemented in [#7089](https://github.com/blockscout/blockscout/pull/7089)                                                                                                         | Version: v5.1.2+ <br />Default: `60` <br />Applications: API, Indexer                           |
| `ETHEREUM_JSONRPC_USER`                   | User in basic auth for JSON RPC endpoint. Implemented in [#6897](https://github.com/blockscout/blockscout/pull/6897)                                                                                                                       | Version: v5.1.2+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_PASSWORD`               | Password in basic auth for JSON RPC endpoint. Implemented in [#6897](https://github.com/blockscout/blockscout/pull/6897)                                                                                                                   | Version: v5.1.2+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_HTTP_HEADERS`           | Custom headers for JSON RPC endpoint in form of json object, example: `{"x-api-key": "nbvkhadvnbkdfav", "x-id": "ndjkfvndfkjv"}`. Implemented in [#7898](https://github.com/blockscout/blockscout/pull/7898)                               | Version: v5.2.1+ <br />Default: (empty) <br />Applications: API, Indexer                        |
| `ETHEREUM_JSONRPC_WAIT_PER_TIMEOUT`       | Wait time for each recent timeout from node. Implemented in [#8292](https://github.com/blockscout/blockscout/pull/8292)                                                                                                                    | Version: v5.2.3+ <br />Default: `20s` <br />Applications: API, Indexer                          |
| `ETHEREUM_JSONRPC_HTTP_GZIP_ENABLED`      | If `true`, then send gzip encoding header and expect encoding in response. Implemented in [#11292](https://github.com/blockscout/blockscout/pull/11292).                                                                                   | Version: v6.10.0+ <br />Default: `false` <br />Applications: API, Indexer                       |
| `IPC_PATH`                                | Path to the IPC file of the running node if IPC transport is chosen.                                                                                                                                                                       | Version: v2.1.1+ <br />Default: (empty) <br />Applications: API, Indexer                        |

## Indexer Management

| Variable                                                      | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Parameters                                                                                               |
| ------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------- |
| `BLOCK_TRANSFORMER`                                           | Transformer for blocks: base or clique.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | Version: v1.3.4+ <br />Default: `base` <br />Applications: Indexer                                       |
| `DISABLE_INDEXER`                                             | If `true`, indexer application doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Version: v2.0.3+ <br />Default: `false` <br />Applications: API, Indexer                                 |
| `DISABLE_REALTIME_INDEXER`                                    | If `true`, realtime fetcher doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v4.1.6+ <br />Default: `false` <br />Applications: Indexer                                      |
| `FIRST_BLOCK`                                                 | The block number, where import of blocks by catchup fetcher begins from.                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v1.3.8+ <br />Default: `0` <br />Applications: API, Indexer                                     |
| `LAST_BLOCK`                                                  | The block number, where import of blocks by catchup fetcher stops.                                                                                                                                                                                                                                                                                                                                                                                                                                                               | Version: v2.0.3+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `TRACE_FIRST_BLOCK`                                           | The block number, where indexing of internal transactions begins from.                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Version: v4.1.0+ <br />Default: `0` <br />Applications: API, Indexer                                     |
| `TRACE_LAST_BLOCK`                                            | The block number, where indexing of internal transactions stops.                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | Version: v4.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `BLOCK_RANGES`                                                | Block ranges to import by catchup fetcher. Example: `BLOCK_RANGES="1..3,123..500,30..50,500..latest"`. Implemented in [#5783](https://github.com/blockscout/blockscout/pull/5783)                                                                                                                                                                                                                                                                                                                                                | Version: v4.1.7+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `FETCH_REWARDS_WAY`                                           | Tells the application how to calculate block rewards, by fetching via json\_rpc (`trace_block`) or manual by block params (`manual`).                                                                                                                                                                                                                                                                                                                                                                                            | Version: v4.1.4+ <br />Default: `trace_block` <br />Applications: Indexer                                |
| `IPFS_GATEWAY_URL`                                            | IPFS gateway url for fetching token instance metadata from IPFS including token instance icon.                                                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v5.3.0+ <br />Default: `https://ipfs.io/ipfs` <br />Applications: Indexer                       |
| `IPFS_GATEWAY_URL_PARAM_KEY`                                  | The key of the parameter to add to IPFS gateway url. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                                                                 | Version: v6.5.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `IPFS_GATEWAY_URL_PARAM_VALUE`                                | The value of the parameter to add to IPFS gateway url. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                                                               | Version: v6.5.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `IPFS_GATEWAY_URL_PARAM_LOCATION`                             | Whether to add extra params: to query string or to the headers. Available values: query/header. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                      | Version: v6.5.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `IPFS_PUBLIC_GATEWAY_URL`                                     | IPFS public gateway url which is used by frontend to display IPFS resources such as token instance image.                                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v6.8.0+ <br />Default: `https://ipfs.io/ipfs` <br />Applications: API                           |
| `ETHEREUM_JSONRPC_DEBUG_TRACE_TRANSACTION_TIMEOUT`            | Timeout for `debug_traceTransaction`/`debug_traceBlockByNumber` JSON RPC method requests in case of `geth` archive node. Supported time formats: [https://pkg.go.dev/time#ParseDuration](https://pkg.go.dev/time#ParseDuration). Introduced in [#5505](https://github.com/blockscout/blockscout/pull/5505)                                                                                                                                                                                                                       | Version: v4.1.3+ <br />Default: `5s` <br />Applications: Indexer                                         |
| `ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES`                   | If `true`, all the requests with the method `eth_getBalance` with any block as parameter but `latest` are ignored. Implemented in [#6001](https://github.com/blockscout/blockscout/pull/6001)                                                                                                                                                                                                                                                                                                                                    | Version: v5.0.0+ <br />Default: `false` <br />Applications: API, Indexer                                 |
| `ETHEREUM_JSONRPC_PENDING_TRANSACTIONS_TYPE`                  | Defines which method will be used for fetching pending transactions: `default` - default method for fetching internal transactions for current `ETHEREUM_JSONRPC_VARIANT`, `geth` - `txpool_content` method will be used, `parity` - `parity_pendingTransactions` will be used. Implemented in [#6001](https://github.com/blockscout/blockscout/pull/6155)                                                                                                                                                                       | Version: v5.0.0+ <br />Default: `default` <br />Applications: Indexer                                    |
| `MIN_MISSING_BLOCK_NUMBER_BATCH_SIZE`                         | Batch size for min missing block number updater. Implemented in [#6583](https://github.com/blockscout/blockscout/pull/6583).                                                                                                                                                                                                                                                                                                                                                                                                     | Version: v5.0.0+ <br />Default: `100000` <br />Applications: API, Indexer                                |
| `WITHDRAWALS_FIRST_BLOCK`                                     | The block number, where import of withdrawals by catchup fetcher begins from. Should be the block where withdrawals upgrade occurred on the chain. Implemented in [#6694](https://github.com/blockscout/blockscout/pull/6694).                                                                                                                                                                                                                                                                                                   | Version: v5.1.5+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `ETHEREUM_JSONRPC_ARCHIVE_BALANCES_WINDOW`                    | Max block number gap from latest for which balances requests can be processed when `ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES` env var is set to `true`. Implemented in [#8673](https://github.com/blockscout/blockscout/pull/8673)                                                                                                                                                                                                                                                                                              | Version: v5.3.1+ <br />Default: `200` <br />Applications: API, Indexer                                   |
| `DISABLE_CATCHUP_INDEXER`                                     | If `true`, catchup fetcher doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | Version: v5.3.2+ <br />Default: `false` <br />Applications: Indexer                                      |
| `TRACE_BLOCK_RANGES`                                          | Block ranges for traceable blocks. Example: `TRACE_BLOCK_RANGES="1..3,123..500,30..50,500..latest"`. Implemented in [#8960](https://github.com/blockscout/blockscout/pull/8960)                                                                                                                                                                                                                                                                                                                                                  | Version: v5.4.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `ETHEREUM_JSONRPC_GETH_TRACE_BY_BLOCK`                        | Enable tracing by block for geth variant. Implemented in [#9072](https://github.com/blockscout/blockscout/pull/9072)                                                                                                                                                                                                                                                                                                                                                                                                             | Version: v6.1.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `MISSING_BALANCE_OF_TOKENS_WINDOW_SIZE`                       | Minimal blocks count until the next token balance request will be executed for tokens that doesn't implement `balanceOf` function. Implemented in [#10142](https://github.com/blockscout/blockscout/pull/10142)                                                                                                                                                                                                                                                                                                                  | Version: v6.8.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `ETHEREUM_JSONRPC_GETH_ALLOW_EMPTY_TRACES`                    | Allow transactions to not have internal transactions. Implemented in [#10200](https://github.com/blockscout/blockscout/pull/10200)                                                                                                                                                                                                                                                                                                                                                                                               | Version: v6.8.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_ADDRESS_COIN_BALANCE_FETCHER`                | If `true`, coin balances fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v4.1.3+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_BLOCK_REWARD_FETCHER`                        | if `true`, block rewards fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v4.1.3+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_CATALOGED_TOKEN_UPDATER_FETCHER`             | If `true`, cataloged tokens metadata fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v4.1.3+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_EMPTY_BLOCKS_SANITIZER`                      | Empty blocks sanitizer is disabled if `true`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | Version: v5.1.2+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_HOT_SMART_CONTRACTS_FETCHER`                 | If `true`, `Indexer.Fetcher.Stats.HotSmartContracts` won't be started. Implemented in [#13471](https://github.com/blockscout/blockscout/pull/13471).                                                                                                                                                                                                                                                                                                                                                                             | Version: v9.3.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_INTERNAL_TRANSACTIONS_FETCHER`               | If `true`, internal transactions fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | Version: v4.1.2+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_PENDING_TRANSACTIONS_FETCHER`                | If `true`, pending transactions fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | Version: v4.1.2+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_REPLACED_TRANSACTION_FETCHER`                | If `true`, `Indexer.Fetcher.ReplacedTransaction` fetcher doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                            | Version: v6.8.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_ERC_1155_SANITIZE_FETCHER`    | If `true`, `erc-1155-sanitize` token instance fetcher doesn't run. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                   | Version: v6.2.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_ERC_721_SANITIZE_FETCHER`     | If `true`, `erc-721-sanitize` token instance fetcher doesn't run. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                    | Version: v6.2.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_REALTIME_FETCHER`             | If `true`, `realtime` token instance fetcher doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v5.1.4+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_REFETCH_FETCHER`              | If `true`, the Token instance fetcher, which re-fetches NFT collections marked to refetch, doesn't run. Implemented in [#10263](https://github.com/blockscout/blockscout/pull/10263).                                                                                                                                                                                                                                                                                                                                            | Version: v7.0.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_RETRY_FETCHER`                | If `true`, `retry` token instance fetcher doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Version: v5.1.4+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_SANITIZE_FETCHER`             | If `true`, `sanitize` token instance fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v5.1.4+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_DISABLE_WITHDRAWALS_FETCHER`                         | If `true`, withdrawals fetcher is disabled. Implemented in [#6694](https://github.com/blockscout/blockscout/pull/6694).                                                                                                                                                                                                                                                                                                                                                                                                          | Version: v5.1.5+ <br />Default: `true` <br />Applications: Indexer                                       |
| `INDEXER_BLOCK_REWARD_BATCH_SIZE`                             | Batch size for block reward fetcher. Implemented in [#6952](https://github.com/blockscout/blockscout/pull/6952).                                                                                                                                                                                                                                                                                                                                                                                                                 | Version: v5.1.2+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_BLOCK_REWARD_CONCURRENCY`                            | Concurrency for block reward fetcher. Implemented in [#6952](https://github.com/blockscout/blockscout/pull/6952).                                                                                                                                                                                                                                                                                                                                                                                                                | Version: v5.1.2+ <br />Default: `4` <br />Applications: Indexer                                          |
| `INDEXER_CATCHUP_BLOCKS_BATCH_SIZE`                           | Batch size for blocks catchup fetcher. Implemented in [#6196](https://github.com/blockscout/blockscout/pull/6196).                                                                                                                                                                                                                                                                                                                                                                                                               | Version: v5.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_CATCHUP_BLOCKS_CONCURRENCY`                          | Concurrency for blocks catchup fetcher. Implemented in [#6196](https://github.com/blockscout/blockscout/pull/6196).                                                                                                                                                                                                                                                                                                                                                                                                              | Version: v5.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_CATCHUP_BLOCK_INTERVAL`                              | Interval between blocks catchup fetcher tasks. Implemented in [#7489](https://github.com/blockscout/blockscout/pull/7489).                                                                                                                                                                                                                                                                                                                                                                                                       | Version: v5.1.5+ <br />Default: `0s` <br />Applications: Indexer                                         |
| `INDEXER_CATCHUP_MISSING_RANGES_BATCH_SIZE`                   | Batch size for missing ranges collector. Implemented in [#6583](https://github.com/blockscout/blockscout/pull/6583).                                                                                                                                                                                                                                                                                                                                                                                                             | Version: v5.0.0+ <br />Default: `100000` <br />Applications: Indexer                                     |
| `INDEXER_COIN_BALANCES_BATCH_SIZE`                            | Batch size for coin balances fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                                | Version: v5.0.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_COIN_BALANCES_CONCURRENCY`                           | Concurrency for coin balances fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                               | Version: v5.0.0+ <br />Default: `4` <br />Applications: Indexer                                          |
| `INDEXER_COIN_BALANCES_FETCHER_INIT_QUERY_LIMIT`              | Limit for coin balance fetcher init queries. Implemented in [#7996](https://github.com/blockscout/blockscout/pull/7996).                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v5.3.0+ <br />Default: `2000` <br />Applications: Indexer                                       |
| `INDEXER_DB_EVENT_NOTIFICATIONS_CLEANUP_ENABLED`              | If `true`, `Indexer.Utils.EventNotificationsCleaner` process starts. Implemented in [#12738](https://github.com/blockscout/blockscout/pull/12738)                                                                                                                                                                                                                                                                                                                                                                                | Version: v9.0.0+ <br />Default: `true`<br />Applications: Indexer                                        |
| `INDEXER_DB_EVENT_NOTIFICATIONS_CLEANUP_INTERVAL`             | Interval between DB event notifications cleanup. [Time format](backend-env-variables.md#time-format). Implemented in [#12738](https://github.com/blockscout/blockscout/pull/12738)                                                                                                                                                                                                                                                                                                                                               | Version: v9.0.0+ <br />Default: `2m` <br />Applications: Indexer                                         |
| `INDEXER_DB_EVENT_NOTIFICATIONS_CLEANUP_MAX_AGE`              | Max age of DB event notifications before they are cleaned up. [Time format](backend-env-variables.md#time-format). Implemented in [#12738](https://github.com/blockscout/blockscout/pull/12738)                                                                                                                                                                                                                                                                                                                                  | Version: v9.0.0+ <br />Default: `5m` <br />Applications: Indexer                                         |
| `INDEXER_EMPTY_BLOCKS_SANITIZER_BATCH_SIZE`                   | Batch size for empty block sanitizer (re-fetcher). Default value changed from 100 to 10 in the release `v6.10.1` ([#11555](https://github.com/blockscout/blockscout/pull/11555))                                                                                                                                                                                                                                                                                                                                                 | Version: v4.1.3+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_EMPTY_BLOCKS_SANITIZER_INTERVAL`                     | Interval for empty block sanitizer. Implemented in [#8658](https://github.com/blockscout/blockscout/pull/8658)                                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v5.3.0+ <br />Default: `5m` <br />Applications: Indexer                                         |
| `INDEXER_EMPTY_BLOCKS_SANITIZER_HEAD_OFFSET`                  | Minimal age for block to be processed by empty block sanitizer. Implemented in [#13132](https://github.com/blockscout/blockscout/pull/13132)                                                                                                                                                                                                                                                                                                                                                                                     | Version: v9.2.0+ <br />Default: `1000` <br />Applications: Indexer                                       |
| `INDEXER_FETCHER_INIT_QUERY_LIMIT`                            | Limit for all fetchers init queries. Implemented in [#7697](https://github.com/blockscout/blockscout/pull/7697).                                                                                                                                                                                                                                                                                                                                                                                                                 | Version: v5.2.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_GRACEFUL_SHUTDOWN_PERIOD`                            | Time that will be given to the block fetchers when stopping the application before they are killed. Implemented in [#9729](https://github.com/blockscout/blockscout/pull/9729)                                                                                                                                                                                                                                                                                                                                                   | Version: v6.5.0+ <br />Default: `5m` <br />Applications: Indexer                                         |
| `INDEXER_HIDE_INDEXING_PROGRESS_ALERT`                        | If `true`, indexer progress alert will be disabled even if initial catchup indexing is still in place. Implemented in [#7360](https://github.com/blockscout/blockscout/pull/7360).                                                                                                                                                                                                                                                                                                                                               | Version: v5.1.5+ <br />Default: `false` <br />Applications: API                                          |
| `INDEXER_INTERNAL_TRANSACTIONS_BATCH_SIZE`                    | Batch size for internal transactions fetcher. Implemented in [#6450](https://github.com/blockscout/blockscout/pull/6450).                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v5.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_INTERNAL_TRANSACTIONS_CONCURRENCY`                   | Concurrency for internal transactions fetcher. Implemented in [#6450](https://github.com/blockscout/blockscout/pull/6450).                                                                                                                                                                                                                                                                                                                                                                                                       | Version: v5.0.0+ <br />Default: `4` <br />Applications: Indexer                                          |
| `INDEXER_INTERNAL_TRANSACTIONS_FETCH_ORDER`                   | Order of fetching internal transactions from node. Possible values: `asc`, `desc`. Implemented in [#10912](https://github.com/blockscout/blockscout/pull/10912)                                                                                                                                                                                                                                                                                                                                                                  | Version: v6.9.0+ <br />Default: `asc` <br />Applications: Indexer                                        |
| `INDEXER_INTERNAL_TRANSACTIONS_TRACER_TYPE`                   | Tracer type for `debug_traceTransaction`/`debug_traceBlockByNumber` requests for geth-like nodes. Possible values are: `js` to use custom Blockscout js tracer, `call_tracer` to use built-in `callTracer` geth tracer, `opcode` to use built-in `Struct/opcode logger` geth tracer, `polygon_edge` to work with Polygon edge nodes. Implemented in [#6721](https://github.com/blockscout/blockscout/pull/6721), [#7513](https://github.com/blockscout/blockscout/pull/7513)                                                     | Version: v5.1.0+ <br />Default: `call_tracer` <br />Applications: Indexer                                |
| `INDEXER_INTERNAL_TRANSACTIONS_DELETE_QUEUE_BATCH_SIZE`       | Batch size for internal transactions delete queue handler. Implemented in [#13121](https://github.com/blockscout/blockscout/pull/13121).                                                                                                                                                                                                                                                                                                                                                                                         | Version: v9.2.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_INTERNAL_TRANSACTIONS_DELETE_QUEUE_CONCURRENCY`      | Concurrency for internal transactions delete queue handler. Implemented in [#13121](https://github.com/blockscout/blockscout/pull/13121).                                                                                                                                                                                                                                                                                                                                                                                        | Version: v9.2.0+ <br />Default: `1` <br />Applications: Indexer                                          |
| `INDEXER_INTERNAL_TRANSACTIONS_DELETE_QUEUE_THRESHOLD`        | Threshold for internal transactions delete queue handler. Implemented in [#13121](https://github.com/blockscout/blockscout/pull/13121).                                                                                                                                                                                                                                                                                                                                                                                          | Version: v9.2.0+ <br />Default: `0s` <br />Applications: Indexer                                         |
| `INDEXER_MEMORY_LIMIT`                                        | Memory soft limit for the indexer.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               | Version: v4.1.3+ <br />Default: `1Gb` <br />Applications: Indexer                                        |
| `INDEXER_PENDING_TRANSACTIONS_SANITIZER_INTERVAL`             | Interval between pending transactions sanitizing. Implemented in [#11601](https://github.com/blockscout/blockscout/pull/11601).                                                                                                                                                                                                                                                                                                                                                                                                  | Version: v6.10.1 <br />Default: `1h` <br />Applications: Indexer                                         |
| `INDEXER_REALTIME_FETCHER_MAX_GAP`                            | Max gap between consecutive `latest` blocks that will be filled by realtime fetcher. Implemented in [#7393](https://github.com/blockscout/blockscout/pull/7393)                                                                                                                                                                                                                                                                                                                                                                  | Version: v5.1.5+ <br />Default: `1000` <br />Applications: Indexer                                       |
| `INDEXER_REALTIME_FETCHER_POLLING_PERIOD`                     | Period between polling the `latest` block in realtime fetcher. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11783](https://github.com/blockscout/blockscout/pull/11783)                                                                                                                                                                                                                                                                                                               | Version: v7.0.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_RECEIPTS_BATCH_SIZE`                                 | Batch size for transaction receipts fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v5.0.0+ <br />Default: `250` <br />Applications: Indexer                                        |
| `INDEXER_RECEIPTS_CONCURRENCY`                                | Concurrency for transaction receipts fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v5.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_SIGNED_AUTHORIZATION_STATUS_BATCH_SIZE`              | Batch size (number of blocks) for EIP7702 authorizations status fetcher. Implemented in [#12451](https://github.com/blockscout/blockscout/pull/12451).                                                                                                                                                                                                                                                                                                                                                                           | Version: v9.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_SYSTEM_MEMORY_PERCENTAGE`                            | Percentage of total memory available to the VM that an application can use if `INDEXER_MEMORY_LIMIT` is not set. Implemented in [#10697](https://github.com/blockscout/blockscout/pull/10697).                                                                                                                                                                                                                                                                                                                                   | Version: v6.9.0+ <br />Default: `60` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_BALANCES_BATCH_SIZE`                           | Batch size for token balances fetcher. Implemented in [#7439](https://github.com/blockscout/blockscout/pull/7439).                                                                                                                                                                                                                                                                                                                                                                                                               | Version: v5.1.5+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_TOKEN_BALANCES_CONCURRENCY`                          | Concurrency for token balances fetcher. Implemented in [#8167](https://github.com/blockscout/blockscout/pull/8167).                                                                                                                                                                                                                                                                                                                                                                                                              | Version: v5.2.2+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_BALANCES_EXPONENTIAL_TIMEOUT_COEFF`            | Coefficient to calculate exponential timeout. Implemented in [#10694](https://github.com/blockscout/blockscout/pull/10694).                                                                                                                                                                                                                                                                                                                                                                                                      | Version: v6.9.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_TOKEN_BALANCES_FETCHER_INIT_QUERY_LIMIT`             | Limit for token balance fetcher init queries. Implemented in [#8459](https://github.com/blockscout/blockscout/pull/8459).                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v5.2.3+ <br />Default: `100000` <br />Applications: Indexer                                     |
| `INDEXER_TOKEN_BALANCES_MAX_REFETCH_INTERVAL`                 | Maximum interval between attempts to fetch address token balance. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#10694](https://github.com/blockscout/blockscout/pull/10694).                                                                                                                                                                                                                                                                                                           | Version: v6.8.1+ <br />Default: `168h` <br />Applications: Indexer                                       |
| `INDEXER_TOKEN_CONCURRENCY`                                   | Concurrency for token fetcher. Implemented in [#8167](https://github.com/blockscout/blockscout/pull/8167).                                                                                                                                                                                                                                                                                                                                                                                                                       | Version: v5.2.2+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_ALLOWED_URI_PROTOCOLS`                | List of allowed URI protocols (schemes) for requests when fetching token instance metadata. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                                                                                                                                                                                                                                                        | Version: v8.0.0+ <br />Default: `http,https` <br />Applications: Indexer                                 |
| `INDEXER_TOKEN_INSTANCE_CIDR_BLACKLIST`                       | List of IP addresses in CIDR format to block when fetching token instance metadata. Example: `"0.0.0.0/32,192.168.0.0/16"`. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                                                                                                                                                                                                                        | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_TOKEN_INSTANCE_HOST_FILTERING_ENABLED`               | If `false`, the URL from which metadata is fetched will not be resolved to an IP address, and the IP address will not be checked against the blacklist. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                                                                                                                                                                                            | Version: v8.0.0+ <br />Default: `true` <br />Applications: Indexer                                       |
| `INDEXER_TOKEN_INSTANCE_REALTIME_BATCH_SIZE`                  | Batch size for `realtime` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313).                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v5.2.3+ <br />Default: `1` <br />Applications: Indexer                                          |
| `INDEXER_TOKEN_INSTANCE_REALTIME_CONCURRENCY`                 | Concurrency for `realtime` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v5.1.4+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_ENABLED`               | If `true`, `realtime` token instance fetcher will retry once on 404 and 500 error. Implemented in [#10036](https://github.com/blockscout/blockscout/pull/10036).                                                                                                                                                                                                                                                                                                                                                                 | Version: v6.6.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_TIMEOUT`               | Timeout for retry set by `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_ENABLED`. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#10036](https://github.com/blockscout/blockscout/pull/10036).                                                                                                                                                                                                                                                                                                   | Version: v6.6.0+ <br />Default: `5s` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_REFETCH_BATCH_SIZE`                   | Batch size for the Token instance fetcher, which re-fetches NFT collections marked to refetch. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313).                                                                                                                                                                                                                                                                                                                                                       | Version: v5.2.3+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_REFETCH_CONCURRENCY`                  | Concurrency for the Token instance fetcher, which re-fetches NFT collections marked to refetch. Implemented in [#10263](https://github.com/blockscout/blockscout/pull/10263).                                                                                                                                                                                                                                                                                                                                                    | Version: v5.1.4+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_RETRY_BATCH_SIZE`                     | Batch size for `retry` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313)                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v5.2.3+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_RETRY_CONCURRENCY`                    | Concurrency for `retry` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                      | Version: v5.1.4+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_RETRY_EXPONENTIAL_TIMEOUT_BASE`       | Base to calculate exponential timeout. Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                                                                                                                                             | Version: v6.8.0+ <br />Default: `2` <br />Applications: Indexer                                          |
| `INDEXER_TOKEN_INSTANCE_RETRY_EXPONENTIAL_TIMEOUT_COEFF`      | Coefficient to calculate exponential timeout. Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                                                                                                                                      | Version: v6.8.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_TOKEN_INSTANCE_RETRY_MAX_REFETCH_INTERVAL`           | Maximum interval between attempts to fetch token instance metadata. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                                         | Version: v6.8.0+ <br />Default: `168h` <br />Applications: Indexer                                       |
| `INDEXER_TOKEN_INSTANCE_SANITIZE_BATCH_SIZE`                  | Batch size for `sanitize` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313).                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v5.2.3+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_SANITIZE_CONCURRENCY`                 | Concurrency for `sanitize` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v5.1.4+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_TOKEN_INSTANCE_USE_BASE_URI_RETRY`                   | If `true`, and request to `tokenURI(tokenId)` failed with `VM execution error`, Blockscout will make request to `baseURI` and try to request metadata from baseURI + tokenId                                                                                                                                                                                                                                                                                                                                                     | Version: v6.2.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_AAVE_V3_POOL_CONTRACT`                    | Pool contract address for Aave v3 protocol. If not defined, Aave transaction actions are ignored by the indexer. Implemented in [#7185](https://github.com/blockscout/blockscout/pull/7185).                                                                                                                                                                                                                                                                                                                                     | Version: v5.1.3+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_ENABLE`                                   | If `true`, transaction action indexer is active. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                                                                     | Version: v5.1.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_MAX_TOKEN_CACHE_SIZE`                     | Maximum number of items in an internal cache of tx actions indexing process (to limit memory consumption). Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                           | Version: v5.1.0+ <br />Default: `100000` <br />Applications: Indexer                                     |
| `INDEXER_TX_ACTIONS_REINDEX_FIRST_BLOCK`                      | The first block of a block range for historical indexing or reindexing of tx actions. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                                | Version: v5.1.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_REINDEX_LAST_BLOCK`                       | The last block of a block range for historical indexing or reindexing of tx actions. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                                 | Version: v5.1.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_REINDEX_PROTOCOLS`                        | Comma-separated names of protocols which should be indexed or reindexed on historical blocks defined by the range. Example: `uniswap_v3,zkbob` - only these protocols will be indexed or reindexed for the defined block range. If the value is an empty string (or not defined), all supported protocols will be indexed/reindexed. This option is not applicable to `realtime` and `catchup` fetchers (it always indexes all supported protocols). Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582). | Version: v5.1.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_TX_ACTIONS_UNISWAP_V3_FACTORY_CONTRACT`              | UniswapV3Factory contract address. Implemented in [#7312](https://github.com/blockscout/blockscout/pull/7312).                                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v5.1.4+ <br />Default: `0x1F98431c8aD98523631AE4a59f267346ea31F984` <br />Applications: Indexer |
| `INDEXER_TX_ACTIONS_UNISWAP_V3_NFT_POSITION_MANAGER_CONTRACT` | NonfungiblePositionManager contract address for Uniswap v3. Implemented in [#7312](https://github.com/blockscout/blockscout/pull/7312).                                                                                                                                                                                                                                                                                                                                                                                          | Version: v5.1.4+ <br />Default: `0xC36442b4a4522E871399CD717aBDD847Ab11FE88` <br />Applications: Indexer |

## DB Migrations & Sanitizer Management

| Variable                                                                                             | Description                                                                                                                                                                                                                                                                                                                                                            | Parameters                                                               |
| ---------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| `MIGRATION_SHRINK_INTERNAL_TRANSACTIONS_BATCH_SIZE`                                                  | Batch size of the shrink internal transactions migration. *Note*: before release "v6.8.0", the default value was 1000. Implemented in [#10567](https://github.com/blockscout/blockscout/pull/10567), changed default value in [#10689](https://github.com/blockscout/blockscout/pull/10689). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798). | Version: v7.0.0+ <br />Default: 100 <br />Applications: API, Indexer     |
| `MIGRATION_SHRINK_INTERNAL_TRANSACTIONS_CONCURRENCY`                                                 | Concurrency of the shrink internal transactions migration. Implemented in [#10567](https://github.com/blockscout/blockscout/pull/10567). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                     | Version: v7.0.0+ <br />Default: 10 <br />Applications: API, Indexer      |
| `MIGRATION_TOKEN_INSTANCE_OWNER_CONCURRENCY`                                                         | Concurrency of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                             | Version: v7.0.0+ <br />Default: `5` <br />Applications: API, Indexer     |
| `MIGRATION_TOKEN_INSTANCE_OWNER_BATCH_SIZE`                                                          | Batch size of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                              | Version: v7.0.0+ <br />Default: `50` <br />Applications: API, Indexer    |
| `MIGRATION_TOKEN_INSTANCE_OWNER_ENABLED`                                                             | Enable of backfiller from [#8386](https://github.com/blockscout/blockscout/pull/8386) implemented in [#8752](https://github.com/blockscout/blockscout/pull/8752). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                            | Version: v7.0.0+ <br />Default: `false` <br />Applications: API, Indexer |
| `MIGRATION_TRANSACTIONS_TABLE_DENORMALIZATION_BATCH_SIZE`                                            | Number of transactions to denormalize (add block timestamp and consensus) in the batch. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                      | Version: v7.0.0+ <br />Default: `500` <br />Applications: API, Indexer   |
| `MIGRATION_TRANSACTIONS_TABLE_DENORMALIZATION_CONCURRENCY`                                           | Number of parallel denormalization transaction batches processing. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                                           | Version: v7.0.0+ <br />Default: `10` <br />Applications: API, Indexer    |
| `MIGRATION_TOKEN_TRANSFER_TOKEN_TYPE_BATCH_SIZE`                                                     | Number of token transfers to denormalize (add token\_type) in the batch. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                                     | Version: v7.0.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `MIGRATION_TOKEN_TRANSFER_TOKEN_TYPE_CONCURRENCY`                                                    | Number of parallel denormalization token transfer batches processing. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                                        | Version: v7.0.0+ <br />Default: `1` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_INCORRECT_NFT_BATCH_SIZE`                                                        | Number of token transfers to sanitize in the batch. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                                                          | Version: v7.0.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `MIGRATION_SANITIZE_INCORRECT_NFT_CONCURRENCY`                                                       | Number of parallel sanitizing token transfer batches processing. Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                                                                                             | Version: v7.0.0+ <br />Default: `1` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_INCORRECT_NFT_TIMEOUT`                                                           | Timeout between sanitizing token transfer batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                  | Version: v7.0.0+ <br />Default: `0` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_INCORRECT_WETH_BATCH_SIZE`                                                       | Number of token transfers to sanitize in the batch. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                            | Version: v7.0.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `MIGRATION_SANITIZE_INCORRECT_WETH_CONCURRENCY`                                                      | Number of parallel sanitizing token transfer batches processing. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                               | Version: v7.0.0+ <br />Default: `1` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_INCORRECT_WETH_TIMEOUT`                                                          | Timeout between sanitizing token transfer batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                  | Version: v7.0.0+ <br />Default: `0` <br />Applications: API, Indexer     |
| `MIGRATION_REINDEX_INTERNAL_TRANSACTIONS_STATUS_BATCH_SIZE`                                          | Number of internal transactions to reindex in the batch. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                       | Version: v7.0.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `MIGRATION_REINDEX_INTERNAL_TRANSACTIONS_STATUS_CONCURRENCY`                                         | Number of parallel reindexing internal transaction batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                         | Version: v7.0.0+ <br />Default: `1` <br />Applications: API, Indexer     |
| `MIGRATION_REINDEX_INTERNAL_TRANSACTIONS_STATUS_TIMEOUT`                                             | Timeout between reindexing internal transaction batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358). Renamed in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                            | Version: v7.0.0+ <br />Default: `0` <br />Applications: API, Indexer     |
| `MIGRATION_REINDEX_DUPLICATED_INTERNAL_TRANSACTIONS_BATCH_SIZE`                                      | Number of internal transactions to reindex in the batch. Implemented in [#12394](https://github.com/blockscout/blockscout/pull/12394).                                                                                                                                                                                                                                 | Version: v8.1.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_REINDEX_DUPLICATED_INTERNAL_TRANSACTIONS_CONCURRENCY`                                     | Number of parallel reindexing internal transaction batches processing. Implemented in [#12394](https://github.com/blockscout/blockscout/pull/12394).                                                                                                                                                                                                                   | Version: v8.1.0+ <br />Default: `1` <br />Applications: Indexer          |
| `MIGRATION_REINDEX_DUPLICATED_INTERNAL_TRANSACTIONS_TIMEOUT`                                         | Timeout between reindexing internal transaction batches processing. Implemented in [#12394](https://github.com/blockscout/blockscout/pull/12394).                                                                                                                                                                                                                      | Version: v8.1.0+ <br />Default: `0` <br />Applications: Indexer          |
| `MIGRATION_REINDEX_BLOCKS_WITH_MISSING_TRANSACTIONS_BATCH_SIZE`                                      | Number of blocks to reindex in the batch. Implemented in [#12559](https://github.com/blockscout/blockscout/pull/12559).                                                                                                                                                                                                                                                | Version: v9.0.0+ <br />Default: `10` <br />Applications: Indexer         |
| `MIGRATION_REINDEX_BLOCKS_WITH_MISSING_TRANSACTIONS_CONCURRENCY`                                     | Number of parallel reindexing block batches processing. Implemented in [#12559](https://github.com/blockscout/blockscout/pull/12559).                                                                                                                                                                                                                                  | Version: v9.0.0+ <br />Default: `1` <br />Applications: Indexer          |
| `MIGRATION_REINDEX_BLOCKS_WITH_MISSING_TRANSACTIONS_TIMEOUT`                                         | Timeout between reindexing block batches processing. Implemented in [#12559](https://github.com/blockscout/blockscout/pull/12559).                                                                                                                                                                                                                                     | Version: v9.0.0+ <br />Default: `0` <br />Applications: Indexer          |
| `MIGRATION_REINDEX_BLOCKS_WITH_MISSING_TRANSACTIONS_ENABLED`                                         | Enable reindex blocks with missing transactions migration. Implemented in [#12559](https://github.com/blockscout/blockscout/pull/12559).                                                                                                                                                                                                                               | Version: v9.0.0+ <br />Default: `false` <br />Applications: Indexer      |
| `MIGRATION_RESTORE_OMITTED_WETH_TOKEN_TRANSFERS_BATCH_SIZE`                                          | Number of logs to process in the batch. Implemented in [#10466](https://github.com/blockscout/blockscout/pull/10466)                                                                                                                                                                                                                                                   | Version: v6.8.0+ <br />Default: `50` <br />Applications: API, Indexer    |
| `MIGRATION_RESTORE_OMITTED_WETH_TOKEN_TRANSFERS_CONCURRENCY`                                         | Number of parallel logs batches processing. Implemented in [#10466](https://github.com/blockscout/blockscout/pull/10466)                                                                                                                                                                                                                                               | Version: v6.8.0+ <br />Default: `5` <br />Applications: API, Indexer     |
| `MIGRATION_RESTORE_OMITTED_WETH_TOKEN_TRANSFERS_TIMEOUT`                                             | Time interval between checks if queue is not empty. The same timeout multiplied by 2 used between checks if queue is not full. Implemented in [#10466](https://github.com/blockscout/blockscout/pull/10466)                                                                                                                                                            | Version: v6.8.0+ <br />Default: `250ms` <br />Applications: API, Indexer |
| `MIGRATION_SANITIZE_DUPLICATED_LOG_INDEX_LOGS_BATCH_SIZE`                                            | Number of logs to process in the batch. Implemented in [#11055](https://github.com/blockscout/blockscout/pull/11055)                                                                                                                                                                                                                                                   | Version: v6.9.0+ <br />Default: `500` <br />Applications: API, Indexer   |
| `MIGRATION_SANITIZE_DUPLICATED_LOG_INDEX_LOGS_CONCURRENCY`                                           | Number of parallel logs batches processing. Implemented in [#11055](https://github.com/blockscout/blockscout/pull/11055)                                                                                                                                                                                                                                               | Version: v6.9.0+ <br />Default: `10` <br />Applications: API, Indexer    |
| `MIGRATION_REFETCH_CONTRACT_CODES_BATCH_SIZE`                                                        | Number of addresses to process in the batch. Implemented in [#11055](https://github.com/blockscout/blockscout/pull/11055)                                                                                                                                                                                                                                              | Version: v6.9.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `MIGRATION_REFETCH_CONTRACT_CODES_CONCURRENCY`                                                       | Number of parallel addresses batches processing. Implemented in [#11055](https://github.com/blockscout/blockscout/pull/11055)                                                                                                                                                                                                                                          | Version: v6.9.0+ <br />Default: `5` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_VERIFIED_ADDRESSES_DISABLED`                                                     | Controls whether the migration that sanitizes verified addresses is disabled. If set to `true`, the migration will not run; if set to `false`, the migration will proceed. Implemented in [#11727](https://github.com/blockscout/blockscout/pull/11727).                                                                                                               | Version: v7.0.0+ <br />Default: `false` <br />Applications: API, Indexer |
| `MIGRATION_SANITIZE_VERIFIED_ADDRESSES_BATCH_SIZE`                                                   | Specifies the number of addresses to process in each batch during the sanitize verified addresses migration. Implemented in [#11727](https://github.com/blockscout/blockscout/pull/11727).                                                                                                                                                                             | Version: v7.0.0+ <br />Default: `500` <br />Applications: API, Indexer   |
| `MIGRATION_SANITIZE_VERIFIED_ADDRESSES_CONCURRENCY`                                                  | Determines how many concurrent processes will be used during the sanitize verified addresses migration. Implemented in [#11727](https://github.com/blockscout/blockscout/pull/11727).                                                                                                                                                                                  | Version: v7.0.0+ <br />Default: `1` <br />Applications: API, Indexer     |
| `MIGRATION_SANITIZE_VERIFIED_ADDRESSES_TIMEOUT`                                                      | Defines the timeout before processing each batch in the sanitize verified addresses migration. Follows the [time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11727](https://github.com/blockscout/blockscout/pull/11727).                                                                                                        | Version: v7.0.0+ <br />Default: `0s` <br />Applications: API, Indexer    |
| `MIGRATION_HEAVY_INDEX_OPERATIONS_CHECK_INTERVAL`                                                    | Interval between status checks of heavy db operation like index creation or dropping. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11604](https://github.com/blockscout/blockscout/pull/11604)                                                                                                                              | Version: v7.0.0+ <br />Default: `10m` <br />Applications: API, Indexer   |
| `MIGRATION_TOKEN_INSTANCE_ERC_1155_SANITIZE_CONCURRENCY`                                             | Concurrency for `erc-1155-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226). Default value and name changed in [#11543](https://github.com/blockscout/blockscout/pull/11543)                                                                                                                                | Version: v7.0.0+ <br />Default: `1` <br />Applications: Indexer          |
| `MIGRATION_TOKEN_INSTANCE_ERC_721_SANITIZE_CONCURRENCY`                                              | Concurrency for `erc-721-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226). Name changed in [#11543](https://github.com/blockscout/blockscout/pull/11543)                                                                                                                                                   | Version: v7.0.0+ <br />Default: `2` <br />Applications: Indexer          |
| `MIGRATION_TOKEN_INSTANCE_ERC_1155_SANITIZE_BATCH_SIZE`                                              | Batch size for `erc-1155-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226). Default value and name changed in [#11543](https://github.com/blockscout/blockscout/pull/11543)                                                                                                                                 | Version: v7.0.0+ <br />Default: `500` <br />Applications: Indexer        |
| `MIGRATION_TOKEN_INSTANCE_ERC_721_SANITIZE_BATCH_SIZE`                                               | Batch size for `erc-721-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226). Default value and name changed in [#11543](https://github.com/blockscout/blockscout/pull/11543)                                                                                                                                  | Version: v7.0.0+ <br />Default: `50` <br />Applications: Indexer         |
| `MIGRATION_TOKEN_INSTANCE_ERC_721_SANITIZE_TOKENS_BATCH_SIZE`                                        | Tokens batch size for `erc-721-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226). Name changed in [#11543](https://github.com/blockscout/blockscout/pull/11543)                                                                                                                                             | Version: v7.0.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_SMART_CONTRACT_LANGUAGE_DISABLED`                                                         | If set to `true`, the migration to the `language` field in the `smart_contracts` table will not start. If set to `false`, the migration proceeds as normal. Implemented in [#11813](https://github.com/blockscout/blockscout/pull/11813).                                                                                                                              | Version: v8.0.0+ <br />Default: `false` <br />Applications: Indexer      |
| `MIGRATION_SMART_CONTRACT_LANGUAGE_BATCH_SIZE`                                                       | Defines the number of records to be processed in each batch when migrating the `language` field in the `smart_contracts` table. Implemented in [#11813](https://github.com/blockscout/blockscout/pull/11813).                                                                                                                                                          | Version: v8.0.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_SMART_CONTRACT_LANGUAGE_CONCURRENCY`                                                      | Specifies how many concurrent processes can handle the `language` field migration. Implemented in [#11813](https://github.com/blockscout/blockscout/pull/11813).                                                                                                                                                                                                       | Version: v8.0.0+ <br />Default: `1` <br />Applications: Indexer          |
| `MIGRATION_BACKFILL_METADATA_URL_DISABLED`                                                           | If set to `true`, the backfiller of `metadata_url` field in the `token_instances` table will not start. If set to `false`, the migration proceeds as normal. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                             | Version: v8.0.0+ <br />Default: `false` <br />Applications: Indexer      |
| `MIGRATION_BACKFILL_METADATA_URL_BATCH_SIZE`                                                         | Defines the number of records to be processed in each batch when backfilling the `metadata_url` field in the `token_instances` table. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                                                    | Version: v8.0.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_BACKFILL_METADATA_URL_CONCURRENCY`                                                        | Specifies how many concurrent processes can handle the `metadata_url` field backfilling. Implemented in [#12102](https://github.com/blockscout/blockscout/pull/12102).                                                                                                                                                                                                 | Version: v8.0.0+ <br />Default: `5` <br />Applications: Indexer          |
| `MIGRATION_RECOVERY_WETH_TOKEN_TRANSFERS_CONCURRENCY`                                                | Specifies how many concurrent processes can handle the recovery WETH token transfers migration. Implemented in [#12065](https://github.com/blockscout/blockscout/pull/12065).                                                                                                                                                                                          | Version: v8.0.0+ <br />Default: `5` <br />Applications: Indexer          |
| `MIGRATION_RECOVERY_WETH_TOKEN_TRANSFERS_BATCH_SIZE`                                                 | Defines the number of records to be processed in each batch when recovery WETH token transfers. Implemented in [#12065](https://github.com/blockscout/blockscout/pull/12065).                                                                                                                                                                                          | Version: v8.0.0+ <br />Default: `50` <br />Applications: Indexer         |
| `MIGRATION_RECOVERY_WETH_TOKEN_TRANSFERS_TIMEOUT`                                                    | Defines the timeout between processing each batch (`batch_size` \* `concurrency`) in the recovery WETH token transfers migration. Follows the [time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#12065](https://github.com/blockscout/blockscout/pull/12065).                                                                     | Version: v8.0.0+ <br />Default: `0s` <br />Applications: Indexer         |
| `MIGRATION_RECOVERY_WETH_TOKEN_TRANSFERS_BLOCKS_BATCH_SIZE`                                          | Specifies the block range size selected for the recovery of WETH token transfer migration. Implemented in [#12065](https://github.com/blockscout/blockscout/pull/12065).                                                                                                                                                                                               | Version: v8.0.0+ <br />Default: `100000` <br />Applications: Indexer     |
| `MIGRATION_RECOVERY_WETH_TOKEN_TRANSFERS_HIGH_VERBOSITY`                                             | If set to `true`, enables high verbosity logging (logs each transaction hash, where missed transfers were restored) during the recovery of WETH token transfer migration. Implemented in [#12065](https://github.com/blockscout/blockscout/pull/12065).                                                                                                                | Version: v8.0.0+ <br />Default: `true` <br />Applications: Indexer       |
| `MIGRATION_MERGE_ADJACENT_MISSING_BLOCK_RANGES_BATCH_SIZE`                                           | Specifies the missing block range batch size selected for the merge migration. Implemented in [#12778](https://github.com/blockscout/blockscout/pull/12778).                                                                                                                                                                                                           | Version: v9.0.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_DELETE_ZERO_VALUE_INTERNAL_TRANSACTIONS_ENABLED`                                          | Enable of delete zero-value calls migration. Implemented in [#13305](https://github.com/blockscout/blockscout/pull/13305).                                                                                                                                                                                                                                             | Version: v9.3.0+ <br />Default: `false` <br />Applications: Indexer      |
| `MIGRATION_DELETE_ZERO_VALUE_INTERNAL_TRANSACTIONS_BATCH_SIZE`                                       | Specifies the block batch size selected for the delete zero-value calls migration. Implemented in [#13305](https://github.com/blockscout/blockscout/pull/13305).                                                                                                                                                                                                       | Version: v9.3.0+ <br />Default: `100` <br />Applications: Indexer        |
| `MIGRATION_DELETE_ZERO_VALUE_INTERNAL_TRANSACTIONS_STORAGE_PERIOD_DAYS`                              | Specifies the period for which recent zero-value calls won't be deleted in delete zero-value calls migration. Implemented in [#13305](https://github.com/blockscout/blockscout/pull/13305).                                                                                                                                                                            | Version: v9.3.0+ <br />Default: `30` <br />Applications: Indexer         |
| `MIGRATION_DELETE_ZERO_VALUE_INTERNAL_TRANSACTIONS_CHECK_INTERVAL`                                   | Specifies the interval between checking of new zero-value calls to be deleted in delete zero-value calls migration. Implemented in [#13305](https://github.com/blockscout/blockscout/pull/13305).                                                                                                                                                                      | Version: v9.3.0+ <br />Default: `1m` <br />Applications: Indexer         |
| `MIGRATION_FILL_INTERNAL_TRANSACTION_TO_ADDRESS_HASH_WITH_CREATED_CONTRACT_ADDRESS_HASH_BATCH_SIZE`  | Specifies the block batch size selected for the fill internal transaction `to_address_hash` migration. Implemented in [#13846](https://github.com/blockscout/blockscout/pull/13846).                                                                                                                                                                                   | Version: v10.0.0+ <br />Default: `100` <br />Applications: Indexer       |
| `MIGRATION_FILL_INTERNAL_TRANSACTION_TO_ADDRESS_HASH_WITH_CREATED_CONTRACT_ADDRESS_HASH_CONCURRENCY` | Specifies how many concurrent processes can handle the fill internal transaction `to_address_hash` migration. Implemented in [#13846](https://github.com/blockscout/blockscout/pull/13846).                                                                                                                                                                            | Version: v10.0.0+ <br />Default: `1` <br />Applications: Indexer         |
| `MIGRATION_FILL_INTERNAL_TRANSACTION_TO_ADDRESS_HASH_WITH_CREATED_CONTRACT_ADDRESS_HASH_TIMEOUT`     | Defines the timeout between processing each batch (`batch_size` \* `concurrency`) in the fill internal transaction `to_address_hash` migration. Implemented in [#13846](https://github.com/blockscout/blockscout/pull/13846).                                                                                                                                          | Version: v10.0.0+ <br />Default: `0s` <br />Applications: Indexer        |
| `MIGRATION_EMPTY_INTERNAL_TRANSACTIONS_DATA_BATCH_SIZE`                                              | Number of internal transactions to clear their data in the batch. Implemented in [#13893](https://github.com/blockscout/blockscout/pull/13893).                                                                                                                                                                                                                        | Version: v10.0.0+ <br />Default: `100` <br />Applications: Indexer       |
| `MIGRATION_EMPTY_INTERNAL_TRANSACTIONS_DATA_CONCURRENCY`                                             | Number of parallel clearing internal transaction data batches processing. Implemented in [#13893](https://github.com/blockscout/blockscout/pull/13893).                                                                                                                                                                                                                | Version: v10.0.0+ <br />Default: `1` <br />Applications: Indexer         |
| `MIGRATION_EMPTY_INTERNAL_TRANSACTIONS_DATA_TIMEOUT`                                                 | Timeout between clearing internal transaction data batches processing. Implemented in [#13893](https://github.com/blockscout/blockscout/pull/13893).                                                                                                                                                                                                                   | Version: v10.0.0+ <br />Default: `0` <br />Applications: Indexer         |

## Market

| Variable                                     | Description                                                                                                                                                                                                                                                                                                          | Parameters                                                                                              |
| -------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------- |
| `DISABLE_MARKET`                             | Disables all fetchers and any market data displaying. Setting this to `true` will disable all market-related functionality. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                            | Version: v8.0.0+ <br />Default: `false` <br />Applications: API, Indexer                                |
| `MARKET_NATIVE_COIN_SOURCE`                  | Source for realtime native coin price fetching. Possible values are: `coin_gecko`, `coin_market_cap`, `crypto_rank`, `mobula` and `dia`. Useful when multiple coin IDs are configured and you want to explicitly select the source. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).    | Version: v8.0.0+ <br />Default: `coin_gecko` <br />Applications: API                                    |
| `MARKET_SECONDARY_COIN_SOURCE`               | Source for realtime secondary coin fetching. Possible values are: `coin_gecko`, `coin_market_cap`, `crypto_rank`, `mobula` and `dia`. Useful when multiple secondary coin IDs are configured. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                          | Version: v8.0.0+ <br />Default: `coin_gecko` <br />Applications: API                                    |
| `MARKET_TOKENS_SOURCE`                       | Sets the source for tokens price fetching. Available values are `coin_gecko`, `crypto_rank`, `mobula`, `dia`. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                          | Version: v8.0.0+ <br />Default: `coin_gecko` <br />Applications: Indexer                                |
| `MARKET_NATIVE_COIN_HISTORY_SOURCE`          | Sets the source for price history fetching. Available values are `crypto_compare`, `coin_gecko`, `mobula`, `coin_market_cap`, `crypto_rank` and `dia`. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                 | Version: v8.0.0+ <br />Default: `crypto_compare` <br />Applications: Indexer                            |
| `MARKET_SECONDARY_COIN_HISTORY_SOURCE`       | Sets the source for secondary coin price history fetching. Available values are `crypto_compare`, `coin_gecko`, `mobula`, `coin_market_cap`, `crypto_rank` and `dia`. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                  | Version: v8.0.0+ <br />Default: `crypto_compare` <br />Applications: Indexer                            |
| `MARKET_MARKET_CAP_HISTORY_SOURCE`           | Sets the source for market cap history fetching. Available values are `coin_gecko` and `coin_market_cap`. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                              | Version: v8.0.0+ <br />Default: `coin_gecko` <br />Applications: Indexer                                |
| `MARKET_TVL_HISTORY_SOURCE`                  | Sets the source for TVL history fetching. Available value is `defillama`. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                              | Version: v8.0.0+ <br />Default: `defillama` <br />Applications: Indexer                                 |
| `MARKET_COINGECKO_PLATFORM_ID`               | [CoinGecko](https://www.coingecko.com/) platform id for which token prices are fetched, see full list in [`/asset_platforms`](https://api.coingecko.com/api/v3/asset_platforms) endpoint. Examples: "ethereum", "optimistic-ethereum". Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844). | Version: v8.0.0+ <br />Default: `ethereum` <br />Applications: Indexer                                  |
| `MARKET_COINGECKO_BASE_URL`                  | If set, overrides the Coingecko base URL. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: `https://api.coingecko.com/api/v3` <br />Applications: API, Indexer     |
| `MARKET_COINGECKO_BASE_PRO_URL`              | If set, overrides the Coingecko Pro base URL. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                          | Version: v8.0.0+ <br />Default: `https://pro-api.coingecko.com/api/v3` <br />Applications: API, Indexer |
| `MARKET_COINGECKO_API_KEY`                   | CoinGecko API key. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                     | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COINGECKO_COIN_ID`                   | Sets CoinGecko coin ID. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COINGECKO_SECONDARY_COIN_ID`         | Sets CoinGecko coin ID for secondary coin market chart. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COINMARKETCAP_BASE_URL`              | If set, overrides the CoinMarketCap base URL (Free and Pro). Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                           | Version: v8.0.0+ <br />Default: `https://pro-api.coinmarketcap.com/v2` <br />Applications: API, Indexer |
| `MARKET_COINMARKETCAP_API_KEY`               | CoinMarketCap API key. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                 | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COINMARKETCAP_COIN_ID`               | CoinMarketCap coin id. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                 | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COINMARKETCAP_SECONDARY_COIN_ID`     | CoinMarketCap coin id for secondary coin. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_CRYPTOCOMPARE_BASE_URL`              | If set, overrides the CryptoCompare base URL. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                          | Version: v8.0.0+ <br />Default: `https://min-api.cryptocompare.com` <br />Applications: API, Indexer    |
| `MARKET_CRYPTOCOMPARE_COIN_SYMBOL`           | CryptoCompare coin symbol for native coin (e.g., "OP" for Optimism). CryptoCompare uses symbols instead of IDs. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                        | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_CRYPTOCOMPARE_SECONDARY_COIN_SYMBOL` | CryptoCompare coin symbol for secondary coin market chart. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                             | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_CRYPTORANK_PLATFORM_ID`              | Sets Cryptorank platform ID. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                           | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_CRYPTORANK_BASE_URL`                 | If set, overrides the Cryptorank API url. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: `https://api.cryptorank.io/v1/` <br />Applications: API, Indexer        |
| `MARKET_CRYPTORANK_API_KEY`                  | Cryptorank API key. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                    | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_CRYPTORANK_COIN_ID`                  | Sets Cryptorank coin ID. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                               | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_CRYPTORANK_SECONDARY_COIN_ID`        | Sets Cryptorank coin ID for secondary coin. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                            | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_DEFILLAMA_COIN_ID`                   | DefiLlama coin id. Use the `name` field from the `/v2/chains` endpoint response (e.g., "OP Mainnet" for Optimism). Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                     | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_MOBULA_PLATFORM_ID`                  | Mobula platform ID. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                    | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_MOBULA_BASE_URL`                     | If set, overrides the Mobula API base URL. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                             | Version: v8.0.0+ <br />Default: `https://api.mobula.io/api/1` <br />Applications: API, Indexer          |
| `MARKET_MOBULA_API_KEY`                      | Mobula API key. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                        | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_MOBULA_COIN_ID`                      | Set Mobula coin ID. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                                    | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_MOBULA_SECONDARY_COIN_ID`            | Set Mobula coin ID for secondary coin. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                 | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                |
| `MARKET_COIN_FETCHER_ENABLED`                | If `false` disables fetching of realtime native coin price. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                            | Version: v8.0.0+ <br />Default: `true` <br />Applications: API                                          |
| `MARKET_COIN_CACHE_PERIOD`                   | Cache period for coin exchange rates. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                                  | Version: v8.0.0+ <br />Default: `10m` <br />Applications: API                                           |
| `MARKET_TOKENS_FETCHER_ENABLED`              | If `false` disables fetching of token prices. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                          | Version: v8.0.0+ <br />Default: `true` <br />Applications: Indexer                                      |
| `MARKET_TOKENS_INTERVAL`                     | Interval between batch requests of token prices. Can be decreased in order to fetch prices faster if you have pro rate limit. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                   | Version: v8.0.0+ <br />Default: `10s` <br />Applications: Indexer                                       |
| `MARKET_TOKENS_REFETCH_INTERVAL`             | Interval between refetching token prices, responsible for the relevance of prices. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                              | Version: v8.0.0+ <br />Default: `1h` <br />Applications: Indexer                                        |
| `MARKET_TOKENS_MAX_BATCH_SIZE`               | Batch size of a single token price request. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                            | Version: v8.0.0+ <br />Default: `500` <br />Applications: Indexer                                       |
| `MARKET_HISTORY_FETCHER_ENABLED`             | If `false` disables fetching of marked data history. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                   | Version: v8.0.0+ <br />Default: `true` <br />Applications: Indexer                                      |
| `MARKET_HISTORY_FETCH_INTERVAL`              | Interval to update data for the last day in the market history table. Introduced in [#9197](https://github.com/blockscout/blockscout/pull/9197).                                                                                                                                                                     | Version: v6.1.0+ <br />Default: `1h` <br />Applications: API, Indexer                                   |
| `MARKET_HISTORY_FIRST_FETCH_DAY_COUNT`       | Initial number of days to fetch for market history. Implemented in [#11844](https://github.com/blockscout/blockscout/pull/11844).                                                                                                                                                                                    | Version: v8.0.0+ <br />Default: `365` <br />Applications: Indexer                                       |
| `MARKET_DIA_BLOCKCHAIN`                      | Sets DIA platform from [https://www.diadata.org/docs/reference/apis/token-prices/api-endpoints/blockchains](https://www.diadata.org/docs/reference/apis/token-prices/api-endpoints/blockchains). Implemented in [#12678](https://github.com/blockscout/blockscout/pull/12678).                                       | Version: v9.3.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `MARKET_DIA_BASE_URL`                        | If set, overrides the DIA API url. Implemented in [#12678](https://github.com/blockscout/blockscout/pull/12678).                                                                                                                                                                                                     | Version: v9.3.0+ <br />Default: `https://api.diadata.org/v1` <br />Applications: API, Indexer           |
| `MARKET_DIA_COIN_ADDRESS_HASH`               | Sets address hash for native coin in DIA. Implemented in [#12678](https://github.com/blockscout/blockscout/pull/12678).                                                                                                                                                                                              | Version: v9.3.0+ <br />Default: (empty) <br />Applications: API                                         |
| `MARKET_DIA_SECONDARY_COIN_ADDRESS_HASH`     | Sets address hash for secondary coin in DIA. Implemented in [#12678](https://github.com/blockscout/blockscout/pull/12678).                                                                                                                                                                                           | Version: v9.3.0+ <br />Default: (empty) <br />Applications: API                                         |

## Cache Management

<Info>
  See the [Time format](/setup/env-variables/backend-env-variables#time-format) section for more information on variable formatting.
</Info>

| Variable                                              | Description                                                                                                                                                                                                                                                                                                                                                  | Parameters                                                               |
| ----------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------ |
| `CACHE_ADDRESS_COUNT_PERIOD`                          | Interval for restarting the task that calculates the total number of addresses.                                                                                                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: `30m` <br />Applications: API, Indexer   |
| `CACHE_ADDRESS_SUM_PERIOD`                            | Time to live of addresses sum (except burn address) cache. [Time format](/setup/env-variables/backend-env-variables#time-format). Starting from release v6.8.0+, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. Introduced in [#2862](https://github.com/poanetwork/blockscout/pull/2862). | Version: v4.1.3+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_ADDRESS_TRANSACTIONS_GAS_USAGE_COUNTER_PERIOD` | Interval to restart the task which calculates gas usage at the address.                                                                                                                                                                                                                                                                                      | Version: v4.1.3+ <br />Default: `30m` <br />Applications: API, Indexer   |
| `CACHE_ADDRESS_TRANSACTIONS_COUNTER_PERIOD`           | Time to live of address' transaction counter. [Time format](/setup/env-variables/backend-env-variables#time-format). Introduced in [#3330](https://github.com/poanetwork/blockscout/pull/3330).                                                                                                                                                              | Version: v3.4.0+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_ADDRESS_TOKENS_USD_SUM_PERIOD`                 | Managing of cache invalidation period for the sum of USD value of tokens per tokens' holder address.                                                                                                                                                                                                                                                         | Version: v3.5.0+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_ADDRESS_TOKEN_TRANSFERS_COUNTER_PERIOD`        | Interval to restart the task, which calculates the number of token transfers at the address. Implemented in [#4699](https://github.com/poanetwork/blockscout/pull/4699).                                                                                                                                                                                     | Version: v4.0.0+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_TOTAL_GAS_USAGE_PERIOD`                        | Interval to restart the task which calculates the total gas usage. Starting from release v6.8.0+, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers.                                                                                                                                           | Version: v4.1.3+ <br />Default: `2h` <br />Applications: API, Indexer    |
| `CACHE_TOKEN_HOLDERS_COUNTER_PERIOD`                  | Interval to restart the task which calculates holders count of the token.                                                                                                                                                                                                                                                                                    | Version: v4.1.3+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_TOKEN_TRANSFERS_COUNTER_PERIOD`                | Interval to restart the task which calculates transfers count of the token.                                                                                                                                                                                                                                                                                  | Version: v4.1.3+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `TOKEN_METADATA_UPDATE_INTERVAL`                      | Interval to restart the task which updates token metadata.                                                                                                                                                                                                                                                                                                   | Version: v2.0.1+ <br />Default: `48h` <br />Applications: API, Indexer   |
| `TOKEN_COUNTERS_UPDATE_INTERVAL`                      | Interval to restart the task which updates token counters (transfers count and holders count).                                                                                                                                                                                                                                                               | Version: v9.0.0+ <br />Default: `3h` <br />Applications: Indexer         |
| `CACHE_AVERAGE_BLOCK_PERIOD`                          | Time to initiate first calculation and caching of average block period after start/re-start of the application.                                                                                                                                                                                                                                              | Version: v4.1.3+ <br />Default: `30m` <br />Applications: API, Indexer   |
| `CACHE_AVERAGE_BLOCK_TIME_WINDOW`                     | The number of blocks to be taken into account in the calculations. Introduced in [#13470](https://github.com/blockscout/blockscout/pull/13470).                                                                                                                                                                                                              | Version: v9.2.0+ <br />Default: `100` <br />Applications: API, Indexer   |
| `CACHE_MARKET_HISTORY_PERIOD`                         | Update of market history cache.                                                                                                                                                                                                                                                                                                                              | Version: v4.1.3+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `TOKEN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD`           | A threshold to invalidate token balance cache.                                                                                                                                                                                                                                                                                                               | Version: v5.1.2+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `COIN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD`            | A threshold to invalidate coin balance cache.                                                                                                                                                                                                                                                                                                                | Version: v5.1.2+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CONTRACT_CODE_ON_DEMAND_FETCHER_THRESHOLD`           | An initial threshold (for exponential backoff) to fetch smart-contract bytecode on-demand. Implemented in [#9708](https://github.com/blockscout/blockscout/pull/9708).                                                                                                                                                                                       | Version: v6.4.0+ <br />Default: `5s` <br />Applications: API, Indexer    |
| `CACHE_BLOCK_COUNT_PERIOD`                            | Time to live of blocks with consensus count cache. Starting from release v6.8.0+, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. Introduced in [#1876](https://github.com/poanetwork/blockscout/pull/1876).                                                                                | Version: v4.1.3+ <br />Default: `2h` <br />Applications: API, Indexer    |
| `CACHE_TOTAL_GAS_USAGE_COUNTER_ENABLED`               | if `true`, enables cache for total gas usage counter.                                                                                                                                                                                                                                                                                                        | Version: v5.1.3+ <br />Default: `false` <br />Applications: API, Indexer |
| `CACHE_TXS_COUNT_PERIOD`                              | Time interval to restart the task that calculates the total txs count. Starting from release v6.8.0+, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers.                                                                                                                                       | Version: v4.1.3+ <br />Default: `2h` <br />Applications: API, Indexer    |
| `CACHE_TRANSACTIONS_24H_STATS_PERIOD`                 | Interval to update data for the last 24 hours transactions stats. Introduced in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                                                                                                 | Version: v6.3.0+ <br />Default: `1h` <br />Applications: API, Indexer    |
| `CACHE_FRESH_PENDING_TRANSACTIONS_COUNTER_PERIOD`     | Interval to update count of pending transactions that appeared less than half an hour ago. Introduced in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                                                                        | Version: v6.3.0+ <br />Default: `5m` <br />Applications: API, Indexer    |
| `CACHE_OPTIMISM_LAST_OUTPUT_ROOT_SIZE_COUNTER_PERIOD` | Interval to update data for the last output root size counter. Introduced in [#9532](https://github.com/blockscout/blockscout/pull/9532).                                                                                                                                                                                                                    | Version: v6.3.0+ <br />Default: `5m` <br />Applications: API, Indexer    |
| `CACHE_PENDING_OPERATIONS_COUNT_PERIOD`               | Time interval to restart the task which calculates the total pending operations count.  Introduced in [#12474](https://github.com/blockscout/blockscout/pull/12474).                                                                                                                                                                                         | Version: v10.0.0+ <br />Default: `5m` <br />Applications: API, Indexer   |

## Gas Price Oracle

| Variable                                    | Description                                                                                                                                                                                                                  | Parameters                                                               |
| ------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| `GAS_PRICE_ORACLE_NUM_OF_BLOCKS`            | Gas price oracle: number of blocks to calculate average gas price from                                                                                                                                                       | Version: v4.1.4+ <br />Default: `200` <br />Applications: API, Indexer   |
| `GAS_PRICE_ORACLE_SAFELOW_PERCENTILE`       | Gas price oracle: safelow percentile                                                                                                                                                                                         | Version: v4.1.4+ <br />Default: `35` <br />Applications: API, Indexer    |
| `GAS_PRICE_ORACLE_AVERAGE_PERCENTILE`       | Gas price oracle: average percentile                                                                                                                                                                                         | Version: v4.1.4+ <br />Default: `60` <br />Applications: API, Indexer    |
| `GAS_PRICE_ORACLE_FAST_PERCENTILE`          | Gas price oracle: fast percentile                                                                                                                                                                                            | Version: v4.1.4+ <br />Default: `90` <br />Applications: API, Indexer    |
| `GAS_PRICE_ORACLE_CACHE_PERIOD`             | Gas price oracle: period of gas prices update.                                                                                                                                                                               | Version: v4.1.4+ <br />Default: `30s` <br />Applications: API, Indexer   |
| `GAS_PRICE_ORACLE_SIMPLE_TRANSACTION_GAS`   | Gas price oracle: amount of gas for a simple coin transfer. Introduced in [#9044](https://github.com/blockscout/blockscout/pull/9044).                                                                                       | Version: v6.0.0+ <br />Default: `21000` <br />Applications: API, Indexer |
| `GAS_PRICE_ORACLE_SAFELOW_TIME_COEFFICIENT` | Average block time multiplied by this coefficient for safelow gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582). | Version: v6.3.0+ <br />Default: `5` <br />Applications: API, Indexer     |
| `GAS_PRICE_ORACLE_AVERAGE_TIME_COEFFICIENT` | Average block time multiplied by this coefficient for average gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582). | Version: v6.3.0+ <br />Default: `3` <br />Applications: API, Indexer     |
| `GAS_PRICE_ORACLE_FAST_TIME_COEFFICIENT`    | Average block time multiplied by this coefficient for fast gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582).    | Version: v6.3.0+ <br />Default: `1` <br />Applications: API, Indexer     |

## Main Page Dashboard

| Variable                            | Description                                                                                                                                                                                  | Parameters                                                      |   |                                                                 |
| ----------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- | - | --------------------------------------------------------------- |
| `GAS_PRICE`                         | Gas price in Gwei. If the variable is present, gas price displays on the main page.                                                                                                          | Version: v3.3.2+ <br />Default: (empty) <br />Applications: API |   |                                                                 |
| `TXS_STATS_ENABLED`                 | Disables or enables txs per day stats gathering.                                                                                                                                             | Version: v5.1.3+ <br />Default: `true` <br />Applications: API  |   |                                                                 |
| `SHOW_PRICE_CHART`                  | Disables or enables price and market cap of coin charts on the main page.                                                                                                                    | Version: v3.1.2+ <br />Default: `false` <br />Applications: API |   |                                                                 |
| `SHOW_PRICE_CHART_LEGEND`           | Showa price and market cap values under the chart even if price chart is not enabled via `SHOW_PRICE_CHART` env variable.                                                                    | Version: v5.1.4+ <br />Default: `false` <br />Applications: API |   |                                                                 |
| `SHOW_TXS_CHART`                    | Disables or enables txs count per day chart on the main page.                                                                                                                                | Version: v3.1.2+ <br />Default: `true` <br />Applications: API  |   |                                                                 |
| `TXS_HISTORIAN_INIT_LAG`            | The initial delay in txs count history fetching in order to display txs count per day history chart on the main page. [Time format](/setup/env-variables/backend-env-variables#time-format). | Version: v3.1.2+ <br />Default: `0` <br />Applications: API     |   |                                                                 |
| `TXS_STATS_DAYS_TO_COMPILE_AT_INIT` | Number of days for fetching of history of txs count per day in order to display it in txs count per day history chart on the main page.                                                      | Version: v3.1.2+ <br />Default: `40` <br />Applications: API    |   | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |

## Contract Management

| Variable                                               | Description                                                                                                                                                                                                                                      | Parameters                                                                                                                                                                                                |
| ------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `CONTRACT_VERIFICATION_ALLOWED_SOLIDITY_EVM_VERSIONS`  | Comma-separated list of allowed EVM versions for Solidity contract verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964), updated in [#7614](https://github.com/blockscout/blockscout/pull/7614). | Version: v5.2.0+ <br />Default: `homestead,tangerineWhistle,spuriousDragon,byzantium,constantinople,petersburg,istanbul,berlin,london,paris,shanghai,cancun,prague,osaka,default` <br />Applications: API |
| `CONTRACT_VERIFICATION_ALLOWED_VYPER_EVM_VERSIONS`     | Comma-separated list of allowed EVM versions for Vyper contract verification. This var was introduced in [#7614](https://github.com/blockscout/blockscout/pull/7614).                                                                            | Version: v5.2.0+ <br />Default: `byzantium,constantinople,petersburg,istanbul,berlin,paris,shanghai,cancun,osaka,default` <br />Applications: API                                                         |
| `CONTRACT_VERIFICATION_MAX_LIBRARIES`                  | Max amount of libraries to consider in smart-contract verification from flat/multi-part file(s). Implemented in [#6204](https://github.com/blockscout/blockscout/pull/6204).                                                                     | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                           |
| `CONTRACT_MAX_STRING_LENGTH_WITHOUT_TRIMMING`          | Hide long contract method data. For more details: [#4667](https://github.com/blockscout/blockscout/pull/4667)                                                                                                                                    | Version: v4.0.0+ <br />Default: `2040` <br />Applications: API                                                                                                                                            |
| `CONTRACT_DISABLE_INTERACTION`                         | If `true`, contract interactions via "Write contract" or "Write proxy contract" tabs are disabled. Introduced in [#7088](https://github.com/blockscout/blockscout/pull/7088)."                                                                   | Version: v5.1.2+ <br />Default: (empty) <br />Applications: API                                                                                                                                           |
| `CONTRACT_PROXY_IMPLEMENTATION_TTL_VIA_AVG_BLOCK_TIME` | If `false`, proxy contract implementation will be re-fetched immediately once someone opens proxy page bypassing average block time calculation. Implemented in [#9155](https://github.com/blockscout/blockscout/pull/9155).                     | Version: v6.1.0+ <br />Default: `true` <br />Applications: API                                                                                                                                            |
| `CONTRACT_AUDIT_REPORTS_AIRTABLE_URL`                  | URL of Airtable to store audit reports from users. Implemented in [#9120](https://github.com/blockscout/blockscout/pull/9120)                                                                                                                    | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                           |
| `CONTRACT_AUDIT_REPORTS_AIRTABLE_API_KEY`              | Access token for `CONTRACT_AUDIT_REPORTS_AIRTABLE_URL`. Implemented in [#9120](https://github.com/blockscout/blockscout/pull/9120)                                                                                                               | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                           |
| `CONTRACT_CERTIFIED_LIST`                              | Comma-separated list of smart-contract address hashes, to which "certified" flag should be applied. Implemented in [#9910](https://github.com/blockscout/blockscout/pull/9910)"                                                                  | Version: v6.5.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                           |
| `WHITELISTED_WETH_CONTRACTS`                           | Comma-separated list of smart-contract address hashes of WETH-like tokens which deposit and withdrawal events you'd like to index. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134)                                  | Version: v6.8.0+ <br />Default: (empty) <br />Applications: API, Indexer                                                                                                                                  |
| `WETH_TOKEN_TRANSFERS_FILTERING_ENABLED`               | Toggle for WETH token transfers filtering which was introduced in [#10134](https://github.com/blockscout/blockscout/pull/10134). Implemented in [#10208](https://github.com/blockscout/blockscout/pull/10208)                                    | Version: v6.1.0+ <br />Default: `false` <br />Applications: API, Indexer                                                                                                                                  |
| `CONTRACT_ENABLE_PARTIAL_REVERIFICATION`               | Toggle for enabling re-verification from partial to partial match. Implemented in [#11737](https://github.com/blockscout/blockscout/pull/11737)                                                                                                  | Version: v7.0.0+ <br />Default: `false` <br />Applications: API                                                                                                                                           |

## Bridged Tokens

| Variable                                  | Description                                                                                                                | Parameters                                                                                   |
| ----------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------- |
| `BRIDGED_TOKENS_ENABLED`                  | Variable to enable bridged tokens functionality. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169) | Needs Recompile: ☑️ Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer |
| `BRIDGED_TOKENS_ETH_OMNI_BRIDGE_MEDIATOR` | OMNI bridge mediator for ETH tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)             | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                     |
| `BRIDGED_TOKENS_BSC_OMNI_BRIDGE_MEDIATOR` | OMNI bridge mediator for BSC tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)             | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                     |
| `BRIDGED_TOKENS_POA_OMNI_BRIDGE_MEDIATOR` | OMNI bridge mediator for POA tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)             | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                     |
| `BRIDGED_TOKENS_AMB_BRIDGE_MEDIATORS`     | AMB bridge mediator. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)                             | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                     |
| `BRIDGED_TOKENS_FOREIGN_JSON_RPC`         | Ethereum mainnet JSON RPC. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)                       | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API, Indexer                     |

## Miscellaneous UI

| Variable                       | Description                                                                                                                                                                                                     | Parameters                                                      |
| ------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `HIDE_SCAM_ADDRESSES`          | Hides address of EOA/smart-contract/token from search results if the value is `true` and "scam" badge is assigned to that address. Implemented in [#10763](https://github.com/blockscout/blockscout/pull/10763) | Version: v6.9.0+ <br />Default: (empty) <br />Applications: API |
| `UNCLES_IN_AVERAGE_BLOCK_TIME` | Include or exclude non-consensus blocks in avg block time calculation. Exclude if `false`.                                                                                                                      | Version: v2.0.1+ <br />Default: `false` <br />Applications: API |
| `COIN_BALANCE_HISTORY_DAYS`    | Number of days to consider for coin balance history chart.                                                                                                                                                      | Version: v3.1.3+ <br />Default: `10` <br />Applications: API    |

## CSV Export

| Variable           | Description                                                                                                            | Parameters                                                      |
| ------------------ | ---------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `CSV_EXPORT_LIMIT` | Changes max number of rows in CSV export. Implemented in [#10497](https://github.com/blockscout/blockscout/pull/10497) | Version: v6.8.0+ <br />Default: `10000` <br />Applications: API |

## reCAPTCHA

<Info>
  Use Invisible reCAPTCHA v2 for the latest versions. If using a previous version only choose v2 or v3, do not use both (we recommend v2). reCAPTCHA v3 support may be discontinued in future updates. [More info on reCAPTCHA settings available here](/setup/configuration-options/recaptcha).
</Info>

| Variable                                                         | Description                                                                                                                                                                                                                                       | Parameters                                                       |
| ---------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------- |
| `RE_CAPTCHA_SECRET_KEY`                                          | Google reCAPTCHA v2 secret key. Used by advanced CSV export. Implemented in [#4747](https://github.com/blockscout/blockscout/pull/4747)                                                                                                           | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API  |
| `RE_CAPTCHA_CLIENT_KEY`                                          | Google reCAPTCHA v2 client key. Used by advanced CSV export in the embedded old UI. You don't need to set it for [the new UI](https://github.com/blockscout/frontend). Implemented in [#4747](https://github.com/blockscout/blockscout/pull/4747) | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API  |
| `RE_CAPTCHA_V3_SECRET_KEY`                                       | **Only compatible with frontend version v1.36.x. For later versions, use Invisible reCAPTCHA v2.** Google reCAPTCHA v3 secret key. Used by advanced CSV export. Implemented in [#7273](https://github.com/blockscout/blockscout/pull/7273)        | Version: v5.1.4+ <br />Default: (empty) <br />Applications: API  |
| `RE_CAPTCHA_V3_CLIENT_KEY`                                       | **Only compatible with frontend version v1.36.x. For later versions, use Invisible reCAPTCHA v2.** Google reCAPTCHA v3 client key. Used by advanced CSV export. Implemented in [#7273](https://github.com/blockscout/blockscout/pull/7273)        | Version: v5.1.4+ <br />Default: (empty) <br />Applications: API  |
| `RE_CAPTCHA_DISABLED`                                            | Disable reCAPTCHA. Implemented in [#7416](https://github.com/blockscout/blockscout/pull/7416)                                                                                                                                                     | Version: v5.1.5+ <br />Default: `false` <br />Applications: API  |
| `RE_CAPTCHA_CHECK_HOSTNAME`                                      | Disable reCAPTCHA hostname check. More details on [reCaptcha docs](https://developers.google.com/recaptcha/docs/domain_validation). Implemented in [#10706](https://github.com/blockscout/blockscout/pull/10706)                                  | Version: v6.9.0+ <br />Default: `true` <br />Applications: API   |
| `RE_CAPTCHA_SCORE_THRESHOLD`                                     | Changes reCAPTCHA score threshold. Implemented in [#11182](https://github.com/blockscout/blockscout/pull/11182)                                                                                                                                   | Version: v6.9.1+ <br />Default: `0.5` <br />Applications: API    |
| `RE_CAPTCHA_BYPASS_TOKEN`                                        | Bypass token that allows to skip reCAPTCHA check. Implemented in [#11682](https://github.com/blockscout/blockscout/pull/11682)                                                                                                                    | Version: v6.10.2+ <br />Default: (empty) <br />Applications: API |
| `RE_CAPTCHA_TOKEN_INSTANCE_REFETCH_METADATA_SCOPED_BYPASS_TOKEN` | API key that allows to skip reCAPTCHA check for requests to `/api/v2/tokens/{token_hash}/instances/{token_id}/refetch-metadata` endpoint. Implemented in [#12147](https://github.com/blockscout/blockscout/pull/12147)                            | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API  |

## API Rate Limits

| Variable                                          | Description                                                                                                                                                                                                                                                    | Parameters                                                                          |
| ------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| `API_RATE_LIMIT_BY_IP`                            | Global rate limit for an IP address for API v2 requests sent from UI. [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                              | Version: v5.1.3+ <br />Default: `300` <br />Applications: API                       |
| `API_RATE_LIMIT_BY_IP_TIME_INTERVAL`              | Time interval of rate limit set by `API_RATE_LIMIT_BY_IP`. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                          | Version: v5.1.3+ <br />Default: `1m` <br />Applications: API                        |
| `API_RATE_LIMIT_BY_WHITELISTED_IP`                | A dedicated API rate limit for whitelisted IPs. Implemented in [#5090](https://github.com/blockscout/blockscout/pull/5090)                                                                                                                                     | Version: v5.1.3+ <br />Default: `25 req/sec` <br />Applications: API                |
| `API_RATE_LIMIT_BY_WHITELISTED_IP_TIME_INTERVAL`  | Time interval for API rate limit by whitelisted IP. [Time format](\[backend-env-variables.md]\(http://backend-env-variables.md\)#time-format). Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386)                                    | Version: v9.0.0+ <br />Default: `1s` <br />Applications: API                        |
| `API_RATE_LIMIT_BY_KEY_TIME_INTERVAL`             | Time interval for API rate limit by key. [Time format](\[backend-env-variables.md]\(http://backend-env-variables.md\)#time-format). Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386)                                               | Version: v9.0.0+ <br />Default: `1s` <br />Applications: API                        |
| `API_RATE_LIMIT_BY_ACCOUNT_API_KEY_TIME_INTERVAL` | Time interval for API rate limit by account API key. [Time format](\[backend-env-variables.md]\(http://backend-env-variables.md\)#time-format). Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386)                                   | Version: v9.0.0+ <br />Default: `1s` <br />Applications: API                        |
| `API_RATE_LIMIT_BY_KEY`                           | A dedicated API rate limit per key for every type of API key (static or generated from Account module). Implemented in [#5080](https://github.com/blockscout/blockscout/pull/5080)                                                                             | Version: v4.1.1+ <br />Default: `10 req/sec` <br />Applications: API                |
| `API_RATE_LIMIT_UI_V2_WITH_TOKEN`                 | Rate limit after submitting correct CAPTCHA. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                                        | Version: v5.1.3+ <br />Default: `5` <br />Applications: API                         |
| `API_RATE_LIMIT_UI_V2_WITH_TOKEN_TIME_INTERVAL`   | Time interval for API rate limit for UI v2 with token. [Time format](\[backend-env-variables.md]\(http://backend-env-variables.md\)#time-format). Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386)                                 | Version: v9.0.0+ <br />Default: `1s` <br />Applications: API                        |
| `API_RATE_LIMIT_WHITELISTED_IPS`                  | Comma-separated whitelisted IPs list with dedicated rate limit. Implemented in [#5090](https://github.com/blockscout/blockscout/pull/5090)                                                                                                                     | Version: v4.1.1+ <br />Default: (empty) <br />Applications: API                     |
| `API_RATE_LIMIT_STATIC_API_KEY`                   | Static API key with dedicated API rate limit. Implemented in [#5080](https://github.com/blockscout/blockscout/pull/5080)                                                                                                                                       | Version: v4.1.1+ <br />Default: (empty) <br />Applications: API                     |
| `API_NO_RATE_LIMIT_API_KEY`                       | API key with no rate limit. Implemented in [#10515](https://github.com/blockscout/blockscout/pull/10515)                                                                                                                                                       | Version: v6.8.0+ <br />Default: (empty) <br />Applications: API                     |
| `API_RATE_LIMIT_DISABLED`                         | If `true`, any type of rate limit is ignored. Implemented in [#6908](https://github.com/blockscout/blockscout/pull/6908)                                                                                                                                       | Version: v5.1.0+ <br />Default: `false` <br />Applications: API                     |
| `API_RATE_LIMIT_IS_BLOCKSCOUT_BEHIND_PROXY`       | If `true`, then IP address of a client will be derived from proxy's headers (like `X-Forwarded-For`) using [RemoteIp](https://hexdocs.pm/remote_ip/RemoteIp.html) library. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)          | Version: v5.1.3+ <br />Default: `false` <br />Applications: API                     |
| `API_RATE_LIMIT_UI_V2_TOKEN_TTL`                  | TTL for token issued after submitting correct CAPTCHA for an API v2 requests from UI.  [Time format](\[backend-env-variables.md]\(http://backend-env-variables.md\)#time-format). Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386) | Version: v9.0.0+ <br />Default: `30m` <br />Applications: API                       |
| `API_RATE_LIMIT_CONFIG_URL`                       | URL to fetch API rate limit configuration from external source. Implemented in [#12386](https://github.com/blockscout/blockscout/pull/12386)                                                                                                                   | Version: v9.0.0+ <br />Default: (empty)<br />Applications: API                      |
| `API_RATE_LIMIT_HAMMER_REDIS_URL`                 | Redis DB URL for Hammer rate limit library. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                                         | Needs Recompile: ☑️ Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |
| `API_RATE_LIMIT_REMOTE_IP_HEADERS`                | Comma separated list of HTTP headers to extract the real client IP address when Blockscout is behind a proxy for rate limiting purposes. Implemented in [#12386](https://github.com/blockscout/blockscout/pull/13082)                                          | Version: v9.1.0+ <br />Default: `x-forwarded-for` <br />Applications: API           |
| `API_RATE_LIMIT_REMOTE_IP_KNOWN_PROXIES`          | Comma separated list of trusted proxy IP addresses or CIDR ranges that are allowed to set the client IP headers for rate limiting. Implemented in [#12386](https://github.com/blockscout/blockscout/pull/13082)                                                | Version: v9.1.0+ <br />Default: `(empty)` <br />Applications: API                   |
| `ETH_JSON_RPC_MAX_BATCH_SIZE`                     | Max batch size for Eth JSON RPC requests. Implemented in [#9409](https://github.com/blockscout/blockscout/pull/9409)                                                                                                                                           | Version: v6.3.0+ <br />Default: `5` <br />Applications: API                         |

## General application rate Limits

| Variable                                           | Description                                                                                                                                         | Parameters                                                      |
| -------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `RATE_LIMITER_REDIS_URL`                           | Redis DB URL for rate limiter. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218)                                         | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API |
| `RATE_LIMITER_ON_DEMAND_TIME_INTERVAL`             | Time interval of rate limit for on-demand fetchers. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218)                    | Version: v8.0.0+ <br />Default: `5s` <br />Applications: API    |
| `RATE_LIMITER_ON_DEMAND_LIMIT_BY_IP`               | Rate limit for an IP address for on-demand fetcher call. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218)               | Version: v8.0.0+ <br />Default: `100` <br />Applications: API   |
| `RATE_LIMITER_ON_DEMAND_EXPONENTIAL_TIMEOUT_COEFF` | Coefficient to calculate exponential timeout for on-demand rate limit. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218) | Version: v8.0.0+ <br />Default: `100` <br />Applications: API   |
| `RATE_LIMITER_ON_DEMAND_MAX_BAN_INTERVAL`          | Max time an IP address can be banned from on-demand fetcher calls. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218)     | Version: v8.0.0+ <br />Default: `1h` <br />Applications: API    |
| `RATE_LIMITER_ON_DEMAND_LIMITATION_PERIOD`         | Time after which the number of bans for the IP address will be reset. Implemented in [#12218](https://github.com/blockscout/blockscout/pull/12218)  | Version: v8.0.0+ <br />Default: `1h` <br />Applications: API    |

## GraphQL API

| Variable                                     | Description                                                                                                                                                                                                                                                                                                                        | Parameters                                                                                                                                             |
| -------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `API_GRAPHQL_ENABLED`                        | Enabling/disabling of GraphQL API. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751)                                                                                                                                                                                                                      | Version: v6.4.0+ <br />Default: `true` <br />Applications: API                                                                                         |
| `API_GRAPHQL_MAX_COMPLEXITY`                 | Limits the cost of GraphQL API queries. For more details, see the [`max_complexity`](https://hexdocs.pm/absinthe/complexity-analysis.html#complexity-analysis) documentation. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751), updated in [#11843](https://github.com/blockscout/blockscout/pull/11843) | Needs Recompile: ☑️ Version: v6.4.0+ <br />Default: `100` <br />Applications: API                                                                      |
| `API_GRAPHQL_TOKEN_LIMIT`                    | Query [token\_limit](https://hexdocs.pm/absinthe/complexity-analysis.html#token-limits) of Absinthe. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751)                                                                                                                                                    | Needs Recompile: ☑️ <br />Version: v6.4.0+ <br />Default: `1000` <br />Applications: API                                                               |
| `API_GRAPHQL_DEFAULT_TRANSACTION_HASH`       | Default transaction hash in a sample query to GraphiQL. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751).                                                                                                                                                                                                | Needs Recompile: ☑️ <br />Version: v6.4.0+ <br />Default: `0x69e3923eef50eada197c3336d546936d0c994211492c9f947a24c02827568f9f` <br />Applications: API |
| `API_GRAPHQL_RATE_LIMIT`                     | A global GraphQL API rate limit: number or requests per second for all users. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                                                           | Version: v6.4.0+ <br />Default: `10 req/sec` <br />Applications: API                                                                                   |
| `API_GRAPHQL_RATE_LIMIT_BY_KEY`              | A dedicated GraphQL API rate limit per static key. If this limit is less than stated in API plan, then `API_GRAPHQL_RATE_LIMIT_BY_KEY` used for key generated from Account module. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                      | Version: v6.4.0+ <br />Default: `10 req/sec` <br />Applications: API                                                                                   |
| `API_GRAPHQL_RATE_LIMIT_STATIC_API_KEY`      | Static GraphQL API key with dedicated GraphQL API rate limit. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                                                                           | Version: v6.4.0+ <br />Default: (empty) <br />Applications: API                                                                                        |
| `API_GRAPHQL_RATE_LIMIT_DISABLED`            | If `true`, any type of rate limit is ignored. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                                                                                           | Version: v6.4.0+ <br />Default: (empty) <br />Applications: API                                                                                        |
| `API_GRAPHQL_RATE_LIMIT_BY_IP`               | Global rate limit for an IP address for GraphQL API requests. [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                                                                                          | Version: v6.4.0+ <br />Default: `500` <br />Applications: API                                                                                          |
| `API_GRAPHQL_RATE_LIMIT_TIME_INTERVAL`       | Time interval of rate limit. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                                     | Version: v6.4.0+ <br />Default: `1s` <br />Applications: API                                                                                           |
| `API_GRAPHQL_RATE_LIMIT_BY_IP_TIME_INTERVAL` | Time interval of rate limit set by `API_GRAPHQL_RATE_LIMIT_BY_IP`. [Time format](/setup/env-variables/backend-env-variables#time-format). Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                               | Version: v6.4.0+ <br />Default: `1h` <br />Applications: API                                                                                           |

## Account Related

| Variable                                            | Description                                                                                                                                                                                                                 | Parameters                                                                                 |
| --------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------ |
| `ACCOUNT_ENABLED`                                   | Turn on/off account functionality. If value is`true`, account functionality is enabled.                                                                                                                                     | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_DATABASE_URL`                              | Account DB connection string                                                                                                                                                                                                | Version: v5.0.0+ <br />Default: value from `DATABASE_URL` <br />Applications: API          |
| `ACCOUNT_REDIS_URL`                                 | Account Redis connection string (for session storing configuration)                                                                                                                                                         | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_POOL_SIZE`                                 | Account DB `pool_size`                                                                                                                                                                                                      | Version: v5.0.0+ <br />Default: `50` <br />Applications: API                               |
| `ACCOUNT_AUTH0_DOMAIN`                              | Domain for [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                                | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_AUTH0_CLIENT_ID`                           | Auth0 client ID [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                           | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_AUTH0_CLIENT_SECRET`                       | Auth0 client secret [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                       | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_AUTH0_APPLICATION_ID`                      | Specifies the identifier for the application within Auth0. It's used to namespace user metadata in migrated Auth0 tenants. Implemented in [#12109](https://github.com/blockscout/blockscout/pull/12109).                    | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_SENDGRID_API_KEY`                          | Sendgrid API key for watchlist notifications functionality                                                                                                                                                                  | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_SENDGRID_SENDER`                           | Sendgrid sender email for watchlist notifications functionality                                                                                                                                                             | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_SENDGRID_TEMPLATE`                         | Sendgrid email template for watchlist notifications functionality                                                                                                                                                           | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_CLOAK_KEY`                                 | Account DB encryption key. [Instruction how to generate](https://hexdocs.pm/cloak_ecto/generate_keys.html#content)                                                                                                          | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                            |
| `ACCOUNT_VERIFICATION_EMAIL_RESEND_INTERVAL`        | Time before resending confirmation email. Implemented in [#7298](https://github.com/blockscout/blockscout/pull/7298).                                                                                                       | Version: v5.1.5+ <br />Default: `5m` <br />Applications: API                               |
| `ACCOUNT_PRIVATE_TAGS_LIMIT`                        | Limit for address & transaction tags. Implemented in [#8528](https://github.com/blockscout/blockscout/pull/8528).                                                                                                           | Version: v5.3.1+ <br />Default: `2000` <br />Applications: API                             |
| `ACCOUNT_WATCHLIST_ADDRESSES_LIMIT`                 | Limit for watch list addresses. Implemented in [#8528](https://github.com/blockscout/blockscout/pull/8528).                                                                                                                 | Version: v5.3.1+ <br />Default: `15` <br />Applications: API                               |
| `ACCOUNT_WATCHLIST_NOTIFICATIONS_LIMIT_FOR_30_DAYS` | Per account limit for watch list notifications sent for the last 30 days. Implemented in [#8966](https://github.com/blockscout/blockscout/pull/8966).                                                                       | Version: v5.3.3+ <br />Default: `1000` <br />Applications: API                             |
| `ACCOUNT_OTP_RESEND_INTERVAL`                       | Time before resending otp email. Implemented in [#10706](https://github.com/blockscout/blockscout/pull/10706).                                                                                                              | Version: v6.9.0+ <br />Default: `1m` <br />Applications: API                               |
| `ACCOUNT_SIWE_MESSAGE`                              | Message for Sign In With Ethereum authentication. Implemented in [#11178](https://github.com/blockscout/blockscout/pull/11178).                                                                                             | Version: v6.9.1+ <br />Default: `Sign in to Blockscout Account V2` <br />Applications: API |
| `ACCOUNT_DYNAMIC_ENV_ID`                            | Dynamic Environment ID, can be found here [https://app.dynamic.xyz/dashboard/developer/api](https://app.dynamic.xyz/dashboard/developer/api). Implemented in [#13786](https://github.com/blockscout/blockscout/pull/13786). | Version: v10.0.0+ <br />Default: (empty) <br />Applications: API                           |

## Specific Smart Contracts

| Variable                | Description                                                                                                                                                    | Parameters                                                                                                    |
| ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------- |
| `METADATA_CONTRACT`     | Used by POA Network to obtain Validators information to display in the UI.                                                                                     | Version: all <br />Default: (empty) <br />Applications: API, Indexer                                          |
| `VALIDATORS_CONTRACT`   | Used by POA Network to obtain the list of current validators.                                                                                                  | Version: all <br />Default: (empty) <br />Applications: API, Indexer                                          |
| `KEYS_MANAGER_CONTRACT` | Used by POA Network to set KeysManager proxy contract in order to obtain payout key by mining key. This needs to identify distributed reward to the validator. | Version: v3.1.2+ <br />Default: (empty) <br />Applications: API, Indexer                                      |
| `REWARDS_CONTRACT`      | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA`                                                              | Version: v2.0.4+ <br />Default: `0xeca443e8e1ab29971a45a9c57a6a9875701698a5` <br />Applications: API, Indexer |
| `TOKEN_BRIDGE_CONTRACT` | Token bridge proxy contract. For \`TokenBridge\` supply module.                                                                                                | Version: v1.3.2+ <br />Default: `0x7301CFA0e1756B71869E93d4e4Dca5c7d0eb0AA6` <br />Applications: API, Indexer |

## CDN

This feature was implemented in [#10675](https://github.com/blockscout/blockscout/pull/10675)

| Variable                                                  | Description                                                                                                              | Parameters                                                                                |
| --------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------- |
| `NFT_MEDIA_HANDLER_AWS_ACCESS_KEY_ID`                     | S3 API Access Key ID                                                                                                     | Version: v6.10.0+ <br />Default: (empty) <br />Applications: NFT\_MEDIA\_HANDLER          |
| `NFT_MEDIA_HANDLER_AWS_SECRET_ACCESS_KEY`                 | S3 API Secret Access Key                                                                                                 | Version: v6.10.0+ <br />Default: (empty) <br />Applications: NFT\_MEDIA\_HANDLER          |
| `NFT_MEDIA_HANDLER_AWS_BUCKET_HOST`                       | S3 API URL                                                                                                               | Version: v6.10.0+ <br />Default: (empty) <br />Applications: NFT\_MEDIA\_HANDLER          |
| `NFT_MEDIA_HANDLER_AWS_BUCKET_NAME`                       | S3 bucket name                                                                                                           | Version: v6.10.0+ <br />Default: (empty) <br />Applications: NFT\_MEDIA\_HANDLER          |
| `NFT_MEDIA_HANDLER_AWS_PUBLIC_BUCKET_URL`                 | Public S3 bucket URL                                                                                                     | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API                          |
| `NFT_MEDIA_HANDLER_ENABLED`                               | if `true`, CDN feature enabled                                                                                           | Version: v6.10.0+ <br />Default: `false` <br />Applications: Indexer, NFT\_MEDIA\_HANDLER |
| `NFT_MEDIA_HANDLER_REMOTE_DISPATCHER_NODE_MODE_ENABLED`   | if `true`, nft media handler is supposed to run separately.                                                              | Version: v6.10.0+ <br />Default: `false` <br />Applications: Indexer, NFT\_MEDIA\_HANDLER |
| `NFT_MEDIA_HANDLER_IS_WORKER`                             | if `true`, and `NFT_MEDIA_HANDLER_REMOTE_DISPATCHER_NODE_MODE_ENABLED=true` will be started only nft\_media\_handler app | Version: v6.10.0+ <br />Default: `false` <br />Applications: Indexer, NFT\_MEDIA\_HANDLER |
| `NFT_MEDIA_HANDLER_WORKER_CONCURRENCY`                    | Concurrency of media handling (resizing/uploading)                                                                       | Version: v6.10.0+ <br />Default: `10` <br />Applications: NFT\_MEDIA\_HANDLER             |
| `NFT_MEDIA_HANDLER_WORKER_BATCH_SIZE`                     | Number of url processed by one async task                                                                                | Version: v6.10.0+ <br />Default: `10` <br />Applications: NFT\_MEDIA\_HANDLER             |
| `NFT_MEDIA_HANDLER_WORKER_SPAWN_TASKS_TIMEOUT`            | Timeout before spawn new task                                                                                            | Version: v6.10.0+ <br />Default: `100ms` <br />Applications: NFT\_MEDIA\_HANDLER          |
| `NFT_MEDIA_HANDLER_BACKFILL_ENABLED`                      | If `true`, unprocessed token instances from DB are processed via nft\_media\_handler                                     | Version: v6.10.0+ <br />Default: `false` <br />Applications: Indexer                      |
| `NFT_MEDIA_HANDLER_BACKFILL_QUEUE_SIZE`                   | Max size of backfill queue                                                                                               | Version: v6.10.0+ <br />Default: `1000` <br />Applications: Indexer                       |
| `NFT_MEDIA_HANDLER_BACKFILL_ENQUEUE_BUSY_WAITING_TIMEOUT` | Timeout before new attempt to append item to backfill queue if it's full                                                 | Version: v6.10.0+ <br />Default: `1s` <br />Applications: Indexer                         |
| `NFT_MEDIA_HANDLER_CACHE_UNIQUENESS_MAX_SIZE`             | Max size of cache, where stored already uploaded token instances media                                                   | Version: v6.10.0+ <br />Default: `100_000` <br />Applications: Indexer                    |
| `NFT_MEDIA_HANDLER_BUCKET_FOLDER`                         | Folder in R2/S3 bucket, where media files are stored                                                                     | Version: v9.2.0+ <br />Default: (empty) <br />Applications: Indexer                       |

## Addresses Blacklist management

Section created as a result of [#11417](https://github.com/blockscout/blockscout/pull/11417)

| Variable                              | Description                                                                                                                                                   | Parameters                                                          |
| ------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| `ADDRESSES_BLACKLIST`                 | A comma-separated list of addresses to enable restricted access to them.                                                                                      | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API    |
| `ADDRESSES_BLACKLIST_KEY`             | A key to access blacklisted addresses (either by `ADDRESSES_BLACKLIST` or by blacklist provider). Can be passed via query param to the page's URL: `?key=...` | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API    |
| `ADDRESSES_BLACKLIST_PROVIDER`        | Blacklist provider type, available options: `blockaid`                                                                                                        | Version: v6.10.0+ <br />Default: `blockaid` <br />Applications: API |
| `ADDRESSES_BLACKLIST_URL`             | URL to fetch blacklist from                                                                                                                                   | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API    |
| `ADDRESSES_BLACKLIST_UPDATE_INTERVAL` | Interval between scheduled updates of blacklist                                                                                                               | Version: v6.10.0+ <br />Default: `15m` <br />Applications: API      |
| `ADDRESSES_BLACKLIST_RETRY_INTERVAL`  | Time to wait before new attempt of blacklist fetching, after abnormal termination of fetching task                                                            | Version: v6.10.0+ <br />Default: `5s` <br />Applications: API       |

## Prometheus Metrics Management

| Variable                                                            | Description                                                                                                                                                             | Parameters                                                        |
| ------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------- |
| `PUBLIC_METRICS_ENABLED`                                            | Enables the `/public-metrics` endpoint. Implemented in [#10469](https://github.com/blockscout/blockscout/pull/10469).                                                   | Version: v6.8.0+ <br />Default: `false` <br />Applications: API   |
| `PUBLIC_METRICS_UPDATE_PERIOD_HOURS`                                | Update frequency (in hours) for refreshing data at the `/public-metrics` endpoint. Implemented in [#10469](https://github.com/blockscout/blockscout/pull/10469).        | Version: v6.8.0+ <br />Default: 24 <br />Applications: API        |
| `INDEXER_METRICS_ENABLED`                                           | Flag to enable base indexer metrics. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539).                                                      | Version: v9.3.0+ <br />Default: true <br />Applications: Indexer  |
| `INDEXER_METRICS_ENABLED_TOKEN_INSTANCES_NOT_UPLOADED_TO_CDN_COUNT` | Flag to enable indexer metric: the count of token instances not uploaded to CDN. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539).          | Version: v9.3.0+ <br />Default: false <br />Applications: Indexer |
| `INDEXER_METRICS_ENABLED_FAILED_TOKEN_INSTANCES_METADATA_COUNT`     | Flag to enable indexer metric: the count of token instances with failed metadata fetches. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539). | Version: v9.3.0+ <br />Default: true <br />Applications: Indexer  |
| `INDEXER_METRICS_ENABLED_UNFETCHED_TOKEN_INSTANCES_COUNT`           | Flag to enable indexer metric: the count of token instances pending to fetch. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539).             | Version: v9.3.0+ <br />Default: true <br />Applications: Indexer  |
| `INDEXER_METRICS_ENABLED_MISSING_CURRENT_TOKEN_BALANCES_COUNT`      | Flag to enable indexer metric: the count of current token balances with missing values. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539).   | Version: v9.3.0+ <br />Default: true <br />Applications: Indexer  |
| `INDEXER_METRICS_ENABLED_MISSING_ARCHIVAL_TOKEN_BALANCES_COUNT`     | Flag to enable indexer metric: the count of archival token balances with missing values. Implemented in [#13539](https://github.com/blockscout/blockscout/pull/13539).  | Version: v9.3.0+ <br />Default: true <br />Applications: Indexer  |

## Old UI Management

| Variable                            | Description                                                                                                                                                       | Parameters                                                                          |
| ----------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| `NETWORK`                           | Environment variable for the main EVM network such as Ethereum or POA.                                                                                            | Version: All <br />Default: `POA` <br />Applications: API                           |
| `SUBNETWORK`                        | Environment variable for the subnetwork such as Core or Sokol Network. This will be displayed as selected in the chains list dropdown.                            | Version: All <br />Default: `POA Sokol` <br />Applications: API                     |
| `JSON_RPC`                          | JSON RPC endpoint of the chain for the WalletConnect integration. Implemented in [#4931](https://github.com/blockscout/blockscout/pull/4931)                      | Version: v4.1.0+ <br />Default: (empty) <br />Applications: API, Indexer            |
| `SHOW_MAINTENANCE_ALERT`            | Disables/enables announcement at the top of the explorer.                                                                                                         | Version: v3.6.0+ <br />Default: `false` <br />Applications: API                     |
| `MAINTENANCE_ALERT_MESSAGE`         | Message text of the announcement at the top of the explorer.                                                                                                      | Version: v3.6.0+ <br />Default: (empty) <br />Applications: API                     |
| `SHOW_ADDRESS_MARKETCAP_PERCENTAGE` | Configures market cap percentage column on the top accounts page.                                                                                                 | Version: v2.1.1+ <br />Default: `true` <br />Applications: API                      |
| `HIDE_BLOCK_MINER`                  | Hides miner/validator/sequencer on block page and tiles if the value is `true`. Implemented in [#4611](https://github.com/blockscout/blockscout/pull/4611)        | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API                     |
| `DISPLAY_TOKEN_ICONS`               | Displays token icons from Trust Wallet assets repository if `true`. Implemented in [#4596](https://github.com/blockscout/blockscout/pull/4596)                    | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API                     |
| `DISABLE_ADD_TO_MM_BUTTON`          | If `true`, "Add chain to MM" button doesn't appear. Implemented in [#6843](https://github.com/blockscout/blockscout/pull/6843)"                                   | Version: v5.1.0+ <br />Default: (empty) <br />Applications: API                     |
| `PERMANENT_DARK_MODE_ENABLED`       | If `true`, permanent dark mode is enabled. Dark mode switcher is hidden in this case. Implemented in [#6763](https://github.com/blockscout/blockscout/pull/6763)  | Version: v5.1.0+ <br />Default: (empty) <br />Applications: API                     |
| `PERMANENT_LIGHT_MODE_ENABLED`      | If `true`, permanent light mode is enabled. Dark mode switcher is hidden. Implemented in [#6838](https://github.com/blockscout/blockscout/pull/6838)              | Version: v5.1.0+ <br />Default: (empty) <br />Applications: API                     |
| `ADMIN_PANEL_ENABLED`               | if `true` admin/\* routes are available. Implemented in [#5208](https://github.com/blockscout/blockscout/pull/5208). **NOTE: Only Available for Hosted Clients.** | Needs Recompile: ☑️ Version: v4.1.2+ <br />Default: (empty) <br />Applications: API |

## Header and Footer

### Header

| Variable             | Description                                                                                                                                                                                                                                                                                                       | Parameters                                                                                                                                                                                                                                                                                                                                                                                                                      |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `LOGO`               | Environment variable for the header logo image location. The logo files names for different chains can be found [here](https://github.com/poanetwork/blockscout/tree/master/apps/block_scout_web/assets/static/images).                                                                                           | Version: all <br />Default: `/images/blockscout_logo.svg` <br />Applications: API                                                                                                                                                                                                                                                                                                                                               |
| `SHOW_TESTNET_LABEL` | Enables testnet label right after logo in the navigation panel. Implemented in [#5732](https://github.com/blockscout/blockscout/pull/5732)                                                                                                                                                                        | Version: v4.1.6+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                                                                 |
| `TESTNET_LABEL_TEXT` | The text inside the test label. Implemented in [#5732](https://github.com/blockscout/blockscout/pull/5732)                                                                                                                                                                                                        | Version: v4.1.6+ <br />Default: `Testnet` <br />Applications: API                                                                                                                                                                                                                                                                                                                                                               |
| `SUPPORTED_CHAINS`   | An array of supported chains displayed in the chains dropdown. This var was introduced in this PR [#1900](https://github.com/poanetwork/blockscout/pull/1900) and looks like an array of JSON objects.                                                                                                            | Version: v2.0.0+ <br />Default: `[ { title: "POA", url: "https://blockscout.com/poa/core" }, { title: "Sokol", url: "https://blockscout.com/poa/sokol", test_net?: true }, { title: "Gnosis Chain", url: "https://gnosis.blockscout.com/" }, { title: "Ethereum Classic", url: "https://etc.blockscout.com", other?: true }, { title: "RSK", url: "https://rootstock.blockscout.com", other?: true } ]` <br />Applications: API |
| `APPS_MENU`          | true/false. If true, the Apps navigation menu item appears.                                                                                                                                                                                                                                                       | Version: v3.3.1+ <br />Default: `false` <br />Applications: API                                                                                                                                                                                                                                                                                                                                                                 |
| `APPS`               | An array of embedded/external apps to display in Apps menu item. This var was introduced in this PR [#3184](https://github.com/poanetwork/blockscout/pull/3184) and looks like an array of JSON objects. An example of an embedded link is described here [#](https://github.com/blockscout/blockscout/pull/6397) | Version: v5.0.0+ <br />Default: (empty) <br />Applications: API                                                                                                                                                                                                                                                                                                                                                                 |

### Footer

| Variable                         | Description                                                                                                                                                                                                             | Parameters                                                                                                                               |
| -------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| `FOOTER_LOGO`                    | Environment variable for the footer logo image location. The logo files names for different chains can be found [here](https://github.com/poanetwork/blockscout/tree/master/apps/block_scout_web/assets/static/images). | Version: all <br />Default: `/images/blockscout_logo.svg` <br />Applications: API                                                        |
| `RELEASE_LINK`                   | The link to Blockscout release notes in the footer.                                                                                                                                                                     | Version: v1.3.5+ <br />Default: `https: //github.com/poanetwork/ blockscout/releases/ tag/${BLOCKSCOUT_VERSION}` <br />Applications: API |
| `BLOCKSCOUT_VERSION`             | Added to the footer to signify the current BlockScout version.                                                                                                                                                          | Version: v1.3.4+ <br />Default: (empty) <br />Applications: API                                                                          |
| `FOOTER_CHAT_LINK`               | Link to Chat menu item in the footer. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719).                                                                                                       | Version: v4.1.6+ <br />Default: `https://discord.gg/3CtNAqVMRV` <br />Applications: API                                                  |
| `FOOTER_FORUM_LINK_ENABLED`      | Enable forum menu item in the footer.                                                                                                                                                                                   | Version: v5.1.3+ <br />Default: `false` <br />Applications: API                                                                          |
| `FOOTER_FORUM_LINK`              | Link in Forum menu item in the footer. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719)                                                                                                       | Version: v4.1.6+ <br />Default: `https://forum.poa.network/c/blockscout` <br />Applications: API                                         |
| `FOOTER_TELEGRAM_LINK_ENABLED`   | Enable Telegram menu item in the footer. Implemented in [#7345](https://github.com/blockscout/blockscout/pull/7345).                                                                                                    | Version: v5.1.4+ <br />Default: `false` <br />Applications: API                                                                          |
| `FOOTER_TELEGRAM_LINK`           | Link in Telegram menu item in the footer. Implemented in [#7345](https://github.com/blockscout/blockscout/pull/7345).                                                                                                   | Version: v5.1.4+ <br />Default: (empty) <br />Applications: API                                                                          |
| `FOOTER_GITHUB_LINK`             | Github repository. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719).                                                                                                                          | Version: v4.1.6+ <br />Default: `https://github.com/blockscout/blockscout` <br />Applications: API                                       |
| `FOOTER_LINK_TO_OTHER_EXPLORERS` | true/false. If true, links to other explorers are added in the footer.                                                                                                                                                  | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API                                                                          |
| `FOOTER_OTHER_EXPLORERS`         | The list of alternative explorers.                                                                                                                                                                                      |                                                                                                                                          |


# Backend ENVs: Chain Specific
Source: https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific

ENVS for specific chains and rollups

## Chain Specific ENVs

The following ENVs are specific to different types of chains and rollups. To use these specific variables you will also need to set the `CHAIN_TYPE` variable to the appropriate value.

| Variable    | Description                                                             | Parameters                                                                 |
| ----------- | ----------------------------------------------------------------------- | -------------------------------------------------------------------------- |
| CHAIN\_TYPE | Specifies the model of data and enables fetchers specific to the chain. | Version: v5.3.0+ <br />Default: `default` <br />Applications: API, Indexer |

### Runtime vs Compile-time Chain Types

<Warning>
  Prior to v8.0.0, updating `CHAIN_TYPE` variable required recompilation. Starting with v8.0.0, many chain types can be configured at runtime.
</Warning>

#### Runtime-Configurable Chain Types

These chain types can be configured by simply setting an environment variable with the standard image:

* `default` (standard EVM chain)
* `neon`
* `stability`
* `blackfort`
* `shibarium`

**Example:**

```swift theme={null}
docker run -e CHAIN_TYPE=shibarium ghcr.io/blockscout/blockscout:latest
```

#### Compile-time Chain Types

These specialized chain types still require recompilation and dedicated images:

* `ethereum`
* `optimism`
* `optimism-celo` (Celo on OP Stack)
* `arbitrum`
* `polygon_zkevm`
* `rsk`
* `scroll`
* `suave`
* `zetachain`
* `filecoin`

**Example:**

```sh theme={null}
docker run -e CHAIN_TYPE=optimism ghcr.io/blockscout/blockscout-optimism:latest
```

<Info>
  You can browse all available image variants in the [Blockscout GitHub Packages repository](https://github.com/orgs/blockscout/packages). Each image variant includes specific tags and documentation for deployment options.
</Info>

## Time format

Can be set in format `1h` for 1 hour, `1m` for 1 minute, `1s` or `1` for 1 second, `1ms` for 1 millisecond

<Warning>
  ***Note*** **: Before release 5.1.2, all environment variables of time format supported only integers in seconds (without dimensions) as values.**
</Warning>

## Ethereum Management

| Variable                                                    | Description                                                                                                                                                                                                                                                                                                                                                      | Parameters                                                                          |
| ----------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| `INDEXER_BEACON_RPC_URL`                                    | Beacon Chain RPC endpoint used to fetch blob sidecars. Required if `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` is defined. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                                                                  | Version: v6.2.0+ <br />Default: `http://localhost:5052` <br />Applications: Indexer |
| `INDEXER_DISABLE_BEACON_BLOB_FETCHER`                       | If `true` the Beacon data blobs fetcher won't be started, new transaction and block fields will still be extracted. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                                                                                  | Version: v6.2.0+ <br />Default: `false` <br />Applications: Indexer                 |
| `INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION`                 | Slot duration in the Beacon Chain in seconds. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168). Required if `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` is not empty and L1 is neither Mainnet, Sepolia, Holesky.                                                                                                             | Version: v6.2.0+ <br />Default: `12` <br />Applications: Indexer                    |
| `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT`                | Any past finalized Beacon Chain slot number. Used as reference for blob inclusion slot calculations. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168). Required if `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` is not empty and L1 is neither Mainnet, Sepolia, Holesky.                                                      | Version: v6.2.0+ <br />Default: `8000000` <br />Applications: Indexer               |
| `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP`           | UTC timestamp of the Beacon Chain slot specified in `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT`. Used as reference for blob inclusion slot calculations. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168). Required if `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` is not empty and L1 is neither Mainnet, Sepolia, Holesky. | Version: v6.2.0+ <br />Default: `1702824023` <br />Applications: Indexer            |
| `INDEXER_BEACON_BLOB_FETCHER_START_BLOCK`                   | Beacon Chain blob fetcher start block. On start-up, indexer will only look for missed blobs beyond this block number. It's recommended to set this block to the first block after the Dencun hardfork. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                               | Version: v6.2.0+ <br />Default: `19200000` <br />Applications: Indexer              |
| `INDEXER_BEACON_BLOB_FETCHER_END_BLOCK`                     | Beacon Chain blob fetcher end block. On start-up, indexer will only look for missed blobs before this block number. If set to `0`, then all recent till `latest` will be traversed. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                  | Version: v6.2.0+ <br />Default: `0` <br />Applications: Indexer                     |
| `INDEXER_DISABLE_BEACON_DEPOSIT_FETCHER`                    | If `true`, the Beacon deposit fetcher won't be started. Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                                                                                                            | Version: v9.1.0+ <br />Default: `false` <br />Applications: Indexer                 |
| `INDEXER_BEACON_DEPOSIT_FETCHER_INTERVAL`                   | The interval indicating how often deposit events should be queried. [Time format](/setup/env-variables/backend-envs-chain-specific#time-format). Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                   | Version: v9.1.0+ <br />Default: `6s` <br />Applications: Indexer                    |
| `INDEXER_BEACON_DEPOSIT_FETCHER_BATCH_SIZE`                 | The batch size specifies how many events are retrieved in a single database query. Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                                                                                 | Version: v9.1.0+ <br />Default: `1000` <br />Applications: Indexer                  |
| `INDEXER_DISABLE_BEACON_DEPOSIT_STATUS_FETCHER`             | If `true`, the Beacon deposit status fetcher won't be started. Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                                                                                                     | Version: v9.1.0+ <br />Default: `false` <br />Applications: Indexer                 |
| `INDEXER_BEACON_DEPOSIT_STATUS_FETCHER_EPOCH_DURATION`      | Epoch duration in the Beacon chain in seconds. Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                                                                                                                     | Version: v9.1.0+ <br />Default: `384` <br />Applications: Indexer                   |
| `INDEXER_BEACON_DEPOSIT_STATUS_FETCHER_REFERENCE_TIMESTAMP` | Any past finalized Beacon Chain epoch UTC timestamp. Used as reference for status fetcher scheduling. Implemented in [#12985](https://github.com/blockscout/blockscout/pull/12985).                                                                                                                                                                              | Version: v9.1.0+ <br />Default: `1722024023` <br />Applications: Indexer            |

## Rootstock Management

| Variable                                       | Description                                                                                                                                                                                                                                                            | Parameters                                                          |
| ---------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| `ROOTSTOCK_REMASC_ADDRESS`                     | The address hash of remasc address on Rootstock chain. Implemented in [#8542](https://github.com/blockscout/blockscout/pull/8542).                                                                                                                                     | Version: v5.3.0+ <br />Default: (empty) <br />Applications: API     |
| `ROOTSTOCK_BRIDGE_ADDRESS`                     | The address hash of bridge address on Rootstock chain. Implemented in [#8542](https://github.com/blockscout/blockscout/pull/8542).                                                                                                                                     | Version: v5.3.0+ <br />Default: (empty) <br />Applications: API     |
| `INDEXER_DISABLE_ROOTSTOCK_DATA_FETCHER`       | If `true` the fetcher of Rootstock specific fields for blocks that are already in the database won't be started, fields from new blocks will be extracted. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                 | Version: v5.3.2+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_INTERVAL`      | The interval between fetching the next `INDEXER_ROOTSTOCK_DATA_FETCHER_DB_BATCH_SIZE` blocks from the database and the node, used to configure the load on the database and JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742). | Version: v5.3.2+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_BATCH_SIZE`    | The number of requests in one JSON-RPC batch request, used to configure the load or RPS on JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                                  | Version: v5.3.2+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_CONCURRENCY`   | The number of simultaneous requests to the JSON-RPC node, used to configure the load or RPS on JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                              | Version: v5.3.2+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_DB_BATCH_SIZE` | The number of blocks fetched from the database in one database query. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                                                                      | Version: v5.3.2+ <br />Default: (empty) <br />Applications: Indexer |

## Scroll management

| Variable                                           | Description                                                                                                                                                                                                                                                       | Parameters                                                                |
| -------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------- |
| `INDEXER_SCROLL_L1_RPC`                            | The RPC endpoint for L1 used to fetch Deposit and Withdrawal messages. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                              | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_CHAIN_CONTRACT`                 | The address of ScrollChain contract on L1. Used to fetch batch and bundle events. Implemented in [#10819](https://github.com/blockscout/blockscout/pull/10819).                                                                                                   | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_BATCH_START_BLOCK`              | The number of a start block on L1 to index L1 batches and bundles. If the table of batches is not empty, the process will continue indexing from the last indexed batch. Implemented in [#10819](https://github.com/blockscout/blockscout/pull/10819).            | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` | Defines a URL to Blockscout Blobs API to retrieve L1 blobs from that. Example for Sepolia: `https://eth-sepolia.blockscout.com/api/v2/blobs`. Implemented in [#12294](https://github.com/blockscout/blockscout/pull/12294).                                       | Version: v8.1.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_MESSENGER_CONTRACT`             | The address of L1 Scroll Messenger contract on L1 used to fetch Deposit and Withdrawal messages. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                    | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_MESSENGER_START_BLOCK`          | The number of a start block on L1 to index L1 bridge messages. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L1 message. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484). | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L2_MESSENGER_CONTRACT`             | The address of L2 Scroll Messenger contract on L2 used to fetch Deposit and Withdrawal messages. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                    | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L2_MESSENGER_START_BLOCK`          | The number of a start block on L2 to index L2 bridge messages. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L2 message. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484). | Version: v6.9.0+ <br />Default: `FIRST_BLOCK` <br />Applications: Indexer |
| `INDEXER_SCROLL_L2_GAS_ORACLE_CONTRACT`            | The address of L1 Gas Oracle contract on L2. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                        | Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer       |
| `INDEXER_SCROLL_L1_ETH_GET_LOGS_RANGE_SIZE`        | Block range size for eth\_getLogs request in Scroll indexer modules for Layer 1. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                    | Version: v6.9.0+ <br />Default: `250` <br />Applications: Indexer         |
| `INDEXER_SCROLL_L2_ETH_GET_LOGS_RANGE_SIZE`        | Block range size for eth\_getLogs request in Scroll indexer modules for Layer 2. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                    | Version: v6.9.0+ <br />Default: `1000` <br />Applications: Indexer        |
| `SCROLL_L2_CURIE_UPGRADE_BLOCK`                    | L2 block number of the Curie upgrade. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                               | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_SCALAR_INIT`                            | Initial value for `scalar` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                               | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_OVERHEAD_INIT`                          | Initial value for `overhead` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                             | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_COMMIT_SCALAR_INIT`                     | Initial value for `commit_scalar` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                        | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_BLOB_SCALAR_INIT`                       | Initial value for `blob_scalar` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                          | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_BASE_FEE_INIT`                          | Initial value for `l1_base_fee` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                          | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |
| `SCROLL_L1_BLOB_BASE_FEE_INIT`                     | Initial value for `l1_blob_base_fee` parameter. Implemented in [#10484](https://github.com/blockscout/blockscout/pull/10484).                                                                                                                                     | Version: v6.9.0+ <br />Default: `0` <br />Applications: API               |

## Shibarium Management

| Variable                                          | Description                                                                                                                                                                                                                                                                                                | Parameters                                                          |
| ------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| `INDEXER_SHIBARIUM_L1_RPC`                        | The RPC endpoint for L1 used to fetch deposit or withdrawal events. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                                                            | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_START_BLOCK`                | The number of start block on L1 to index L1 events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L1 event. If empty or not defined, the L1 events are not handled. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929). | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_DEPOSIT_MANAGER_CONTRACT`   | The address of DepositManagerProxy contract on L1 used to fetch BONE token deposits. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                          | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_ETHER_PREDICATE_CONTRACT`   | The address of EtherPredicateProxy contract on L1 used to fetch ETH deposits and withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                 | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_ERC20_PREDICATE_CONTRACT`   | The address of ERC20PredicateProxy contract on L1 used to fetch ERC20 token deposits and withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                         | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_ERC721_PREDICATE_CONTRACT`  | The address of ERC721PredicateProxy contract on L1 used to fetch ERC721 token deposits and withdrawals. Optional for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                       | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_ERC1155_PREDICATE_CONTRACT` | The address of ERC1155PredicateProxy contract on L1 used to fetch ERC1155 token deposits and withdrawals. Optional for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                     | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L1_WITHDRAW_MANAGER_CONTRACT`  | The address of WithdrawManagerProxy contract on L1 used to fetch BONE token withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                      | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L2_START_BLOCK`                | The number of start block on L2 to index L2 events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L2 event. If empty or not defined, the L2 events are not handled. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929). | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L2_CHILD_CHAIN_CONTRACT`       | The address of ChildChain contract on L2 used to fetch BONE token deposits. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                   | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L2_WETH_CONTRACT`              | The address of WETH contract on L2 used to fetch ETH deposits and withdrawals. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_SHIBARIUM_L2_BONE_WITHDRAW_CONTRACT`     | The address of a contract which emits `Withdraw` event on L2. Used to fetch BONE token withdrawals. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                           | Version: v6.1.0+ <br />Default: (empty) <br />Applications: Indexer |

## Polygon zkEVM Rollup Management

| Variable                                          | Description                                                                                                                                                                                                                                                                                                                                                           | Parameters                                                          |
| ------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| `INDEXER_POLYGON_ZKEVM_BATCHES_ENABLED`           | Enables Polygon zkEVM batches fetcher. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                                    | Version: v5.3.1+ <br />Default: `false` <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_BATCHES_CHUNK_SIZE`        | The number of Polygon zkEVM batches in one chunk when reading them from RPC. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                              | Version: v5.3.1+ <br />Default: `20` <br />Applications: Indexer    |
| `INDEXER_POLYGON_ZKEVM_BATCHES_RECHECK_INTERVAL`  | The latest batch rechecking interval, seconds. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                            | Version: v5.3.1+ <br />Default: `60` <br />Applications: Indexer    |
| `INDEXER_POLYGON_ZKEVM_BATCHES_IGNORE`            | Comma-separated list of batch numbers that should be ignored by the fetcher. Implemented in [#12387](https://github.com/blockscout/blockscout/pull/12387).                                                                                                                                                                                                            | Version: v9.0.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_RPC`                    | The RPC endpoint for L1 used to fetch Deposit or Withdrawal bridge events. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                                                                | Version: v6.2.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK`     | The number of a start block on L1 to index L1 bridge events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L1 event. If empty or not defined, the L1 events are not handled. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                   | Version: v6.2.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_CONTRACT`        | The address of PolygonZkEVMBridgeV2 contract on L1 used to fetch L1 bridge events. Required for L1 bridge events indexing. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                | Version: v6.2.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NETWORK_ID`      | L1 Network ID in terms of Polygon zkEVM bridge (0 = Ethereum Mainnet, 1 = Polygon zkEVM, 2 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                   | Version: v6.4.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_ROLLUP_INDEX`    | L1 Rollup index in terms of Polygon zkEVM bridge (0 = Polygon zkEVM, 1 = Astar zkEVM, etc.). Not defined if L1 is Ethereum Mainnet. Required if L1 is not Ethereum Mainnet and `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637). | Version: v6.4.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NATIVE_SYMBOL`   | The symbol of the native coin on L1 to display it in the table of the bridge Deposits and Withdrawals on UI. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                              | Version: v6.2.0+ <br />Default: `ETH` <br />Applications: Indexer   |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NATIVE_DECIMALS` | The number of decimals to correctly display an amount of native coins for some Deposit or Withdrawal bridge operations on UI. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                             | Version: v6.2.0+ <br />Default: `18` <br />Applications: Indexer    |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK`     | The number of a start block on L2 to index L2 bridge events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L2 event. If empty or not defined, the L2 events are not handled. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                   | Version: v6.2.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_CONTRACT`        | The address of PolygonZkEVMBridgeV2 contract on L2 used to fetch L2 bridge events. Required for L2 bridge events indexing. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                | Version: v6.2.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_NETWORK_ID`      | L2 Network ID in terms of Polygon zkEVM bridge (1 = Polygon zkEVM, 2 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                                         | Version: v6.4.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_ROLLUP_INDEX`    | L2 Rollup index in terms of Polygon zkEVM bridge (0 = Polygon zkEVM, 1 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                                       | Version: v6.4.0+ <br />Default: (empty) <br />Applications: Indexer |

## Optimism Rollup Management

<Info>
  Supported together with ENV setting `CHAIN_TYPE=optimism`
</Info>

| Variable                                                           | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Parameters                                                                                               |
| ------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------- |
| `INDEXER_OPTIMISM_L1_RPC`                                          | The RPC endpoint for L1 used to fetch transaction batches, dispute games, output roots, deposits, or withdrawal events. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                                                                           | Version: v6.3.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_SYSTEM_CONFIG_CONTRACT`                       | The address of `SystemConfig` contract on L1 required for almost all Optimism fetchers. Implemented in [#10199](https://github.com/blockscout/blockscout/pull/10199).                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v6.8.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL`               | Defines a URL to Blockscout Blobs API to retrieve L1 blobs from that. Example for Sepolia: `https://eth-sepolia.blockscout.com/api/v2/blobs`. Implemented in [#9571](https://github.com/blockscout/blockscout/pull/9571).                                                                                                                                                                                                                                                                                                                                                     | Version: v6.3.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_BATCH_CELESTIA_BLOBS_API_URL`                 | Defines a URL to Celestia blobs indexer to retrieve L1 blobs from that. Example: `http://example.com/api/v1/celestia/blob`. Implemented in [#10199](https://github.com/blockscout/blockscout/pull/10199).                                                                                                                                                                                                                                                                                                                                                                     | Version: v6.8.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_BATCH_EIGENDA_BLOBS_API_URL`                  | Defines a URL to DA indexer supporting EigenDA layer to retrieve L1 blobs from that. Example: `https://da-indexer-dev.k8s-prod-3.blockscout.com/api/v1/eigenda/v2/blobs`. Implemented in [#13709](https://github.com/blockscout/blockscout/pull/13709).                                                                                                                                                                                                                                                                                                                       | Version: v10.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L1_BATCH_EIGENDA_PROXY_BASE_URL`                 | Defines a URL to EigenDA proxy node which is used by the DA indexer (planned to be optional in the future). Example for MegaETH: `http://megaeth-eigenda-proxy.node.blockscout.com:3100`. Implemented in [#13709](https://github.com/blockscout/blockscout/pull/13709).                                                                                                                                                                                                                                                                                                       | Version: v10.0.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L1_BATCH_ALT_DA_SERVER_URL`                      | Defines a URL to Alt-DA server to retrieve L1 data from that. Example for Redstone: `https://da.redstonechain.com/get`. Implemented in [#13179](https://github.com/blockscout/blockscout/pull/13179).                                                                                                                                                                                                                                                                                                                                                                         | Version: v9.2.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_BATCH_BLOCKS_CHUNK_SIZE`                      | Blocks chunk size to send batch RPC requests. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                                                                                                                                                     | Version: v6.3.0+ <br />Default: `4` <br />Applications: Indexer                                          |
| `INDEXER_OPTIMISM_L2_BATCH_GENESIS_BLOCK_NUMBER`                   | L2 genesis block number. This is the first block of Optimism BedRock upgrade. Equals to 0 if the new chain starts being already upgraded. The block number can be found at [superchain registry](https://github.com/ethereum-optimism/superchain-registry/tree/main/superchain/configs). [Example](https://github.com/ethereum-optimism/superchain-registry/blob/main/superchain/configs/mainnet/op.yaml). Implemented in [#9260](https://github.com/blockscout/blockscout/pull/9260).                                                                                        | Version: v6.3.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_OUTPUT_ORACLE_CONTRACT`                       | The address of `L2OutputOracle` contract on L1 used to fetch output roots. Required for output roots indexing. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                                                                                    | Version: v6.3.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L1_DEPOSITS_TRANSACTION_TYPE`                    | Defines OP Deposit transaction type (numeric value) which is needed for correct L2 transaction hash calculation by the Deposits indexing module. Implemented in [#10674](https://github.com/blockscout/blockscout/pull/10674).                                                                                                                                                                                                                                                                                                                                                | Version: v6.9.0+ <br />Default: `126` <br />Applications: Indexer                                        |
| `INDEXER_OPTIMISM_L2_WITHDRAWALS_START_BLOCK`                      | The number of start block on L2 to index withdrawals. If the table of withdrawals is not empty, the process will continue indexing from the last indexed withdrawal. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                              | Version: v6.3.0+ <br />Default: `1` <br />Applications: Indexer                                          |
| `INDEXER_OPTIMISM_L2_MESSAGE_PASSER_CONTRACT`                      | The address of `L2ToL1MessagePasser` contract on L2 to index withdrawals. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                                                                                                                         | Version: v6.3.0+ <br />Default: `0x4200000000000000000000000000000000000016` <br />Applications: Indexer |
| `INDEXER_OPTIMISM_L1_ETH_GET_LOGS_RANGE_SIZE`                      | Block range size for eth\_getLogs request in OP indexer modules for Layer 1. Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v6.10.0+ <br />Default: `250` <br />Applications: Indexer                                       |
| `INDEXER_OPTIMISM_L2_ETH_GET_LOGS_RANGE_SIZE`                      | Block range size for eth\_getLogs request in OP indexer modules for Layer 2. Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                                                                                                                                    | Version: v6.10.0+ <br />Default: `250` <br />Applications: Indexer                                       |
| `INDEXER_OPTIMISM_BLOCK_DURATION`                                  | Block time in seconds for the OP chain. Used by the indexer modules. Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                                                                                                                                            | Version: v6.10.0+ <br />Default: `2` <br />Applications: Indexer                                         |
| `INDEXER_OPTIMISM_L1_PORTAL_CONTRACT`                              | Optional. The address of `OptimismPortal` contract on L1 used to fetch deposit and withdrawal events. Used as a fallback address (when it cannot be read from the `SystemConfig` contract) for deposit and withdrawal events indexing. Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                          | Version: v6.10.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L1_START_BLOCK`                                  | Optional. The number of L1 block from which the logs (events) scanning should start by the indexer. Used as a fallback number (when it cannot be read from the `SystemConfig` contract). Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                        | Version: v6.10.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L1_BATCH_INBOX`                                  | Optional. The inbox address to index transaction batches on L1. Used as a fallback address (when it cannot be read from the `SystemConfig` contract). Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                                                           | Version: v6.10.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L1_BATCH_SUBMITTER`                              | Optional. The batch submitter address to index transaction batches on L1. Used as a fallback address (when it cannot be read from the `SystemConfig` contract). Implemented in [#11073](https://github.com/blockscout/blockscout/pull/11073).                                                                                                                                                                                                                                                                                                                                 | Version: v6.10.0+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L2_HOLOCENE_TIMESTAMP`                           | Holocene upgrade L2 block timestamp. If not defined, EIP-1559's denominator and multiplier are taken from `EIP_1559_BASE_FEE_MAX_CHANGE_DENOMINATOR` and `EIP_1559_ELASTICITY_MULTIPLIER` envs correspondingly. Implemented in [#11355](https://github.com/blockscout/blockscout/pull/11355).                                                                                                                                                                                                                                                                                 | Version: v6.10.1+ <br />Default: (empty) <br />Applications: Indexer                                     |
| `INDEXER_OPTIMISM_L2_HOLOCENE_BLOCKS_CHUNK_SIZE`                   | Max number of blocks in `eth_getBlockByNumber` batch request. Implemented in [#11355](https://github.com/blockscout/blockscout/pull/11355).                                                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v6.10.1+ <br />Default: `25` <br />Applications: Indexer                                        |
| `INDEXER_OPTIMISM_L2_ISTHMUS_TIMESTAMP`                            | Isthmus upgrade L2 block timestamp. Needed for operator fee determining. If set to `0`, the Isthmus is assumed to be active from genesis block. Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                 | Version: v9.2.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `INDEXER_OPTIMISM_L2_JOVIAN_TIMESTAMP`                             | Jovian upgrade L2 block timestamp. If set to `0`, the Jovian is assumed to be active from genesis block. Implemented in [#13538](https://github.com/blockscout/blockscout/pull/13538).                                                                                                                                                                                                                                                                                                                                                                                        | Version: v9.3.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `INDEXER_OPTIMISM_L2_INTEROP_START_BLOCK`                          | Defines a start block number for indexing interop messages (usually `0`). If not defined, the indexing is turned off. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                                                                           | Version: v8.0.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_OPTIMISM_L2_INTEROP_BLOCKS_CHUNK_SIZE`                    | Adjusts blocks chunk size when indexing failed relay transactions. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: `4` <br />Applications: Indexer                                          |
| `INDEXER_OPTIMISM_INTEROP_PRIVATE_KEY`                             | 32-byte private key in form of `0x...` string. Required and used to `secp256k1` sign data being sent to `/api/v2/import/optimism/interop/` remote API endpoint. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                                 | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `INDEXER_OPTIMISM_INTEROP_CONNECT_TIMEOUT`                         | Timeout in seconds for establishing HTTP connection to `/api/v2/import/optimism/interop/` and `/api/v2/optimism/interop/public-key` remote API endpoints. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                                       | Version: v8.0.0+ <br />Default: `8` <br />Applications: API, Indexer                                     |
| `INDEXER_OPTIMISM_INTEROP_RECV_TIMEOUT`                            | Timeout in seconds for receiving HTTP response from `/api/v2/import/optimism/interop/` or `/api/v2/optimism/interop/public-key` API endpoint. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                                                   | Version: v8.0.0+ <br />Default: `10` <br />Applications: API, Indexer                                    |
| `INDEXER_OPTIMISM_INTEROP_EXPORT_EXPIRATION_DAYS`                  | Limits the number of incomplete messages being sent through API to remote instances. The source or relay transactions older than this number of days (starting from the latest block) won't be considered by the handler of incomplete messages. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                | Version: v8.0.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_OPTIMISM_CHAINSCOUT_API_URL`                              | URL to Chainscout API to get instance info by chain ID. Must be omitted for local development. For production must be `https://chains.blockscout.com/api/chains/`. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903).                                                                                                                                                                                                                                                                                                                              | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `INDEXER_OPTIMISM_CHAINSCOUT_FALLBACK_MAP`                         | Defines `chain_id -> instance_url` map, for example: `{"10": "https://optimism.blockscout.com/", "8453": "https://base.blockscout.com/"}`. Supports extended format like `{"123": {"api": "https://test.blockscout.com:4000/", "ui": "https://test.blockscout.com:3000/"}}` (when backend and frontend have different URLs). Quotes usually are escaped when defining in config file, e.g.: `INDEXER_OPTIMISM_CHAINSCOUT_FALLBACK_MAP="{\"420120000\":\"http://host.docker.internal:4100/\"}"`. Implemented in [#11903](https://github.com/blockscout/blockscout/pull/11903). | Version: v8.0.0+ <br />Default: (empty) <br />Applications: API, Indexer                                 |
| `INDEXER_OPTIMISM_MULTICHAIN_BATCH_SIZE`                           | Max number of items sent to the Multichain service in one batch. Implemented in [#12387](https://github.com/blockscout/blockscout/pull/12387).                                                                                                                                                                                                                                                                                                                                                                                                                                | Version: v9.0.0+ <br />Default: `100` <br />Applications: Indexer                                        |
| `INDEXER_DISABLE_OPTIMISM_INTEROP_MULTICHAIN_EXPORT`               | Disables exporting of interop messages to Multichain service. Implemented in [#13051](https://github.com/blockscout/blockscout/pull/13051).                                                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v9.1.0+ <br />Default: `true` <br />Applications: Indexer                                       |
| `INDEXER_OPTIMISM_OPERATOR_FEE_QUEUE_BATCH_SIZE`                   | Batch size for OP operator fee fetcher. Defines max number of transactions handled per batch. Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                                                                   | Version: v9.2.0+ <br />Default: `100`<br />Applications: Indexer                                         |
| `INDEXER_OPTIMISM_OPERATOR_FEE_QUEUE_CONCURRENCY`                  | Concurrency for OP operator fee fetcher. Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Version: v9.2.0+ <br />Default: `3`<br />Applications: Indexer                                           |
| `INDEXER_OPTIMISM_OPERATOR_FEE_QUEUE_ENQUEUE_BUSY_WAITING_TIMEOUT` | Timeout before new attempt to append item to OP operator fee fetcher queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                   | Version: v9.2.0+ <br />Default: `1s`<br />Applications: Indexer                                          |
| `INDEXER_OPTIMISM_OPERATOR_FEE_QUEUE_MAX_QUEUE_SIZE`               | Maximum size of OP operator fee fetcher queue. Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Version: v9.2.0+ <br />Default: `1000`<br />Applications: Indexer                                        |
| `INDEXER_OPTIMISM_OPERATOR_FEE_QUEUE_INIT_QUERY_LIMIT`             | Limit of the init query for processing the OP operator fee fetcher queue. Implemented in [#13139](https://github.com/blockscout/blockscout/pull/13139).                                                                                                                                                                                                                                                                                                                                                                                                                       | Version: v9.2.0+ <br />Default: `1000`<br />Applications: Indexer                                        |

## zkSync Rollup Management

<Info>
  Supported together with setting `CHAIN_TYPE=zksync`
</Info>

| Variable                                         | Description                                                                                                                                                     | Parameters                                                          |
| ------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| `INDEXER_ZKSYNC_BATCHES_ENABLED`                 | Enables zkSync batches fetcher. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                                     | Version: v6.3.0+ <br />Default: `false` <br />Applications: Indexer |
| `INDEXER_ZKSYNC_BATCHES_CHUNK_SIZE`              | The number of RPC calls in one request when reading data from RPC. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                  | Version: v6.3.0+ <br />Default: `50` <br />Applications: Indexer    |
| `INDEXER_ZKSYNC_NEW_BATCHES_MAX_RANGE`           | Maximum amount of batches requested if Blockscout does not have all batches synced. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080). | Version: v6.3.0+ <br />Default: `50` <br />Applications: Indexer    |
| `INDEXER_ZKSYNC_NEW_BATCHES_RECHECK_INTERVAL`    | The latest batch rechecking interval, seconds. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                      | Version: v6.3.0+ <br />Default: `60` <br />Applications: Indexer    |
| `INDEXER_ZKSYNC_L1_RPC`                          | The RPC endpoint for L1 used to fetch status of batches. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                            | Version: v6.3.0+ <br />Default: (empty) <br />Applications: Indexer |
| `INDEXER_ZKSYNC_BATCHES_STATUS_RECHECK_INTERVAL` | The batches status rechecking interval, seconds. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                    | Version: v6.3.0+ <br />Default: `50` <br />Applications: Indexer    |

## Arbitrum Management

<Info>
  Supported together with setting `CHAIN_TYPE=arbitrum`
</Info>

| Variable                                                           | Description                                                                                                                                                                                                                                                                                                                                                                                                    | Parameters                                                                                               |
| ------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------- |
| `INDEXER_ARBITRUM_ARBSYS_CONTRACT`                                 | The address of ArbSys contract on the rollup. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                      | Version: v6.7.0+ <br />Default: `0x0000000000000000000000000000000000000064` <br />Applications: Indexer |
| `INDEXER_ARBITRUM_NODE_INTERFACE_CONTRACT`                         | The address of NodeInterface contract on the rollup. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                               | Version: v6.8.0+ <br />Default: `0x00000000000000000000000000000000000000C8` <br />Applications: Indexer |
| `INDEXER_ARBITRUM_L1_RPC`                                          | The RPC endpoint for L1 used to fetch transaction batches, block confirmations, and cross-chain messages. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                          | Version: v6.7.0+ <br />Default: empty <br />Applications: Indexer                                        |
| `INDEXER_ARBITRUM_L1_RPC_CHUNK_SIZE`                               | The number of RPC calls in one request when reading data from RPC. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                 | Version: v6.7.0+ <br />Default: `20` <br />Applications: Indexer                                         |
| `INDEXER_ARBITRUM_L1_RPC_HISTORICAL_BLOCKS_RANGE`                  | The block range size for the eth\_getLogs request. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                 | Version: v6.7.0+ <br />Default: `1000` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_L1_ROLLUP_CONTRACT`                              | The Arbitrum Rollup contract address on L1. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                        | Version: v6.7.0+ <br />Default: empty <br />Applications: Indexer                                        |
| `INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK`                            | The block number where the Arbitrum rollup contract has been deployed. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                             | Version: v6.7.0+ <br />Default: `1` <br />Applications: Indexer                                          |
| `INDEXER_ARBITRUM_L1_COMMON_START_BLOCK`                           | The block number at which synchronization will commence. It will proceed in both directions: discovering new batches up to the chain head, and historical batches until `INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK`. If omitted, the synchronization starts from the latest block. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                     | Version: v6.7.0+ <br />Default: `latest block` <br />Applications: Indexer                               |
| `INDEXER_ARBITRUM_L1_FINALIZATION_THRESHOLD`                       | The number of blocks below the blockchain head that are considered not yet finalized in environments where the settlement layer is another rollup, or when the L1 node does not support safe block retrieval. Implemented in [#10482](https://github.com/blockscout/blockscout/pull/10482).                                                                                                                    | Version: v6.8.0+ <br />Default: `1000` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_ROLLUP_CHUNK_SIZE`                               | The number of RPC calls in one request when reading data from RPC. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                 | Version: v6.7.0+ <br />Default: `20` <br />Applications: Indexer                                         |
| `INDEXER_ARBITRUM_BRIDGE_MESSAGES_TRACKING_ENABLED`                | Enables monitoring on L1 of cross-chain messages directed to L2 and catchup on L2 of historical cross-chain messages. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                              | Version: v6.7.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_MISSED_MESSAGES_RECHECK_INTERVAL`                | Interval to re-check on the rollup historical messages directed to and from the rollup, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                | Version: v6.7.0+ <br />Default: `3600` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_MISSED_MESSAGES_BLOCKS_DEPTH`                    | Amount of L2 blocks to revisit to identify historical cross-chain messages in the messages catchup task. Implemented in [#10374](https://github.com/blockscout/blockscout/pull/10374).                                                                                                                                                                                                                         | Version: v6.8.0+ <br />Default: `10000` <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_TRACKING_MESSAGES_ON_L1_RECHECK_INTERVAL`        | Interval to re-check on L1 new messages directed to the rollup, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                        | Version: v6.7.0+ <br />Default: `20` <br />Applications: Indexer                                         |
| `INDEXER_ARBITRUM_MESSAGES_TRACKING_FAILURE_THRESHOLD`             | The time threshold for L1 message tracking tasks. If a task has not run successfully within this threshold, it is marked as failed and enters a cooldown period before retrying. Implemented in [#13792](https://github.com/blockscout/blockscout/pull/13792).                                                                                                                                                 | Version: v10.0.0+ <br />Default: `10m` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_MISSED_MESSAGE_IDS_RANGE`                        | Size of each message ID range inspected when discovering L1-to-L2 messages with missing L1 origination information. Implemented in [#13792](https://github.com/blockscout/blockscout/pull/13792).                                                                                                                                                                                                              | Version: v10.0.0+ <br />Default: `10000` <br />Applications: Indexer                                     |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_ENABLED`                        | Enables monitoring of transaction batches, block confirmations, and L2-to-L1 messages executions. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                  | Version: v6.7.0+ <br />Default: (empty) <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_RECHECK_INTERVAL`               | Interval to re-check on L1 new and historical batches, confirmations, and executions, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                  | Version: v6.7.0+ <br />Default: `20` <br />Applications: Indexer                                         |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_L1_FINALIZATION_CHECK_ENABLED`  | Whether L1 transactions related to batches, confirmations, and executions need to be monitored for finalization or not. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                            | Version: v6.7.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_MESSAGES_TO_BLOCKS_SHIFT`       | Difference between the message count and actual rollup block numbers in the SequencerBatchDelivered event on L1. Applicable for ArbitrumOne only. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                  | Version: v6.7.0+ <br />Default: `0` <br />Applications: Indexer                                          |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_FAILURE_THRESHOLD`              | The time threshold for transaction batch monitoring tasks. If a task has not run successfully within this threshold, it is marked as failed and enters a cooldown period before retrying. Implemented in [#12192](https://github.com/blockscout/blockscout/pull/12192).                                                                                                                                        | Version: v8.0.0+ <br />Default: `10m` <br />Applications: Indexer                                        |
| `INDEXER_ARBITRUM_MISSING_BATCHES_RANGE`                           | Size of each batch range which will be inspected for the missing batches. Since it is not expected that batches are missed often, it is OK to have this value relatively large. Implemented in [#10466](https://github.com/blockscout/blockscout/pull/10446).                                                                                                                                                  | Version: v6.8.0+ <br />Default: `10000` <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_CONFIRMATIONS_TRACKING_FINALIZED`                | Whether to choose `safe` (true) or `latest` (false) block to discover new confirmations. This setting is required to reduce latency between the actual confirmation transaction and its discovery. Recommended to have true on rollups which use Ethereum Mainnet as L1. Determines how fast new confirmations will be discovered. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312). | Version: v6.7.0+ <br />Default: `true` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_NEW_BATCHES_LIMIT`                               | The number of batches to be handled and imported at once. This is applicable for cases when dozens of batches are found in one discovery iteration, and it is necessary to import them in chunks to avoid the entire process being aborted if any errors occur. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                    | Version: v6.7.0+ <br />Default: `10` <br />Applications: Indexer                                         |
| `INDEXER_ARBITRUM_DATA_BACKFILL_ENABLED`                           | Enables a process to backfill the blocks and transaction with Arbitrum specific data. This should only be enabled for Arbitrum chains where blocks were indexed before upgrading to a version that includes Arbitrum-specific data indexing features. Implemented in [#11163](https://github.com/blockscout/blockscout/pull/11163).                                                                            | Version: v7.0.0+ <br />Default: `false` <br />Applications: Indexer                                      |
| `INDEXER_ARBITRUM_DATA_BACKFILL_UNINDEXED_BLOCKS_RECHECK_INTERVAL` | The number of L2 blocks to look back in one iteration of the backfill process. Implemented in [#11163](https://github.com/blockscout/blockscout/pull/11163).                                                                                                                                                                                                                                                   | Version: v7.0.0+ <br />Default: `120s` <br />Applications: Indexer                                       |
| `INDEXER_ARBITRUM_DATA_BACKFILL_BLOCKS_DEPTH`                      | Interval to retry the backfill task for unindexed blocks. Implemented in [#11163](https://github.com/blockscout/blockscout/pull/11163).                                                                                                                                                                                                                                                                        | Version: v7.0.0+ <br />Default: `500` <br />Applications: Indexer                                        |
| `MIGRATION_ARBITRUM_DA_RECORDS_NORMALIZATION_BATCH_SIZE`           | Specifies the number of address records processed per batch during normalization of batch-to-blob associations by moving them from arbitrum\_da\_multi\_purpose to a dedicated arbitrum\_batches\_to\_da\_blobs table. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                           | Version: v7.0.0+ <br />Default: `500` <br />Applications: Indexer                                        |
| `MIGRATION_ARBITRUM_DA_RECORDS_NORMALIZATION_CONCURRENCY`          | Specifies the number of concurrent processes used during normalization of batch-to-blob associations by moving them from arbitrum\_da\_multi\_purpose to a dedicated arbitrum\_batches\_to\_da\_blobs table. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                     | Version: v7.0.0+ <br />Default: `1` <br />Applications: Indexer                                          |

## Celo Management

<Info>
  Supported together with setting `CHAIN_TYPE=optimism-celo`

  Starting from v9.3.0, Celo runs on the OP Stack infrastructure while maintaining Celo-specific features including:

  * Epochs
  * Election rewards
  * Token duality
  * All standard Optimism features (deposits, withdrawals, batches, etc.)
</Info>

<Warning>
  **Migration Notice**: Prior to v9.3.0, Celo used `CHAIN_TYPE=celo`. This has been changed to `CHAIN_TYPE=optimism-celo` to reflect Celo's migration to the OP Stack while preserving Celo-specific functionality.

  For instances deployed before v9.3.0, you must:

  1. Update `CHAIN_TYPE` from `celo` to `optimism-celo`
  2. Use the `optimism-celo` Docker image
  3. Configure both Optimism and Celo-specific environment variables
  4. Expect heavy migrations!
</Warning>

| Variable                                             | Description                                                                                                                                                                                                                                               | Parameters                                                               |
| ---------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| `CELO_CORE_CONTRACTS`                                | JSON dictionary containing the addresses and metadata of core CELO network contracts. Read detailed description down below. Implemented in [#9713](https://github.com/blockscout/blockscout/pull/9713).                                                   | Version: v6.8.0+ <br />Default: (empty) <br />Applications: API, Indexer |
| `CELO_L2_MIGRATION_BLOCK`                            | Specifies the block number at which Celo transitioned from L1 to L2, disabling legacy L1 mechanisms (e.g., L1 epochs, old precompiles) once the migration block is indexed. Implemented in [#11949](https://github.com/blockscout/blockscout/pull/11949). | Version: v8.0.0+ <br />Applications: API, Indexer                        |
| `INDEXER_DISABLE_CELO_EPOCH_FETCHER`                 | If set to `true`, the epoch rewards fetcher will not be started. However, epoch blocks pending to fetch will still be imported into the database. Implemented in [#9944](https://github.com/blockscout/blockscout/pull/9944).                             | Version: v6.8.0+ <br />Default: `false` <br />Applications: Indexer      |
| `INDEXER_DISABLE_CELO_VALIDATOR_GROUP_VOTES_FETCHER` | If set to `true`, the validator group votes fetcher will not be started. Implemented in [#10673](https://github.com/blockscout/blockscout/pull/10673).                                                                                                    | Version: v6.9.0+ <br />Default: `false` <br />Applications: Indexer      |
| `INDEXER_CELO_VALIDATOR_GROUP_VOTES_BATCH_SIZE`      | Specifies the block range size for the `eth_getLogs` request, determining the number of blocks included between `toBlock` and `fromBlock`. Implemented in [#9944](https://github.com/blockscout/blockscout/pull/9944).                                    | Version: v6.8.0+ <br />Default: `200000` <br />Applications: Indexer     |
| `CELO_UNRELEASED_TREASURY_CONTRACT`                  | The address of the `CeloUnreleasedTreasury` core contract. Implemented in [#12373](https://github.com/blockscout/blockscout/pull/12373).                                                                                                                  | Version: v9.0.0+ <br />Default: (empty) <br />Applications: Indexer      |
| `CELO_VALIDATORS_CONTRACT`                           | The address of the `Validators` core contract. Implemented in [#12373](https://github.com/blockscout/blockscout/pull/12373).                                                                                                                              | Version: v9.0.0+ <br />Default: (empty) <br />Applications: Indexer      |
| `CELO_EPOCH_MANAGER_CONTRACT`                        | The address of the `EpochManager` core contract. Implemented in [#12373](https://github.com/blockscout/blockscout/pull/12373).                                                                                                                            | Version: v9.0.0+ <br />Default: (empty) <br />Applications: Indexer      |
| `CELO_LOCKED_GOLD_CONTRACT`                          | The address of the `LockedGold` core contract. Implemented in [#12893](https://github.com/blockscout/blockscout/pull/12893).                                                                                                                              | Version: v9.2.0+ <br />Default: (empty)<br />Applications: Indexer       |
| `CELO_ACCOUNTS_CONTRACT`                             | The address of the `Accounts` core contract. Implemented in [#12893](https://github.com/blockscout/blockscout/pull/12893).                                                                                                                                | Version: v9.2.0+ <br />Default: (empty)<br />Applications: Indexer       |
| `INDEXER_CELO_ACCOUNTS_CONCURRENCY`                  | Sets the maximum number of concurrent requests for fetching Celo accounts.                                                                                                                                                                                | Version: v9.2.0+ <br />Default: `1`<br />Applications: Indexer           |
| `INDEXER_CELO_ACCOUNTS_BATCH_SIZE`                   | Specifies the number of account addresses processed per batch during fetching.                                                                                                                                                                            | Version: v9.2.0+ <br />Default: `100`<br />Applications: Indexer         |

### Required Optimism ENVs for Celo

Since Celo runs on the OP Stack, you must also configure all applicable Optimism environment variables from the [Optimism Rollup Management](#optimism-rollup-management) section above.

<Info>
  For Celo network configurations, contract addresses, and deployment assets, refer to the official [Celo Network Config & Assets documentation](https://docs.celo.org/infra-partners/operators/run-node#network-config-&-assets).
</Info>

<Accordion title="Details on `CELO_CORE_CONTRACTS`">
  The CELO network includes several core contracts that are central to its operation. These core contracts manage various aspects of the Celo network, including its stablecoins, governance, identity, and more.

  All these contracts can be obtained by querying the `Registry` contract, which is deployed at the genesis block with the address `0x000000000000000000000000000000000000ce10`. This contract serves as a repository for the addresses of all core contracts on the Celo network.

  Fortunately, core contracts are not updated frequently, so we store information about core contracts statically under the `CELO_CORE_CONTRACTS` variable, which is a JSON object of a specified structure.

  In case the contracts are updated, maintaining the Blockscout instance will require updating the `CELO_CORE_CONTRACTS` variable and manually setting blocks for refetch (all blocks produced after the core contracts' update).

  The structure of the JSON value for the `CELO_CORE_CONTRACTS` variable is detailed in this [gist](https://gist.github.com/fedor-ivn/c77030d09bd05349710450e0fcf00a1f).

  The JSON structure may change. To assemble the `CELO_CORE_CONTRACTS` environment variable, run `mix fetch_celo_core_contracts` in the root of the Blockscout repository. This task will index the chain from block `0` to the latest block number, providing the most up-to-date values.

  The JSON structure in the gist contains two main sections: `addresses` and `events`.

  * **addresses**: This section maps contract names to the list of respective addresses and the block number at which they were updated. For example:
    * `"Accounts"`: `[{ "address": "0xed7f51a34b4e71fbe69b3091fcf879cd14bd73a9", "updated_at_block_number": 574 }]`
    * `"Election"`: `[{ "address": "0x1c3edf937cfc2f6f51784d20deb1af1f9a8655fa", "updated_at_block_number": 592 }]`
  * **events**: This section maps contract addresses to the events associated with them, including any parameters and the block numbers at which these events were emitted. For example:
    * `"EpochRewards"`: `{ "0xb10ee11244526b94879e1956745ba2e35ae2ba20": { "CarbonOffsettingFundSet": [{ "address": "0x22579ca45ee22e2e16ddf72d955d6cf4c767b0ef", "updated_at_block_number": 15049265 }] } }`
    * `"FeeHandler"`: `{ "0x90d94229623a0a38826a4a7557a6d79acde43f76": { "BurnFractionSet": [{ "updated_at_block_number": 19732579, "value": 0.7999999999999999 }] } }`
</Accordion>

## Filecoin Management

<Info>
  Supported together with setting `CHAIN_TYPE=filecoin`
</Info>

| Variable                                                    | Description                                                                                                                                                                                                                                                                                                                                  | Parameters                                                                                              |
| ----------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------- |
| `FILECOIN_NETWORK_PREFIX`                                   | Specifies the expected network prefix for Filecoin addresses. For more details, refer to the [Filecoin Spec](https://spec.filecoin.io/appendix/address/#section-appendix.address.network-prefix). Available values: `f` (for the mainnet), `t` (for testnets). Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468). | Version: v6.9.0+ <br />Default: `f` <br />Applications: API, Indexer                                    |
| `BERYX_API_TOKEN`                                           | [Beryx API](https://docs.zondax.ch/beryx-api) token, used for retrieving Filecoin native addressing information. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                                                               | Required: ✅ Version: v6.9.0+ <br />Default: (empty) <br />Applications: Indexer                         |
| `BERYX_API_BASE_URL`                                        | [Beryx API](https://docs.zondax.ch/beryx-api) base URL. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                                                                                                                        | Version: v6.9.0+ <br />Default: `https://api.zondax.ch/fil/data/v3/mainnet` <br />Applications: Indexer |
| `FILFOX_API_BASE_URL`                                       | [Filfox API](https://filfox.info/api/v1/docs/static/index.html) base URL. Implemented in [#11412](https://github.com/blockscout/blockscout/pull/11412).                                                                                                                                                                                      | Version: v7.0.0+ <br />Default: `https://filfox.info/api/v1` <br />Applications: Indexer                |
| `INDEXER_DISABLE_FILECOIN_ADDRESS_INFO_FETCHER`             | When set to `true`, Filecoin native addressing information will not be fetched, but addresses pending fetch will still be recorded in the database. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                            | Version: v6.9.0+ <br />Default: `false` <br />Applications: Indexer                                     |
| `INDEXER_FILECOIN_ADDRESS_INFO_CONCURRENCY`                 | Sets the maximum number of concurrent requests made to fetch Filecoin native addressing information. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                                                                           | Version: v6.9.0+ <br />Default: `1` <br />Applications: Indexer                                         |
| `MIGRATION_FILECOIN_PENDING_ADDRESS_OPERATIONS_BATCH_SIZE`  | Specifies the number of address records processed per batch during the backfill of pending address fetch operations. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                           | Version: v7.0.0+ <br />Default: `100` <br />Applications: Indexer                                       |
| `MIGRATION_FILECOIN_PENDING_ADDRESS_OPERATIONS_CONCURRENCY` | Specifies the number of concurrent processes used during the backfill of pending address fetch operations. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                     | Version: v7.0.0+ <br />Default: `1` <br />Applications: Indexer                                         |

## Blackfort Management

<Info>
  Supported together with setting `CHAIN_TYPE=blackfort`
</Info>

| Variable                      | Description                                                                                                                              | Parameters                                                               |
| ----------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| `BLACKFORT_VALIDATOR_API_URL` | Variable to define the URL of the Blackfort Validator API. Implemented in [#10744](https://github.com/blockscout/blockscout/pull/10744). | Version: v6.9.0+ <br />Default: (empty) <br />Applications: API, Indexer |

## Arc Management

<Info>
  Supported together with setting `CHAIN_TYPE=arc`
</Info>

| Variable                                   | Description                                                                                                                                             | Parameters                                                                                               |
| ------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------- |
| `INDEXER_ARC_NATIVE_TOKEN_DECIMALS`        | Defines the number of decimals for Arc chain native token (e.g. USDC). Implemented in [#13452](https://github.com/blockscout/blockscout/pull/13452).    | Version: v9.3.0+ <br />Default: `6` <br />Applications: Indexer                                          |
| `INDEXER_ARC_NATIVE_TOKEN_CONTRACT`        | Arc chain native token contract address. Implemented in [#13452](https://github.com/blockscout/blockscout/pull/13452).                                  | Version: v9.3.0+ <br />Default: `0x3600000000000000000000000000000000000000` <br />Applications: Indexer |
| `INDEXER_ARC_NATIVE_TOKEN_SYSTEM_CONTRACT` | Arc chain system contract address emitting `NativeCoinTransferred` event. Implemented in [#13452](https://github.com/blockscout/blockscout/pull/13452). | Version: v9.3.0+ <br />Default: `0x1800000000000000000000000000000000000000` <br />Applications: Indexer |


# Backend ENVs: Integrations
Source: https://docs.blockscout.com/setup/env-variables/backend-envs-integrations



<Info>
  The following ENVs are used for different integrations. Some work with various microservices (when the variable begins with MICROSERVICE) while others are contained within the application.

  More info on Blockscout Rust MicroServices is available in the [blockscout-rs Github Repo](https://github.com/blockscout/blockscout-rs/tree/main).
</Info>

## Time format

Can be set in format `1h` for 1 hour, `1m` for 1 minute, `1s` or `1` for 1 second, `1ms` for 1 millisecond

<Warning>
  ***Note*** **: Before release 5.1.2, all environment variables of time format supported only integers in seconds (without dimensions) as values.**
</Warning>

## Smart-contract verifier / Eth Bytecode DB

<Info>
  Connecting to the smart contract verification service
</Info>

| Variable                                                | Description                                                                                                                                                                                                                                                                               | Parameters                                                                                                 |
| ------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------- |
| `MICROSERVICE_SC_VERIFIER_ENABLED`                      | If `true`, integration with [Rust smart-contract verifier](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier) is enabled. `true` is the default value starting from version 6.4.0. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860) | Version: v5.1.3+ <br />Default: `true` <br />Applications: API                                             |
| `MICROSERVICE_SC_VERIFIER_URL`                          | URL of Rust smart-contract verifier. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860)                                                                                                                                                                           | Version: v5.1.3+ <br />Default: `https://eth-bytecode-db.services.blockscout.com/` <br />Applications: API |
| `MICROSERVICE_ETH_BYTECODE_DB_INTERVAL_BETWEEN_LOOKUPS` | Minimal time after unsuccessful check of smart contract's sources in Eth Bytecode DB. Implemented in [#7187](https://github.com/blockscout/blockscout/pull/7187).                                                                                                                         | Version: v5.1.3+ <br />Default: `10m` <br />Applications: API                                              |
| `MICROSERVICE_SC_VERIFIER_TYPE`                         | Type of smart contract microservice could be either `eth_bytecode_db` or `sc_verifier`. Implemented in [#7187](https://github.com/blockscout/blockscout/pull/7187)                                                                                                                        | Version: v5.1.3+ <br />Default: `sc_verifier` <br />Applications: API                                      |
| `MICROSERVICE_ETH_BYTECODE_DB_MAX_LOOKUPS_CONCURRENCY`  | Maximum amount of concurrent requests for fetching smart contract's sources in Eth Bytecode DB. Implemented in [#8472](https://github.com/blockscout/blockscout/pull/8472)                                                                                                                | Version: v5.3.0+ <br />Default: `10` <br />Applications: API                                               |
| `MICROSERVICE_SC_VERIFIER_API_KEY`                      | API key for verification that metadata sent to verifier microservice from a trusted source. Implemented in [#8750](https://github.com/blockscout/blockscout/pull/8750)                                                                                                                    | Version: v5.3.2+ <br />Default: (empty) <br />Applications: API                                            |

## Sol2Uml

<Info>
  Sol2Uml is a visualization tool for Solidity contracts.
</Info>

<Frame>
  <img alt="" />
</Frame>

<Frame>
  <img alt="" />
</Frame>

| Variable                                 | Description                                                                                                                                                                                                    | Parameters                                                      |
| ---------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_VISUALIZE_SOL2UML_ENABLED` | If `true`, integration with [Rust sol2uml visualizer](https://github.com/blockscout/blockscout-rs/tree/main/visualizer) is enabled. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401) | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_VISUALIZE_SOL2UML_URL`     | URL of Rust visualizer. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401)                                                                                                             | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |

## Sig-provider

<Info>
  The Sig-provider microservice is used by Blockscout to display decoded transaction data on transaction pages and to determine transaction actions
</Info>

| Variable                            | Description                                                                                                                                                                                                        | Parameters                                                      |
| ----------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------- |
| `MICROSERVICE_SIG_PROVIDER_ENABLED` | If `true`, integration with [Rust sig-provider service](https://github.com/blockscout/blockscout-rs/tree/main/sig-provider) is enabled. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541) | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_SIG_PROVIDER_URL`     | URL of Rust sig-provider service. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                       | Version: v5.1.3+ <br />Default: (empty) <br />Applications: API |

## Blockscout ENS

<Info>
  Blockscout ENS provides indexed data of domain name service for blockscout instances. [Learn more](https://github.com/blockscout/blockscout-rs/tree/main/blockscout-ens).
</Info>

| Variable                    | Description                                                                                                                                                                                                       | Parameters                                                      |
| --------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_BENS_ENABLED` | If `true`, integration with [Blockscout ENS service](https://github.com/blockscout/blockscout-rs/tree/main/blockscout-ens) is enabled. Implemented in [#8972](https://github.com/blockscout/blockscout/pull/8972) | Version: v5.4.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_BENS_URL`     | URL of Blockscout ENS service. Implemented in [#8972](https://github.com/blockscout/blockscout/pull/8972)                                                                                                         | Version: v5.4.0+ <br />Default: (empty) <br />Applications: API |

## Blockscout Account Abstraction

<Info>
  Enables the [User Ops Indexer](https://github.com/blockscout/blockscout-rs/tree/main/user-ops-indexer), a service designed to index, decode and serve user operations as per the ERC-4337 standard
</Info>

| Variable                                   | Description                                                                                                                                                                                                                         | Parameters                                                      |
| ------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_ACCOUNT_ABSTRACTION_ENABLED` | If `true`, integration with [Blockscout Account Abstraction service](https://github.com/blockscout/blockscout-rs/tree/main/user-ops-indexer) is enabled. Implemented in [#9145](https://github.com/blockscout/blockscout/pull/9145) | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_ACCOUNT_ABSTRACTION_URL`     | URL of Blockscout ENS service. Implemented in [#9145](https://github.com/blockscout/blockscout/pull/9145)                                                                                                                           | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API |

## Tx Interpreter (Summary) Service

| Variable                                          | Description                                                                                                                               | Parameters                                                      |
| ------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_TRANSACTION_INTERPRETATION_ENABLED` | If `true`, integration with Tx Interpreter Service is enabled. Implemented in [#8957](https://github.com/blockscout/blockscout/pull/8957) | Version: v5.4.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_TRANSACTION_INTERPRETATION_URL`     | URL of Tx Interpreter Service. Implemented in [#8957](https://github.com/blockscout/blockscout/pull/8957)                                 | Version: v5.4.0+ <br />Default: (empty) <br />Applications: API |

## Metadata Service

| Variable                                       | Description                                                                                                                                 | Parameters                                                      |
| ---------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_METADATA_ENABLED`                | If `true`, integration with Metadata Service is enabled. Implemented in [#9706](https://github.com/blockscout/blockscout/pull/9706)         | Version: v6.4.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_METADATA_URL`                    | URL of Metadata Service. Implemented in [#9706](https://github.com/blockscout/blockscout/pull/9706)                                         | Version: v6.4.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_METADATA_PROXY_REQUESTS_TIMEOUT` | Timeout for request forwarding from `/api/v2/proxy/metadata/`. Implemented in [#11656](https://github.com/blockscout/blockscout/pull/11656) | Version: v7.0.0+ <br />Default: `30s` <br />Applications: API   |

## Multichain Search Service

<Info>
  Multichain Search is the single point of search of the data in the all blockchains.
</Info>

| Variable                                                                            | Description                                                                                                                                                                                                                                                     | Parameters                                                                |
| ----------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------- |
| `MICROSERVICE_MULTICHAIN_SEARCH_URL`                                                | Multichain Search Service API URL. Integration is enabled, if this variable value contains valid URL. Implemented in [#11139](https://github.com/blockscout/blockscout/pull/11139)                                                                              | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer |
| `MICROSERVICE_MULTICHAIN_SEARCH_API_KEY`                                            | Multichain Search Service API key. Implemented in [#11139](https://github.com/blockscout/blockscout/pull/11139)                                                                                                                                                 | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API, Indexer |
| `MICROSERVICE_MULTICHAIN_SEARCH_ADDRESSES_CHUNK_SIZE`                               | Chunk size of addresses while exporting to Multichain Search DB. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377)                                                                                                                   | Version: v8.1.0+ <br />Default: 7000 <br />Applications: API, Indexer     |
| `MICROSERVICE_MULTICHAIN_SEARCH_TOKEN_INFO_CHUNK_SIZE`                              | Chunk size of token info while exporting to Multichain Search DB. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867)                                                                                                                  | Version: v9.0.0+ <br />Default: 1000 <br />Applications: Indexer          |
| `MICROSERVICE_MULTICHAIN_SEARCH_COUNTERS_CHUNK_SIZE`                                | Chunk size of counters while exporting to Multichain Search DB. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                                                   | Version: v9.1.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `MIGRATION_BACKFILL_MULTICHAIN_SEARCH_BATCH_SIZE`                                   | Batch size of backfilling Multichain Search Service DB. Implemented in [#11139](https://github.com/blockscout/blockscout/pull/11139)                                                                                                                            | Version: v6.10.0+ <br />Default: 10 <br />Applications: Indexer           |
| `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_FETCHER`                    | If `true`, multichain DB main (blocks, transactions, addresses) export fetcher doesn't run. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377).                                                                                       | Version: v9.0.0+ <br />Default: `false`<br />Applications: Indexer        |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_BATCH_SIZE`                         | Batch size for multichain DB main (blocks, transactions, addresses) export fetcher. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377).                                                                                               | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_CONCURRENCY`                        | Concurrency for multichain DB main (blocks, transactions, addresses) export fetcher. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377).                                                                                              | Version: v9.0.0+ <br />Default: `10`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_ENQUEUE_BUSY_WAITING_TIMEOUT`       | Timeout before new attempt to append item to multichain DB main (blocks, transactions, addresses) export queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). | Version: v9.0.0+ <br />Default: `1s`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_MAX_QUEUE_SIZE`                     | Maximum size of multichain DB main (blocks, transactions, addresses) export queue. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377).                                                                                                | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_INIT_QUERY_LIMIT`                   | Limit of the init query for processing the main export queue to the Multichain DB. Implemented in [#12822](https://github.com/blockscout/blockscout/pull/12822).                                                                                                | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_FETCHER`                | If `true`, multichain DB balances export fetcher doesn't run. Implemented in [#12580](https://github.com/blockscout/blockscout/pull/12580).                                                                                                                     | Version: v9.0.0+ <br />Default: `false`<br />Applications: Indexer        |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_BATCH_SIZE`                     | Batch size for multichain DB balances export fetcher. Implemented in [#12580](https://github.com/blockscout/blockscout/pull/12580).                                                                                                                             | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_CONCURRENCY`                    | Concurrency for multichain DB balances export fetcher. Implemented in [#12580](https://github.com/blockscout/blockscout/pull/12580).                                                                                                                            | Version: v9.0.0+ <br />Default: `10`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_ENQUEUE_BUSY_WAITING_TIMEOUT`   | Timeout before new attempt to append item to multichain DB balances export queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#12580](https://github.com/blockscout/blockscout/pull/12580).                               | Version: v9.0.0+ <br />Default: `1s`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_MAX_QUEUE_SIZE`                 | Maximum size of multichain DB balances export queue. Implemented in [#12580](https://github.com/blockscout/blockscout/pull/12580).                                                                                                                              | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_BALANCES_QUEUE_INIT_QUERY_LIMIT`               | Limit of the init query for processing the balances export queue to the Multichain DB. Implemented in [#12822](https://github.com/blockscout/blockscout/pull/12822).                                                                                            | Version: v9.0.0+ <br />Default: `1000` <br />Applications: Indexer        |
| `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_FETCHER`              | If `true`, multichain DB token info export fetcher doesn't run. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                                                                                                                   | Version: v9.0.0+ <br />Default: `false`<br />Applications: Indexer        |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_BATCH_SIZE`                   | Batch size for multichain DB token info export fetcher. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                                                                                                                           | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_CONCURRENCY`                  | Concurrency for multichain DB token info export fetcher. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                                                                                                                          | Version: v9.0.0+ <br />Default: `10`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_ENQUEUE_BUSY_WAITING_TIMEOUT` | Timeout before new attempt to append item to multichain DB token info export queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                             | Version: v9.0.0+ <br />Default: `1s`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_MAX_QUEUE_SIZE`               | Maximum size of multichain DB token info export queue. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                                                                                                                            | Version: v9.0.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_TOKEN_INFO_QUEUE_INIT_QUERY_LIMIT`             | Limit of the init query for processing the token info export queue to the Multichain DB. Implemented in [#12867](https://github.com/blockscout/blockscout/pull/12867).                                                                                          | Version: v9.0.0+ <br />Default: `1000` <br />Applications: Indexer        |
| `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_FETCHER`                | If `true`, multichain DB counters export fetcher doesn't run. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                                                     | Version: v9.1.0+ <br />Default: `false`<br />Applications: Indexer        |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_BATCH_SIZE`                     | Batch size for multichain DB counters export fetcher. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                                                             | Version: v9.1.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_CONCURRENCY`                    | Concurrency for multichain DB counters export fetcher. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                                                            | Version: v9.1.0+ <br />Default: `10`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_ENQUEUE_BUSY_WAITING_TIMEOUT`   | Timeout before new attempt to append item to multichain DB counters export queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                               | Version: v9.1.0+ <br />Default: `1s`<br />Applications: Indexer           |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_MAX_QUEUE_SIZE`                 | Maximum size of multichain DB counters export queue. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                                                              | Version: v9.1.0+ <br />Default: `1000`<br />Applications: Indexer         |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_COUNTERS_QUEUE_INIT_QUERY_LIMIT`               | Limit of the init query for processing the counters export queue to the Multichain DB. Implemented in [#13007](https://github.com/blockscout/blockscout/pull/13007).                                                                                            | Version: v9.1.0+ <br />Default: `1000` <br />Applications: Indexer        |

## TAC Operation Lifecycle Service

| Variable                                       | Description                                                                                                                                                                                          | Parameters                                                      |
| ---------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `MICROSERVICE_TAC_OPERATION_LIFECYCLE_URL`     | TAC Operation Lifecycle Service API URL. Integration is enabled, if this variable value contains valid URL. Implemented in [#12367](https://github.com/blockscout/blockscout/pull/12367)             | Version: v8.1.0+ <br />Default: (empty) <br />Applications: API |
| `MICROSERVICE_TAC_OPERATION_LIFECYCLE_ENABLED` | If `false`, TAC Operation Lifecycle Service integration is disabled despite `MICROSERVICE_TAC_OPERATION_LIFECYCLE_URL`. Implemented in [#12367](https://github.com/blockscout/blockscout/pull/12367) | Version: v8.1.0+ <br />Default: `true` <br />Applications: API  |

## Sourcify

<Info>
  Allows for contract verification via [Sourcify](https://sourcify.dev/)
</Info>

| Variable                       | Description                                                     | Parameters                                                                                                                                                      |
| ------------------------------ | --------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `SOURCIFY_INTEGRATION_ENABLED` | Enables or disables verification of contracts through Sourcify. | Version: v5.1.3+ <br />Default: `false` <br />Applications: API                                                                                                 |
| `SOURCIFY_SERVER_URL`          | URL to Sourcify backend.                                        | Version: v3.7.0+ <br />Default: `https://sourcify.dev/server` <br />Applications: API                                                                           |
| `SOURCIFY_REPO_URL`            | URL to Sourcify repository with fully verified contracts.       | Version: v3.7.0+ <br />Default: `https://repo.sourcify.dev/contracts/` Before v3.7.1: `https://repo.sourcify.dev/contracts/full_match/` <br />Applications: API |

## Tenderly

| Variable              | Description                                                                                                                                                                                                                                                                   | Parameters                                                      |
| --------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `SHOW_TENDERLY_LINK`  | if `true`, Open in Tenderly" button is displayed on the transaction page. Implemented in [#4656](https://github.com/blockscout/blockscout/pull/4656)                                                                                                                          | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API |
| `TENDERLY_CHAIN_PATH` | Chain path to the transaction in Tenderly. For instance, for transactions in xDai, Tenderly link looks like this `https://dashboard.tenderly.co/tx/xdai/0x...`, then `TENDERLY_CHAIN_PATH =/xdai.` Implemented in [#4656](https://github.com/blockscout/blockscout/pull/4656) | Version: v4.0.0+ <br />Default: (empty) <br />Applications: API |

## Datadog

<Info>
  Integration with the Datadog monitoring and analytics tools
</Info>

| Variable       | Description                                                                                     | Parameters                                                  |
| -------------- | ----------------------------------------------------------------------------------------------- | ----------------------------------------------------------- |
| `DATADOG_HOST` | Host configuration setting for [Datadog integration](https://docs.datadoghq.com/integrations/). | Version: all <br />Default: (empty) <br />Applications: API |
| `DATADOG_PORT` | Port configuration setting for [Datadog integration](https://docs.datadoghq.com/integrations/). | Version: all <br />Default: (empty) <br />Applications: API |

## Spandex

<Info>
  Spandex is a library for tracing Elixir applications
</Info>

| Variable                 | Description                                                                              | Parameters                                                  |
| ------------------------ | ---------------------------------------------------------------------------------------- | ----------------------------------------------------------- |
| `SPANDEX_BATCH_SIZE`     | [Spandex](https://github.com/spandex-project/spandex) and Datadog configuration setting. | Version: all <br />Default: (empty) <br />Applications: API |
| `SPANDEX_SYNC_THRESHOLD` | [Spandex](https://github.com/spandex-project/spandex) and Datadog configuration setting. | Version: all <br />Default: (empty) <br />Applications: API |

## Analytics

<Info>
  Variables for adding Mixpanel and/or amplitude for visitor analytics.
</Info>

| Variable            | Description                                                                                                                              | Parameters                                                                          |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| `MIXPANEL_TOKEN`    | [Mixpanel](https://mixpanel.com/) project token.                                                                                         | Needs Recompile: ☑️ Version: v5.0.0+ <br />Default: (empty) <br />Applications: API |
| `MIXPANEL_URL`      | Url to use Mixpanel with proxy ([Collection via Proxy](https://developer.mixpanel.com/docs/collection-via-a-proxy)).                     | Needs Recompile: ☑️ Version: v5.0.0+ <br />Default: (empty) <br />Applications: API |
| `AMPLITUDE_API_KEY` | [Amplitude](https://amplitude.com/) API key.                                                                                             | Needs Recompile: ☑️ Version: v5.0.0+ <br />Default: (empty) <br />Applications: API |
| `AMPLITUDE_URL`     | Url to use Amplitude with proxy ([Use Domain Proxy to Relay Events](https://www.docs.developers.amplitude.com/analytics/domain-proxy/)). | Needs Recompile: ☑️ Version: v5.0.0+ <br />Default: (empty) <br />Applications: API |

## Solidityscan

<Info>
  Enables security scoring for smart contracts
</Info>

<Frame>
  <img alt="" />
</Frame>

| Variable                   | Description                                                                                                                                                                                                                                                | Parameters                                                      |
| -------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| `SOLIDITYSCAN_PLATFORM_ID` | Internal platform id in [Solidityscan](https://apidoc.solidityscan.com/solidityscan-security-api/solidityscan-other-apis/quickscan-api-v1). Implemented in [#10473](https://github.com/blockscout/blockscout/pull/10473)                                   | Version: v6.8.0+ <br />Default: 16 <br />Applications: API      |
| `SOLIDITYSCAN_CHAIN_ID`    | Internal chain id in [Solidityscan](https://apidoc.solidityscan.com/solidityscan-security-api/solidityscan-other-apis/quickscan-api-v1). It may not match with actual chain ID. Implemented in [#8908](https://github.com/blockscout/blockscout/pull/8908) | Version: v5.3.3+ <br />Default: (empty) <br />Applications: API |
| `SOLIDITYSCAN_API_TOKEN`   | API token for usage of [Solidityscan API](https://apidoc.solidityscan.com/solidityscan-security-api/solidityscan-other-apis/quickscan-api-v1).                                                                                                             | Version: v5.3.3+ <br />Default: (empty) <br />Applications: API |

## Noves.fi

<Info>
  Adds additional transaction details such as summaries and asset flows. [More info here](https://www.blog.blockscout.com/better-blockchain-data-with-noves/).
</Info>

| Variable                | Description                                                                                                                                            | Parameters                                                                            |
| ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------- |
| `NOVES_FI_BASE_API_URL` | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) base URL. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056).   | Version: v6.1.0+ <br />Default: `https://blockscout.noves.fi` <br />Applications: API |
| `NOVES_FI_CHAIN_NAME`   | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) chain name. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056). | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API                       |
| `NOVES_FI_API_TOKEN`    | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) token. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056).      | Version: v6.1.0+ <br />Default: (empty) <br />Applications: API                       |

## MUD framework

<Info>
  [The MUD framework](https://mud.dev/introduction) provides standardized tools for data retrieval, libraries and more.
</Info>

| Variable              | Description                                                                                                                                                                                               | Parameters                                                                                |
| --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------- |
| `MUD_INDEXER_ENABLED` | If `true`, integration with [MUD](https://mud.dev/services/indexer#schemaless-indexing-with-postgresql-via-docker) is enabled. Implemented in [#9869](https://github.com/blockscout/blockscout/pull/9869) | Needs Recompile: ☑️ <br />Version: v6.6.0+ <br />Default: (empty) <br />Applications: API |
| `MUD_DATABASE_URL`    | MUD indexer DB connection URL.                                                                                                                                                                            | Version: v6.6.0+ <br />Default: value from `DATABASE_URL` <br />Applications: API         |
| `MUD_POOL_SIZE`       | MUD indexer DB `pool_size`                                                                                                                                                                                | Version: v6.6.0+ <br />Default: `50` <br />Applications: API                              |

## Xname app

<Info>
  Enables Xname app integration, which includes humanity score displayment.
</Info>

| Variable             | Description                                                                                                             | Parameters                                                                          |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| `XNAME_BASE_API_URL` | [Xname API](https://xname.app/) base URL. Implemented in [#11010](https://github.com/blockscout/blockscout/pull/11010). | Version: v6.9.2+ <br />Default: `https://gateway.xname.app` <br />Applications: API |
| `XNAME_API_TOKEN`    | [Xname API](https://xname.app/) token. Implemented in [#11010](https://github.com/blockscout/blockscout/pull/11010).    | Version: v6.9.2+ <br />Default: (empty) <br />Applications: API                     |

## Stylus contract verifier

<Info>
  Connecting to the Stylus smart contract verification service
</Info>

| Variable                           | Description                                                                                                                                                                                                                                                            | Parameters                                                       |
| ---------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------- |
| `MICROSERVICE_STYLUS_VERIFIER_URL` | URL of Stylus verifier. If set valid url and `CHAIN_TYPE=arbitrum`, integration with [Stylus verifier](https://github.com/blockscout/blockscout-rs/tree/main/stylus-verifier) is enabled. Implemented in [#11183](https://github.com/blockscout/blockscout/pull/11183) | Version: v6.10.0+ <br />Default: (empty) <br />Applications: API |


# Deprecated Backend ENVs
Source: https://docs.blockscout.com/setup/env-variables/deprecated-env-variables



<Info>
  This table is horizontally scrollable, version information is located in the last column.
</Info>

| Variable                                                                 | Description                                                                                                                                                                                                                                                                                                                                                                                                                                       | Default                                                                                       | Version  | Need recompile | Deprecated in Version |
| ------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- | -------- | -------------- | --------------------- |
| `ETHEREUM_JSONRPC_JSON_RPC_TRANSPORT`                                    | Specifies the transport for blockscout to connect to the Ethereum Node. Available transports are `http` and `ipc`. If `ipc` is selected, also set `IPC_PATH` variable. Replaced with `ETHEREUM_JSONRPC_TRANSPORT`                                                                                                                                                                                                                                 | `http`                                                                                        | v2.1.1+  |                | v3.1.0                |
| `COINMARKETCAP_PAGES`                                                    | the number of pages on coinmarketcap to list in order to find token's price                                                                                                                                                                                                                                                                                                                                                                       | 10                                                                                            | v1.3.10+ |                | v2.0.4                |
| `COIN_GECKO_ID`                                                          | CoinGecko coin id required for fetching an exchange rate                                                                                                                                                                                                                                                                                                                                                                                          | poa-network                                                                                   | v2.0.4+  |                | v2.1.0                |
| `NETWORK_ICON`                                                           | Environment variable for the main network icon or testnet icon. Two options are `_test_network_icon.html` and `_network_icon.html`                                                                                                                                                                                                                                                                                                                | \_network\_icon.html                                                                          | All      |                | v2.0.0                |
| `REWARDS_CONTRACT_ADDRESS`                                               | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA` . Replaced with `REWARDS_CONTRACT`                                                                                                                                                                                                                                                                                                              | `0xeca443e8e1ab29971a45a9c57a6a9875701698a5`                                                  | v2.0.4+  |                | v3.1.0                |
| `OMNI_BRIDGE_MEDIATOR`                                                   | An address of home OmniBridge mediator to bridge multiple tokens from Ethereum. Providing this address enables bridged tokens functionality: bridged status and link to the original token in the foreign chain.                                                                                                                                                                                                                                  | (empty)                                                                                       | v3.3.2+  |                | v3.6.0                |
| `ENABLE_1559_SUPPORT`                                                    | Enables store and display of additional fields on block and transaction according to [EIP-1559](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-1559.md)                                                                                                                                                                                                                                                                                    | false                                                                                         | v4.0.0+  |                | v4.1.0                |
| `BLOCK_COUNT_CACHE_PERIOD`                                               | time to live of blocks with consensus count cache in seconds. This var was introduced in [#1876](https://github.com/poanetwork/blockscout/pull/1876)                                                                                                                                                                                                                                                                                              | 2 hours                                                                                       | v2.0.0+  |                | v4.1.3                |
| `TXS_COUNT_CACHE_PERIOD`                                                 | Interval in seconds to restart the task, which calculates the total txs count.                                                                                                                                                                                                                                                                                                                                                                    | 2 hours                                                                                       | v1.3.9+  |                | v4.1.3                |
| `ADDRESS_COUNT_CACHE_PERIOD`                                             | time to live of cache in seconds. This var was introduced in [#2822](https://github.com/poanetwork/blockscout/pull/2822)                                                                                                                                                                                                                                                                                                                          | 2 hours                                                                                       | v2.1.1+  |                | v4.1.3                |
| `ADDRESS_SUM_CACHE_PERIOD`                                               | time to live of addresses sum (except burn address) cache in seconds. This var was introduced in [#2862](https://github.com/poanetwork/blockscout/pull/2862)                                                                                                                                                                                                                                                                                      | 1 hour                                                                                        | v2.1.1+  |                | v4.1.3                |
| `TOTAL_GAS_USAGE_CACHE_PERIOD`                                           | Interval in seconds to restart the task, which calculates the total gas usage.                                                                                                                                                                                                                                                                                                                                                                    | 2 hours                                                                                       | v3.4.0+  |                | v4.1.3                |
| `ADDRESS_TRANSACTIONS_GAS_USAGE_COUNTER_CACHE_PERIOD`                    | Interval in seconds to restart the task, which calculates gas usage at the address.                                                                                                                                                                                                                                                                                                                                                               | 30 minutes                                                                                    | v3.4.0+  |                | v4.1.3                |
| `TOKEN_HOLDERS_COUNTER_CACHE_PERIOD`                                     | Interval in seconds to restart the task, which calculates holders count of the token.                                                                                                                                                                                                                                                                                                                                                             | 1 hour                                                                                        | v3.4.0+  |                | v4.1.3                |
| `TOKEN_TRANSFERS_COUNTER_CACHE_PERIOD`                                   | Interval in seconds to restart the task, which calculates transfers count of the token.                                                                                                                                                                                                                                                                                                                                                           | 1 hour                                                                                        | v3.4.0+  |                | v4.1.3                |
| `ADDRESS_WITH_BALANCES_UPDATE_INTERVAL`                                  | Interval in seconds to restart the task, which calculates addresses with balances.                                                                                                                                                                                                                                                                                                                                                                | 30 minutes                                                                                    | v1.3.9+  |                | v4.1.3                |
| `AVERAGE_BLOCK_CACHE_PERIOD`                                             | Update of average block period cache, in seconds                                                                                                                                                                                                                                                                                                                                                                                                  | 30 minutes                                                                                    | v2.0.2+  |                | v4.1.3                |
| `MARKET_HISTORY_CACHE_PERIOD`                                            | Update of market history cache, in seconds                                                                                                                                                                                                                                                                                                                                                                                                        | 6 hours                                                                                       | v2.0.2+  |                | v4.1.3                |
| `COINGECKO_COIN_ID`                                                      | Explicitly set CoinGecko coin ID                                                                                                                                                                                                                                                                                                                                                                                                                  | (empty)                                                                                       | v3.1.2+  |                | v4.1.4                |
| `SOURCE_MODULE`                                                          | This environment variable is used to calculate the exchange rate and is specifically used by the xDai Chain. Available value is `TokenBridge`                                                                                                                                                                                                                                                                                                     | (empty)                                                                                       | v1.0.0+  |                | v4.1.4                |
| `POS_STAKING_CONTRACT`                                                   | The address of POSDAO staking contract. When provided, enables staking DApp. ValidatorSet and BlockReward contract addresses are fetched using corresponding getters.                                                                                                                                                                                                                                                                             | (empty)                                                                                       | v3.4.0+  |                | v4.1.x                |
| `POS_ETH_SUBSCRIBE_MAX_DELAY`                                            | Used by the staking DApp. The number of seconds of max delay after the latest block number arrived from eth\_subscribe. Once this time is elapsed, the staking DApp automatically switches to eth\_blockNumber which then is requested every `POS_ETH_BLOCKNUMBER_PULL_INTERVAL` milliseconds until eth\_subscribe works again.                                                                                                                   | 60                                                                                            | v3.6.0+  |                | v4.1.x                |
| `POS_ETH_BLOCKNUMBER_PULL_INTERVAL`                                      | An interval between eth\_blockNumber requests (in milliseconds) made by staking DApp to retrieve a new block number. Used when eth\_subscribe stops working.                                                                                                                                                                                                                                                                                      | 500                                                                                           | v3.6.0+  |                | v4.1.x                |
| `ENABLE_POS_STAKING_IN_MENU`                                             | Enables Staking dapp in the menu                                                                                                                                                                                                                                                                                                                                                                                                                  | false                                                                                         | v3.6.0+  |                | v4.1.x                |
| `SHOW_STAKING_WARNING`                                                   | Disables/enables announcement inside staking dapp                                                                                                                                                                                                                                                                                                                                                                                                 | false                                                                                         | v3.6.0+  |                | v4.1.x                |
| `STAKING_WARNING_MESSAGE`                                                | Message text of the announcement inside staking dapp                                                                                                                                                                                                                                                                                                                                                                                              | (empty)                                                                                       | v3.6.0+  |                | v4.1.x                |
| `ETH_OMNI_BRIDGE_MEDIATOR`                                               | An address of home OmniBridge mediator to bridge multiple tokens from Ethereum. Providing this address enables bridged tokens functionality: bridged status and link to the original token in the foreign chain.                                                                                                                                                                                                                                  | (empty)                                                                                       | v3.6.0+  |                | v4.1.x                |
| `BSC_OMNI_BRIDGE_MEDIATOR`                                               | An address of home OmniBridge mediator to bridge multiple tokens from Binance Smart Chain. Providing this address enables bridged tokens functionality: bridged status and link to the original token in the foreign chain.                                                                                                                                                                                                                       | (empty)                                                                                       | v3.6.0+  |                | v4.1.x                |
| `AMB_BRIDGE_MEDIATORS`                                                   | A comma-separated list of AMB extensions' mediators' addresses' hashes to fetch bridged tokens through those mediators.                                                                                                                                                                                                                                                                                                                           | (empty)                                                                                       | v3.6.0+  |                | v4.1.x                |
| `FOREIGN_JSON_RPC`                                                       | JSON RPC endpoint to the foreign chain in order to get metadata of bridged through Omni-bridge token. It was introduced in this PR [#3282](https://github.com/poanetwork/blockscout/pull/3282)                                                                                                                                                                                                                                                    | (empty)                                                                                       | v3.3.3+  |                | v4.1.x                |
| `BRIDGE_MARKET_CAP_UPDATE_INTERVAL`                                      | Market cap update interval for \`TokenBridge\` supply module as for TokenBridge and for OmniBridge as well, in seconds. It was introduced in this PR [#3293](https://github.com/poanetwork/blockscout/pull/3293)                                                                                                                                                                                                                                  | 30 minutes                                                                                    | v3.3.3+  |                | v4.1.x                |
| `DISABLE_BRIDGE_MARKET_CAP_UPDATER`                                      | Disables recurring consolidation of TokenBridge market cap from TokenBridge, OmniBridge and AMB extensions                                                                                                                                                                                                                                                                                                                                        | (empty)                                                                                       | v3.3.3+  |                | v4.1.x                |
| `EXTERNAL_APPS`                                                          | An array of external apps to display in Apps menu item. This var was introduced in this PR [#3184](https://github.com/poanetwork/blockscout/pull/3184) and looks like an array of JSON objects.                                                                                                                                                                                                                                                   | (empty)                                                                                       | v3.3.1+  |                | v5.0.0                |
| `API_PATH`                                                               | PATH in API endpoint URL at API docs page.                                                                                                                                                                                                                                                                                                                                                                                                        | /                                                                                             | v3.1.0+  | ✅              | v5.1.1                |
| `SOCKET_ROOT`                                                            | Custom websocket path.                                                                                                                                                                                                                                                                                                                                                                                                                            | (empty)                                                                                       | v3.0.0+  | ✅              | v5.1.1                |
| `MAX_SIZE_UNLESS_HIDE_ARRAY`                                             | Hide long arrays in smart-contracts. To get more details: [#4218](https://github.com/blockscout/blockscout/pull/4218)                                                                                                                                                                                                                                                                                                                             | 50                                                                                            | v3.7.1+  |                | v5.1.2                |
| `ALLOWED_EVM_VERSIONS`                                                   | the comma-separated list of allowed EVM versions for contract verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964)                                                                                                                                                                                                                                                                                | "homestead, tangerineWhistle, spuriousDragon, byzantium, constantinople, petersburg,istanbul" | v2.0.0+  |                | v5.1.2                |
| `DISABLE_KNOWN_TOKENS`                                                   | Disables or enables token symbol for known contract.                                                                                                                                                                                                                                                                                                                                                                                              | false                                                                                         | v3.4.0+  |                | v5.1.2                |
| `TOKEN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD_MINUTES`                      | A threshold to invalidate token balance cache. Implemented in [#3870](https://github.com/blockscout/blockscout/pull/3870)                                                                                                                                                                                                                                                                                                                         | 60 minutes                                                                                    | v3.7.1+  |                | v5.1.2                |
| `COIN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD_MINUTES`                       | A threshold to invalidate coin balance cache. Implemented in [#5240](https://github.com/blockscout/blockscout/pull/5240)                                                                                                                                                                                                                                                                                                                          | 60 minutes                                                                                    | v4.1.2+  |                | v5.1.2                |
| `CUSTOM_CONTRACT_ADDRESSES_TEST_TOKEN`                                   | List of test tokens addresses: test label will be applied and those tokens will be excluded from omni bridge market cap calculation.                                                                                                                                                                                                                                                                                                              | (empty)                                                                                       | v3.6.0+  |                | v5.1.2                |
| `CACHE_TOKEN_EXCHANGE_RATE_PERIOD`                                       | Managing cache invalidation for token's exchange rate.                                                                                                                                                                                                                                                                                                                                                                                            | 1 hour                                                                                        | v3.5.0+  |                | v5.1.2                |
| `INDEXER_DISABLE_EMPTY_BLOCK_SANITIZER`                                  | Empty blocks sanitizer is disabled if `true`                                                                                                                                                                                                                                                                                                                                                                                                      | false                                                                                         | v4.1.3+  |                | v5.1.2                |
| `HISTORY_FETCH_INTERVAL`                                                 | Interval how often to request count of txs per current day in order to display txs count per day chart on the main page. [Time format](/setup/env-variables#time-format).                                                                                                                                                                                                                                                                         | 1h                                                                                            | v3.1.2+  |                | v5.1.3                |
| `WOBSERVER_ENABLED`                                                      | If `true` enables wobserver interface.                                                                                                                                                                                                                                                                                                                                                                                                            | (empty)                                                                                       | v3.3.2+  |                | v5.1.3                |
| `VISUALIZE_SOL2UML_ENABLED`                                              | If `true`, integration with [Rust sol2uml visualizer](https://github.com/blockscout/blockscout-rs/tree/main/visualizer) is enabled. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401)                                                                                                                                                                                                                                    | (empty)                                                                                       | v5.0.0+  |                | v5.1.3                |
| `VISUALIZE_SOL2UML_SERVICE_URL`                                          | URL of Rust visualizer. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401)                                                                                                                                                                                                                                                                                                                                                | (empty)                                                                                       | v5.0.0+  |                | v5.1.3                |
| `SIG_PROVIDER_SERVICE_URL`                                               | If `true`, integration with [Rust sig-provider service](https://github.com/blockscout/blockscout-rs/tree/main/sig-provider) is enabled. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                                                                                                                                                | (empty)                                                                                       | v5.1.0+  |                | v5.1.3                |
| `SIG_PROVIDER_ENABLED`                                                   | URL of Rust sig-provider service. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                                                                                                                                                                                                                                                      | (empty)                                                                                       | v5.1.0+  |                | v5.1.3                |
| `ENABLE_RUST_VERIFICATION_SERVICE`                                       | If `true`, integration with [Rust smart-contract verifier](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier) is enabled. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860)                                                                                                                                                                                                                  | (empty)                                                                                       | v4.1.8+  |                | v5.1.3                |
| `RUST_VERIFICATION_SERVICE_URL`                                          | URL of Rust smart-contract verifier. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860)                                                                                                                                                                                                                                                                                                                                   | (empty)                                                                                       | v4.1.8+  |                | v5.1.3                |
| `LINK_TO_OTHER_EXPLORERS`                                                | true/false. If true, links to other explorers are added in the footer.                                                                                                                                                                                                                                                                                                                                                                            | (empty)                                                                                       | v1.3.0+  |                | v5.1.3                |
| `OTHER_EXPLORERS`                                                        | The list of alternative explorers. This env var was introduced in PR [#3414](https://github.com/poanetwork/blockscout/pull/3414).                                                                                                                                                                                                                                                                                                                 | (empty)                                                                                       | v3.4.0+  |                | v5.1.3                |
| `FOOTER_ENABLE_FORUM_LINK`                                               | Enable forum menu item in the footer. Implemented in [#6351](https://github.com/blockscout/blockscout/pull/6351)                                                                                                                                                                                                                                                                                                                                  | false                                                                                         | v5.0.0+  |                | v5.1.3                |
| `ENABLE_SOURCIFY_INTEGRATION`                                            | Enables or disables verification of contracts through Sourcify.                                                                                                                                                                                                                                                                                                                                                                                   | false                                                                                         | v3.7.0+  |                | v5.1.3                |
| `ENABLE_TXS_STATS`                                                       | Disables or enables txs per day stats gathering.                                                                                                                                                                                                                                                                                                                                                                                                  | true                                                                                          | v3.1.2+  |                | v5.1.3                |
| `CACHE_ENABLE_TOTAL_GAS_USAGE_COUNTER`                                   | if `true`, enables cache for total gas usage counter.                                                                                                                                                                                                                                                                                                                                                                                             | `false`                                                                                       | v5.1.2+  |                | v5.1.3                |
| `LOGO_FOOTER`                                                            | Environment variable for the footer logo image location. The logo files names for different chains can be found [here](https://github.com/poanetwork/blockscout/tree/master/apps/block_scout_web/assets/static/images).                                                                                                                                                                                                                           | /images/blockscout\_logo.svg                                                                  |          |                | v5.1.3                |
| `INDEXER_TOKEN_INSTANCE_CONCURRENCY`                                     | Concurrency for token instance fetcher. Implemented in [#6981](https://github.com/blockscout/blockscout/pull/6981).                                                                                                                                                                                                                                                                                                                               | 10                                                                                            | v5.1.2+  |                | v5.1.4                |
| `INDEXER_TOKEN_INSTANCE_BATCH_SIZE`                                      | Batch size for token instance fetcher. Implemented in [#6981](https://github.com/blockscout/blockscout/pull/6981).                                                                                                                                                                                                                                                                                                                                | 1                                                                                             | v5.1.2+  |                | v5.1.4                |
| `DISABLE_TOKEN_INSTANCE_FETCHER`                                         | If `true`, token instance fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                     | `false`                                                                                       | v5.0.0+  |                | v5.1.4                |
| `ACCOUNT_AUTH0_LOGOUT_URL`                                               | Auth0 logout URL [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                                                                                                                                                                                                                                                | (empty)                                                                                       | v5.0.0+  |                | v5.1.4                |
| `ACCOUNT_AUTH0_LOGOUT_RETURN_URL`                                        | Auth0 logout return URL [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                                                                                                                                                                                                                                         | (empty)                                                                                       | v5.0.0+  |                | v5.1.4                |
| `ACCOUNT_AUTHENTICATE_ENDPOINT_API_KEY`                                  | `api/account/v1/authenticate` api key ([#7068](https://github.com/blockscout/blockscout/pull/7068))                                                                                                                                                                                                                                                                                                                                               | (empty)                                                                                       | v5.1.2+  |                | v5.1.5                |
| `DISABLE_READ_API`                                                       | If `true`, read-only endpoints to API are hidden (compile-time).                                                                                                                                                                                                                                                                                                                                                                                  | `false`                                                                                       | v2.0.3+  | ✅              | v5.1.5                |
| `DISABLE_WRITE_API`                                                      | If `true`, write endpoints to API are hidden (compile-time).                                                                                                                                                                                                                                                                                                                                                                                      | `false`                                                                                       | v2.0.3+  | ✅              | v5.1.5                |
| `CONTRACT_VERIFICATION_ALLOWED_EVM_VERSIONS`                             | the comma-separated list of allowed EVM versions for contract verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964)                                                                                                                                                                                                                                                                                | "homestead, tangerineWhistle, spuriousDragon, byzantium, constantinople, petersburg,istanbul" | v2.0.0+  |                | v5.2.0                |
| `EXCHANGE_RATES_SOURCE`                                                  | This environment variable is used to calculate the exchange rates. Available value is `token_bridge`. Available values are also `coin_gecko` and `coin_market_cap`.                                                                                                                                                                                                                                                                               | (empty)                                                                                       | v4.1.4+  |                | v5.2.3                |
| `INDEXER_ZKEVM_BATCHES_ENABLED`                                          | Enables Polygon zkEVM batches fetcher. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                                                                                                                | `false`                                                                                       | v5.3.1+  |                | v6.2.0                |
| `INDEXER_ZKEVM_BATCHES_CHUNK_SIZE`                                       | The number of Polygon zkEVM batches in one chunk when reading them from RPC. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                                                                          | 20                                                                                            | v5.3.1+  |                | v6.2.0                |
| `INDEXER_ZKEVM_BATCHES_RECHECK_INTERVAL`                                 | The latest batch rechecking interval, seconds. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                                                                                                        | 60                                                                                            | v5.3.1+  |                | v6.2.0                |
| `GRAPHIQL_TRANSACTION`                                                   | Default transaction hash in a sample query to GraphiQL.                                                                                                                                                                                                                                                                                                                                                                                           | (empty)                                                                                       | v1.2.0+  | ✅              | v6.4.0                |
| `INDEXER_TOKEN_INSTANCE_RETRY_REFETCH_INTERVAL`                          | Interval between attempts to fetch token instance metadata. [Time format](/setup/env-variables#time-format). Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                          | `24h`                                                                                         | v5.1.4+  |                | v6.6.0                |
| `INDEXER_INTERNAL_TRANSACTIONS_INDEXING_FINISHED_THRESHOLD`              | In the case when the 1st tx in the chain already has internal transactions, If the number of blocks in pending\_block\_operations is less than the value in this env var, Blockscout will consider, that indexing of internal transactions finished, otherwise, it will consider, that indexing is still taking place and the indexing banner will appear at the top. Implemented in [#7576](https://github.com/blockscout/blockscout/pull/7576). | 1000                                                                                          | v5.2.0+  |                | v6.6.0                |
| `INDEXER_OPTIMISM_L1_DEPOSITS_START_BLOCK`                               | The number of the L1 block from which deposits will be fetched. Implemented in [#6993](https://github.com/blockscout/blockscout/pull/6993).                                                                                                                                                                                                                                                                                                       | (empty)                                                                                       | v6.3.0+  |                | v6.8.0                |
| `INDEXER_OPTIMISM_L1_WITHDRAWALS_START_BLOCK`                            | The number of start block on L1 to index withdrawal events. If the table of withdrawal events is not empty, the process will continue indexing from the last indexed withdrawal event. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                | (empty)                                                                                       | v6.3.0+  |                | v6.8.0                |
| `INDEXER_OPTIMISM_L1_OUTPUT_ROOTS_START_BLOCK`                           | The number of start block on L1 to index output roots. If the table of output roots is not empty, the process will continue indexing from the last indexed root. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                      | (empty)                                                                                       | v6.3.0+  |                | v6.8.0                |
| `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK`                                  | The number of start block on L1 to index transaction batches. If the table of batches is not empty, the process will continue indexing from the last indexed batch. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                   | (empty)                                                                                       | v6.3.0+  |                | v6.8.0                |
| `INDEXER_OPTIMISM_L1_DEPOSITS_BATCH_SIZE`                                | Number of blocks in a single `eth_getLogs` request of the Deposits fetcher. Implemented in [#6993](https://github.com/blockscout/blockscout/pull/6993).                                                                                                                                                                                                                                                                                           | 500                                                                                           | v6.3.0+  |                | v6.8.0                |
| `METRICS_DISABLE_PUBLIC`                                                 | Variable to disable running queries at /public-metrics endpoint. Implemented in [#10279](https://github.com/blockscout/blockscout/pull/10279).                                                                                                                                                                                                                                                                                                    | false                                                                                         | v6.7.2+  |                | v6.8.0                |
| `RESTRICTED_LIST`                                                        | A comma-separated list of addresses to enable restricted access to them.                                                                                                                                                                                                                                                                                                                                                                          | (empty)                                                                                       | v3.3.3+  |                | v6.10.0               |
| `RESTRICTED_LIST_KEY`                                                    | A key to access addresses listed in`RESTRICTED_LIST` variable. Can be passed via query param to the page's URL: `?key=...`                                                                                                                                                                                                                                                                                                                        | (empty)                                                                                       | v3.3.3+  |                | v6.10.0               |
| `CHECKSUM_FUNCTION`                                                      | Defines checksum address function. 2 available values: `rsk`, `eth`                                                                                                                                                                                                                                                                                                                                                                               | `eth`                                                                                         | v2.0.1+  |                | v7.0.0                |
| `TOKEN_ID_MIGRATION_FIRST_BLOCK`                                         | Bottom block for token id migration. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                                                                                   | 0                                                                                             | v5.0.0+  |                | v7.0.0                |
| `TOKEN_ID_MIGRATION_CONCURRENCY`                                         | Number of workers performing the token id migration. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                                                                   | 1                                                                                             | v5.0.0+  |                | v7.0.0                |
| `TOKEN_ID_MIGRATION_BATCH_SIZE`                                          | Interval of token transfer block numbers processed by a token id migration worker at a time. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                           | 500                                                                                           | v5.0.0+  |                | v7.0.0                |
| `SHRINK_INTERNAL_TRANSACTIONS_BATCH_SIZE`                                | Batch size of the shrink internal transactions migration. *Note*: before release "v6.8.0", the default value was 1000. Implemented in [#10567](https://github.com/blockscout/blockscout/pull/10567), changed default value in [#10689](https://github.com/blockscout/blockscout/pull/10689).                                                                                                                                                      | 100                                                                                           | v6.8.0+  |                | v7.0.0                |
| `SHRINK_INTERNAL_TRANSACTIONS_CONCURRENCY`                               | Concurrency of the shrink internal transactions migration. Implemented in [#10567](https://github.com/blockscout/blockscout/pull/10567).                                                                                                                                                                                                                                                                                                          | 10                                                                                            | v6.8.0+  |                | v7.0.0                |
| `TOKEN_INSTANCE_OWNER_MIGRATION_CONCURRENCY`                             | Concurrency of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                   | 5                                                                                             | v5.3.0+  |                | v7.0.0                |
| `TOKEN_INSTANCE_OWNER_MIGRATION_BATCH_SIZE`                              | Batch size of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                    | 50                                                                                            | v5.3.0+  |                | v7.0.0                |
| `TOKEN_INSTANCE_OWNER_MIGRATION_ENABLED`                                 | Enable of backfiller from [#8386](https://github.com/blockscout/blockscout/pull/8386) implemented in [#8752](https://github.com/blockscout/blockscout/pull/8752)                                                                                                                                                                                                                                                                                  | false                                                                                         | v5.3.2+  |                | v7.0.0                |
| `DENORMALIZATION_MIGRATION_BATCH_SIZE`                                   | Number of transactions to denormalize (add block timestamp and consensus) in the batch.                                                                                                                                                                                                                                                                                                                                                           | 500                                                                                           | v6.0.0+  |                | v7.0.0                |
| `DENORMALIZATION_MIGRATION_CONCURRENCY`                                  | Number of parallel denormalization transaction batches processing.                                                                                                                                                                                                                                                                                                                                                                                | 10                                                                                            | v6.0.0+  |                | v7.0.0                |
| `TOKEN_TRANSFER_TOKEN_TYPE_MIGRATION_BATCH_SIZE`                         | Number of token transfers to denormalize (add token\_type) in the batch.                                                                                                                                                                                                                                                                                                                                                                          | 100                                                                                           | v6.3.0+  |                | v7.0.0                |
| `TOKEN_TRANSFER_TOKEN_TYPE_MIGRATION_CONCURRENCY`                        | Number of parallel denormalization token transfer batches processing.                                                                                                                                                                                                                                                                                                                                                                             | 1                                                                                             | v6.3.0+  |                | v7.0.0                |
| `SANITIZE_INCORRECT_NFT_BATCH_SIZE`                                      | Number of token transfers to sanitize in the batch.                                                                                                                                                                                                                                                                                                                                                                                               | 100                                                                                           | v6.3.0+  |                | v7.0.0                |
| `SANITIZE_INCORRECT_NFT_CONCURRENCY`                                     | Number of parallel sanitizing token transfer batches processing.                                                                                                                                                                                                                                                                                                                                                                                  | 1                                                                                             | v6.3.0+  |                | v7.0.0                |
| `SANITIZE_INCORRECT_NFT_TIMEOUT`                                         | Timeout between sanitizing token transfer batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358)                                                                                                                                                                                                                                                                                                        | 0                                                                                             | v6.10.0+ |                | v7.0.0                |
| `SANITIZE_INCORRECT_WETH_BATCH_SIZE`                                     | Number of token transfers to sanitize in the batch. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134)                                                                                                                                                                                                                                                                                                                  | 100                                                                                           | v6.8.0+  |                | v7.0.0                |
| `SANITIZE_INCORRECT_WETH_CONCURRENCY`                                    | Number of parallel sanitizing token transfer batches processing. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134)                                                                                                                                                                                                                                                                                                     | 1                                                                                             | v6.8.0+  |                | v7.0.0                |
| `SANITIZE_INCORRECT_WETH_TIMEOUT`                                        | Timeout between sanitizing token transfer batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358)                                                                                                                                                                                                                                                                                                        | 0                                                                                             | v6.10.0+ |                | v7.0.0                |
| `REINDEX_INTERNAL_TRANSACTIONS_STATUS_BATCH_SIZE`                        | Number of internal transactions to reindex in the batch. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358)                                                                                                                                                                                                                                                                                                             | 100                                                                                           | v6.10.0+ |                | v7.0.0                |
| `REINDEX_INTERNAL_TRANSACTIONS_STATUS_CONCURRENCY`                       | Number of parallel reindexing internal transaction batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358)                                                                                                                                                                                                                                                                                               | 1                                                                                             | v6.10.0+ |                | v7.0.0                |
| `REINDEX_INTERNAL_TRANSACTIONS_STATUS_TIMEOUT`                           | Timeout between reindexing internal transaction batches processing. Implemented in [#11358](https://github.com/blockscout/blockscout/pull/11358)                                                                                                                                                                                                                                                                                                  | 0                                                                                             | v6.10.0+ |                | v7.0.0                |
| `FILECOIN_PENDING_ADDRESS_OPERATIONS_MIGRATION_BATCH_SIZE`               | Specifies the number of address records processed per batch during the backfill of pending address fetch operations. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                                                                                                                                                                | 100                                                                                           | v6.9.0+  |                | v7.0.0                |
| `FILECOIN_PENDING_ADDRESS_OPERATIONS_MIGRATION_CONCURRENCY`              | Specifies the number of concurrent processes used during the backfill of pending address fetch operations. Implemented in [#10468](https://github.com/blockscout/blockscout/pull/10468).                                                                                                                                                                                                                                                          | 1                                                                                             | v6.9.0+  |                | v7.0.0                |
| `ARBITRUM_DA_RECORDS_NORMALIZATION_MIGRATION_BATCH_SIZE`                 | Specifies the number of address records processed per batch during normalization of batch-to-blob associations by moving them from arbitrum\_da\_multi\_purpose to a dedicated arbitrum\_batches\_to\_da\_blobs table. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                              | 500                                                                                           | v6.10.1+ |                | v7.0.0                |
| `ARBITRUM_DA_RECORDS_NORMALIZATION_MIGRATION_CONCURRENCY`                | Specifies the number of concurrent processes used during normalization of batch-to-blob associations by moving them from arbitrum\_da\_multi\_purpose to a dedicated arbitrum\_batches\_to\_da\_blobs table. Implemented in [#11798](https://github.com/blockscout/blockscout/pull/11798).                                                                                                                                                        | 1                                                                                             | v6.10.1+ |                | v7.0.0                |
| `CACHE_ADDRESS_WITH_BALANCES_UPDATE_INTERVAL`                            | Interval to restart the task which calculates addresses with balances.                                                                                                                                                                                                                                                                                                                                                                            | 30m                                                                                           | v4.1.3+  |                | v8.0.0                |
| `HEALTHY_BLOCKS_PERIOD`                                                  | New blocks indexed max delay in /health API endpoint. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#2294](https://github.com/blockscout/blockscout/pull/2294/)                                                                                                                                                                                                                         | 5m                                                                                            | v2.0.2+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_LIMIT`                                        | Sets the maximum number of token prices returned in a single request. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550).                                                                                                                                                                                                                                                                                               | 1000                                                                                          | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_SOURCE`                                                  | Source for native coin and tokens price fetching. Possible values are: `coin_gecko`, `coin_market_cap` or `mobula`. Replaced with `MARKET_NATIVE_COIN_SOURCE`                                                                                                                                                                                                                                                                                     | `coin_gecko`                                                                                  | v4.1.4+  |                | v8.0.0                |
| `EXCHANGE_RATES_SECONDARY_COIN_SOURCE`                                   | Source for secondary coin fetching. Possible values are: `coin_gecko`, `coin_market_cap` or `mobula`. Replaced with `MARKET_SECONDARY_COIN_SOURCE`                                                                                                                                                                                                                                                                                                | `coin_gecko`                                                                                  | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_MARKET_CAP_SOURCE`                                       | Sets the source for market cap fetching. Available values `coin_gecko`, `mobula`, `coin_market_cap`, `cryptorank`. Replaced with `MARKET_MARKET_CAP_HISTORY_SOURCE`                                                                                                                                                                                                                                                                               | `coin_gecko`                                                                                  | v5.2.3+  |                | v8.0.0                |
| `EXCHANGE_RATES_TVL_SOURCE`                                              | Sets the source for TVL fetching. Available value is `defillama`. Replaced with `MARKET_TVL_HISTORY_SOURCE`                                                                                                                                                                                                                                                                                                                                       | (empty)                                                                                       | v5.3.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_PRICE_SOURCE`                                            | Sets the source for price fetching. Available values are `crypto_compare`, `coin_gecko`, `mobula`, `coin_market_cap` and `cryptorank`. Replaced with `MARKET_NATIVE_COIN_HISTORY_SOURCE`                                                                                                                                                                                                                                                          | `crypto_compare`                                                                              | v5.2.3+  |                | v8.0.0                |
| `EXCHANGE_RATES_MOBULA_COIN_ID`                                          | Explicitly set Mobula coin ID. Replaced with `MARKET_MOBULA_COIN_ID`                                                                                                                                                                                                                                                                                                                                                                              | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_MOBULA_SECONDARY_COIN_ID`                                | Explicitly set Mobula coin ID for secondary coin market chart. Replaced with `MARKET_MOBULA_SECONDARY_COIN_ID`                                                                                                                                                                                                                                                                                                                                    | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_MOBULA_API_KEY`                                          | Mobula API key. Replaced with `MARKET_MOBULA_API_KEY`                                                                                                                                                                                                                                                                                                                                                                                             | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_COIN_ID`                                       | Explicitly set CoinGecko coin ID. Replaced with `MARKET_COINGECKO_COIN_ID`                                                                                                                                                                                                                                                                                                                                                                        | (empty)                                                                                       | v4.1.4+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_SECONDARY_COIN_ID`                             | Explicitly set CoinGecko coin ID for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483). Replaced with `MARKET_COINGECKO_SECONDARY_COIN_ID`                                                                                                                                                                                                                                                  | (empty)                                                                                       | v6.3.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_API_KEY`                                       | CoinGecko API key. Replaced with `MARKET_COINGECKO_API_KEY`                                                                                                                                                                                                                                                                                                                                                                                       | (empty)                                                                                       | v4.1.4+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_BASE_URL`                                      | If set, overrides the Coingecko base URL. Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679). Replaced with `MARKET_COINGECKO_BASE_URL`                                                                                                                                                                                                                                                                                   | (empty)                                                                                       | v6.4.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_BASE_PRO_URL`                                  | If set, overrides the Coingecko Pro base URL. Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679). Replaced with `MARKET_COINGECKO_BASE_PRO_URL`                                                                                                                                                                                                                                                                           | (empty)                                                                                       | v6.4.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINMARKETCAP_API_KEY`                                   | CoinMarketCap API key. Required, if `EXCHANGE_RATES_MARKET_CAP_SOURCE`, `EXCHANGE_RATES_PRICE_SOURCE` is set to `coin_market_cap`. Replaced with `MARKET_COINMARKETCAP_API_KEY`                                                                                                                                                                                                                                                                   | (empty)                                                                                       | v4.1.4+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINMARKETCAP_COIN_ID`                                   | CoinMarketCap coin id. Replaced with `MARKET_COINMARKETCAP_COIN_ID`                                                                                                                                                                                                                                                                                                                                                                               | (empty)                                                                                       | v5.2.1+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINMARKETCAP_SECONDARY_COIN_ID`                         | CoinMarketCap coin id for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483). Replaced with `MARKET_COINMARKETCAP_SECONDARY_COIN_ID`                                                                                                                                                                                                                                                         | (empty)                                                                                       | v6.3.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINMARKETCAP_BASE_URL`                                  | If set, overrides the CoinMarketCap base URL (Free and Pro). Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679). Replaced with `MARKET_COINMARKETCAP_BASE_URL`                                                                                                                                                                                                                                                            | (empty)                                                                                       | v6.4.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_DEFILLAMA_COIN_ID`                                       | DefiLlama coin id. Replaced with `MARKET_DEFILLAMA_COIN_ID`                                                                                                                                                                                                                                                                                                                                                                                       | (empty)                                                                                       | v5.3.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_FETCH_BTC_VALUE`                                         | if `true` explorer application will fetch btc\_value for token exchange rates. Implemented in [#5671](https://github.com/blockscout/blockscout/pull/5671). Replaced with `MARKET_FETCH_BTC_VALUE`                                                                                                                                                                                                                                                 | (empty)                                                                                       | v4.1.5+  |                | v8.0.0                |
| `EXCHANGE_RATES_COINGECKO_PLATFORM_ID`                                   | [CoinGecko](https://www.coingecko.com/) platform id for which token prices are fetched, see full list in [`/asset_platforms`](https://api.coingecko.com/api/v3/asset_platforms) endpoint. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). Replaced with `MARKET_COINGECKO_PLATFORM_ID`                                                                                                                                | `ethereum`                                                                                    | v5.1.2+  |                | v8.0.0                |
| `TOKEN_EXCHANGE_RATE_INTERVAL`                                           | Interval between batch requests of token prices. Can be decreased in order to fetch prices faster if you have pro rate limit. [Time format](https://github.com/blockscout/docs/blob/master/setup/env-variables/deprecated-env-variables/backend-env-variables.md#time-format). Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). Replaced with `MARKET_TOKENS_INTERVAL`                                                 | `5s`                                                                                          | v5.1.2+  |                | v8.0.0                |
| `TOKEN_EXCHANGE_RATE_REFETCH_INTERVAL`                                   | Interval between refetching token prices, responsible for the relevance of prices. [Time format](https://github.com/blockscout/docs/blob/master/setup/env-variables/deprecated-env-variables/backend-env-variables.md#time-format). Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). Replaced with `MARKET_TOKENS_REFETCH_INTERVAL`                                                                                    | `1 hour`                                                                                      | v5.1.2+  |                | v8.0.0                |
| `TOKEN_EXCHANGE_RATE_MAX_BATCH_SIZE`                                     | Batch size of a single token price request. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). Replaced with `MARKET_TOKENS_MAX_BATCH_SIZE`                                                                                                                                                                                                                                                                              | `150`                                                                                         | v5.1.2+  |                | v8.0.0                |
| `DISABLE_TOKEN_EXCHANGE_RATE`                                            | If `true` disables fetching of token price. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). Replaced with `MARKET_TOKENS_FETCHER_ENABLED` (with inverted default)                                                                                                                                                                                                                                                     | `true`                                                                                        | v5.1.2+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTOCOMPARE_SECONDARY_COIN_SYMBOL`                     | CryptoCompare coin symbol for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483). Replaced with `MARKET_CRYPTOCOMPARE_SECONDARY_COIN_SYMBOL`                                                                                                                                                                                                                                                 | (empty)                                                                                       | v6.3.0+  |                | v8.0.0                |
| `TOKEN_EXCHANGE_RATES_SOURCE`                                            | Sets the source for tokens price fetching. Available values are `coin_gecko`, `cryptorank`. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_TOKENS_SOURCE`                                                                                                                                                                                                                                    | `coin_gecko`                                                                                  | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_SECONDARY_COIN_ID`                            | Sets Cryptorank coin ID for secondary coin market chart. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_CRYPTORANK_SECONDARY_COIN_ID`                                                                                                                                                                                                                                                        | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_PLATFORM_ID`                                  | Sets Cryptorank platform ID. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_CRYPTORANK_PLATFORM_ID`                                                                                                                                                                                                                                                                                          | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_BASE_URL`                                     | If set, overrides the Cryptorank API url. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_CRYPTORANK_BASE_URL`                                                                                                                                                                                                                                                                                | `https://api.cryptorank.io/v1/`                                                               | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_API_KEY`                                      | Cryptorank API key. Current implementation uses dedicated beta Cryptorank API endpoint. If you want to integrate Cryptorank price fetching you should contact Cryptorank to receive an API key. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_CRYPTORANK_API_KEY`                                                                                                                           | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `EXCHANGE_RATES_CRYPTORANK_COIN_ID`                                      | Sets Cryptorank coin ID. Implemented in [#10550](https://github.com/blockscout/blockscout/pull/10550). Replaced with `MARKET_CRYPTORANK_COIN_ID`                                                                                                                                                                                                                                                                                                  | (empty)                                                                                       | v6.8.0+  |                | v8.0.0                |
| `CACHE_EXCHANGE_RATES_PERIOD`                                            | Value to tune the time to live of exchange rates. [Time format](https://github.com/blockscout/docs/blob/master/setup/env-variables/deprecated-env-variables/backend-env-variables.md#time-format). Implemented in [#5671](https://github.com/blockscout/blockscout/pull/5671).                                                                                                                                                                    | `10m`                                                                                         | v4.1.5+  |                | v8.0.0                |
| `DISABLE_EXCHANGE_RATES`                                                 | Disables or enables fetching of coin price from Coingecko API. Replaced with `DISABLE_MARKET`                                                                                                                                                                                                                                                                                                                                                     | `false`                                                                                       | v3.1.2+  |                | v8.0.0                |
| `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_RETRY_FETCHER`              | If `true`, `retry` multichain search export fetcher doesn't run. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). Replaced with `INDEXER_DISABLE_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_PROCESSOR_FETCHER`.                                                                                                                                                                                                          | `false`                                                                                       | v8.1.0+  |                | v9.0.0                |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_RETRY_BATCH_SIZE`                   | Batch size for `retry` multichain search export fetcher. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). Replaced with `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_PROCESSOR_BATCH_SIZE`.                                                                                                                                                                                                                       | 10                                                                                            | v8.1.0+  |                | v9.0.0                |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_RETRY_CONCURRENCY`                  | Concurrency for `retry` multichain search export fetcher. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). Replaced with `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_PROCESSOR_CONCURRENCY`.                                                                                                                                                                                                                     | 10                                                                                            | v8.1.0+  |                | v9.0.0                |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_RETRY_ENQUEUE_BUSY_WAITING_TIMEOUT` | Timeout before new attempt to append item to `retry` multichain search export queue if it's full. [Time format](backend-env-variables.md#time-format). Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). Replaced with `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_PROCESSOR_ENQUEUE_BUSY_WAITING_TIMEOUT`.                                                                                                       | 1s                                                                                            | v8.1.0+  |                | v9.0.0                |
| `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_RETRY_MAX_QUEUE_SIZE`               | Maximum size of `retry` multichain search export queue. Implemented in [#12377](https://github.com/blockscout/blockscout/pull/12377). Replaced with `INDEXER_MULTICHAIN_SEARCH_DB_EXPORT_MAIN_QUEUE_PROCESSOR_MAX_QUEUE_SIZE`.                                                                                                                                                                                                                    | 1000                                                                                          | v8.1.0+  |                | v9.0.0                |
| `API_RATE_LIMIT_TIME_INTERVAL`                                           | Time interval of rate limit. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148). Replaced with `API_RATE_LIMIT_BY_KEY_TIME_INTERVAL`, `API_RATE_LIMIT_BY_WHITELISTED_IP_TIME_INTERVAL`, `API_RATE_LIMIT_UI_V2_WITH_TOKEN_TIME_INTERVAL`, `API_RATE_LIMIT_BY_ACCOUNT_API_KEY_TIME_INTERVAL`, `API_RATE_LIMIT_BY_IP_TIME_INTERVAL`                                                                                          | `1s`                                                                                          | v5.1.3+  |                | v9.0.0                |
| `API_RATE_LIMIT_UI_V2_TOKEN_TTL_IN_SECONDS`                              | TTL for token issued after submitting correct CAPTCHA for an API v2 requests from UI. In seconds. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                                                                                                                                                                      |                                                                                               | v5.1.3+  |                | v9.0.0                |
| `INDEXER_POLYGON_EDGE_L1_RPC`                                            | The RPC endpoint for L1 used to fetch deposit or withdrawal events. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                                                                                   |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L1_EXIT_HELPER_CONTRACT`                           | The address of ExitHelper contract on L1 (root chain) used to fetch withdrawal exits. Required for withdrawal events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                        |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L1_WITHDRAWALS_START_BLOCK`                        | The number of start block on L1 (root chain) to index withdrawal exits. If the table of withdrawal exits is not empty, the process will continue indexing from the last indexed message. If empty or not defined, the withdrawal exits are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                               |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L1_STATE_SENDER_CONTRACT`                          | The address of StateSender contract on L1 (root chain) used to fetch deposits. Required for deposit events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                                  |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L1_DEPOSITS_START_BLOCK`                           | The number of start block on L1 (root chain) to index deposits. If the table of deposits is not empty, the process will continue indexing from the last indexed message. If empty or not defined, the deposits are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                       |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L2_STATE_SENDER_CONTRACT`                          | The address of L2StateSender contract on L2 (child chain) used to fetch withdrawals. Required for withdrawal events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                         |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L2_WITHDRAWALS_START_BLOCK`                        | The number of start block on L2 (child chain) to index withdrawals. If the table of withdrawals is not empty, the process will fill gaps and then continue indexing from the last indexed message. If empty or not defined, the withdrawals are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                          |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L2_STATE_RECEIVER_CONTRACT`                        | The address of StateReceiver contract on L2 (child chain) used to fetch deposit executes. Required for deposit events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                       |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_L2_DEPOSITS_START_BLOCK`                           | The number of start block on L2 (child chain) to index deposit executes. If the table of deposit executes is not empty, the process will fill gaps and then continue indexing from the last indexed message. If empty or not defined, the deposit executes are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                           |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `INDEXER_POLYGON_EDGE_ETH_GET_LOGS_RANGE_SIZE`                           | Block range size for eth\_getLogs request in Polygon Edge indexer modules. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                                                                                                            |                                                                                               | v5.3.0+  |                | v9.1.0                |
| `ACCOUNT_PUBLIC_TAGS_AIRTABLE_URL`                                       | Airtable URL for public tag requests functionality                                                                                                                                                                                                                                                                                                                                                                                                |                                                                                               | v5.0.0+  |                | v9.1.0                |
| `ACCOUNT_PUBLIC_TAGS_AIRTABLE_API_KEY`                                   | Airtable API key for public tag requests functionality                                                                                                                                                                                                                                                                                                                                                                                            |                                                                                               | v5.0.0+  |                | v9.1.0                |
| `NFT_MEDIA_HANDLER_NODES_MAP`                                            | String in json map format, where key is erlang node and value is folder in R2/S3 bucket, example: `"{\"producer@172.18.0.4\": \"/folder_1\"}"`. If nft\_media\_handler runs in one pod with indexer, map should contain `self` key                                                                                                                                                                                                                |                                                                                               | v6.10.0+ |                | v9.2.0                |
| `API_RATE_LIMIT`                                                         | A global API rate limit: number or requests per second for all users. Implemented in [#5030](https://github.com/blockscout/blockscout/pull/5030)                                                                                                                                                                                                                                                                                                  |                                                                                               | v4.1.1+  |                | v9.0.0                |
| `CACHE_PBO_COUNT_PERIOD`                                                 | Time interval to restart the task which calculates the total pending\_block\_operations count.                                                                                                                                                                                                                                                                                                                                                    | `20m`                                                                                         | v5.2.0+  |                | v10.0.0               |


# Previous ENV Variable Home Page
Source: https://docs.blockscout.com/setup/env-variables/deprecated-env-variables/env-variables

Previous home page for archival purposes.

<Warning>
  This page is kept for archival purposes. Please See [ENV variables](/setup/env-variables) and associated pages for updated info.
</Warning>

## Previous ENV Page

<Warning>
  The following are **backend variables only.**

  [Frontend ENVs are available here](/setup/env-variables/frontend-common-envs).
</Warning>

<Info>
  You will find deprecated ENV vars on the [Deprecated ENV Variables](https://docs.blockscout.com/for-developers/information-and-settings/deprecated-env-variables) page.
</Info>

### Set ENV Variables with CLI

Use the export command to set variables. For example:

```javascript theme={null}
$ export ETHEREUM_JSONRPC_VARIANT=nethermind
$ export COIN=POA
$ export NETWORK=POA
```

### Example ENV Variables Set

The following variables are set for the [Gnosis Chain Blockscout Instance](https://gnosis.blockscout.com/). *Note that some variables are not included as they contain private information which should not be exposed.*

<Card title="Gnosis-Chain-Variables.txt" icon="file-arrow-down" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2Fgit-blob-6ca29409491d82049d08c1b49886487cc8960e65%2FGnosis-Chain-Variables.txt?alt=media">
  6KB
</Card>

### Full ENV Variables CSV file

Last updated 4 August, 2023.

<Card title="Blockscout-ENV-variables.csv" icon="file-arrow-down" href="https://1077666658-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Lq1XoWGmy8zggj_u2fM%2Fuploads%2Fgit-blob-b21dd783ca3207e8fb1c078a4254e13a47b076c2%2FBlockscout-ENV-variables.csv?alt=media">
  50KB
</Card>

### Time format

Can be set in format `1h` for 1 hour, `1m` for 1 minute, `1s` or `1` for 1 second, `1ms` for 1 millisecond

<Warning>
  *Note*: Before release 5.1.2, all environment variables of time format supported only integers in seconds (without dimensions) as values.
</Warning>

### Available ENV Variables

<Info>
  This table is horizontally scrollable, version information is located in the last column. ENVs are listed by category:

  * [General](/setup/env-variables/deprecated-env-variables/env-variables#general)

  * [Indexer](/setup/env-variables/deprecated-env-variables/env-variables#indexer-management)

  * [Sanitizer](/setup/env-variables/deprecated-env-variables/env-variables#sanitizers-management)

  * [Polygon Edge](/setup/env-variables/deprecated-env-variables/env-variables#polygon-edge-management)

  * [Rootstock](/setup/env-variables/deprecated-env-variables/env-variables#rootstock-management)

  * [Shibarium](/setup/env-variables/deprecated-env-variables/env-variables#shibarium-management)

  * [Polygon zkEVM Rollup](/setup/env-variables/deprecated-env-variables/env-variables#polygon-zkevm-rollup-management)

  * [Optimism Rollup](/setup/env-variables/deprecated-env-variables/env-variables#optimism-rollup-management)

  * [zkSync Rollup](/setup/env-variables/deprecated-env-variables/env-variables#zksync-rollup-management)

  * [Arbitrum Rollup](/setup/env-variables/deprecated-env-variables/env-variables#arbitrum-rollup-management)

  * [Exchange Rates](/setup/env-variables/deprecated-env-variables/env-variables#exchange-rates-management)

  * [Cache](/setup/env-variables/deprecated-env-variables/env-variables#cache-management)

  * [Gas Price Oracle](/setup/env-variables/deprecated-env-variables/env-variables#gas-price-oracle-management)

  * [Main Page Dashboard](/setup/env-variables/deprecated-env-variables/env-variables#main-page-dashboard-management)

  * [Header](/setup/env-variables/deprecated-env-variables/env-variables#header-management)

  * [Footer](/setup/env-variables/deprecated-env-variables/env-variables#footer-management)

  * [Contract](/setup/env-variables/deprecated-env-variables/env-variables#contract-management)

  * [Bridged Tokens](/setup/env-variables/deprecated-env-variables/env-variables#bridged-tokens)

  * [Miscellaneous UI](/setup/env-variables/deprecated-env-variables/env-variables#misc-ui-management)

  * [CSV Export](/setup/env-variables/deprecated-env-variables/env-variables#csv-export)

  * [API Rate Limit](/setup/env-variables/deprecated-env-variables/env-variables#api-rate-limit-management)

  * [GraphQL API](/setup/env-variables/deprecated-env-variables/env-variables#graphql-api-management)

  * [Specific Smart Contracts](/setup/env-variables/deprecated-env-variables/env-variables#specific-smart-contracts)

  * [My Account](/setup/env-variables/deprecated-env-variables/env-variables#account-related-env-variables)

  * [Integrations](/setup/env-variables/deprecated-env-variables/env-variables#integrations)
</Info>

### General

| Variable                                                | Required | Description                                                                                                                                                                                                                                                                                                                                                                                                                                       | Default                                                                            | Version | Need recompile | Applications |
| ------------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------- | ------- | -------------- | ------------ |
| `DATABASE_URL`                                          | ✅        | Variable to define the Postgres Database endpoint.                                                                                                                                                                                                                                                                                                                                                                                                | (empty)                                                                            | all     |                | API, Indexer |
| `TEST_DATABASE_URL`                                     |          | Variable to define the endpoint of the Postgres Database that is used during testing. Implemented in [#9662](https://github.com/blockscout/blockscout/pull/9662).                                                                                                                                                                                                                                                                                 | (empty)                                                                            | v6.6.0+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_VARIANT`                              | ✅        | Tells the application which RPC Client the node is using (i.e. `erigon`, `geth`, `nethermind`, `besu`, `filecoin`, or `anvil`) ([See Client Settings for more info](/setup/requirements/client-settings))                                                                                                                                                                                                                                         | anvil                                                                              | all     |                | API, Indexer |
| `ETHEREUM_JSONRPC_HTTP_URL`                             | ✅        | The RPC endpoint used to fetch blocks, transactions, receipts, tokens.                                                                                                                                                                                                                                                                                                                                                                            | localhost:8545                                                                     | all     |                | API, Indexer |
| `DATABASE_READ_ONLY_API_URL`                            | ✅        | Variable to define the Postgres Database read-only replica endpoint. If it is provided, most of the read queries from API v2 and UI would go through this endpoint.                                                                                                                                                                                                                                                                               | (empty)                                                                            | all     |                | API          |
| `TEST_DATABASE_READ_ONLY_API_URL`                       |          | Variable to define the endpoint of the Postgres Database read-only replica that is used during testing. If it is provided, most of the read queries from API v2 and UI would go through this endpoint. Implemented in [#9662](https://github.com/blockscout/blockscout/pull/9662).                                                                                                                                                                | (empty)                                                                            | v6.6.0+ |                | API          |
| `DATABASE_QUEUE_TARGET`                                 |          | Management of [DB queue target](https://hexdocs.pm/db_connection/DBConnection.html#start_link/2-queue-config). Implemented in [#8991](https://github.com/blockscout/blockscout/pull/8991).                                                                                                                                                                                                                                                        | 50ms                                                                               | v5.4.0+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_TRACE_URL`                            |          | The RPC endpoint specifically for the Erigon/Geth/Nethermind/Besu client used by trace\_block and trace\_replayTransaction. This can be used to designate a tracing node.                                                                                                                                                                                                                                                                         | localhost:8545                                                                     | all     |                | API, Indexer |
| `ETHEREUM_JSONRPC_WS_URL`                               |          | The WebSockets RPC endpoint used to subscribe to the `newHeads` subscription alerting the indexer to fetch new blocks.                                                                                                                                                                                                                                                                                                                            | ws\://localhost:8546                                                               | all     |                | Indexer      |
| `ETHEREUM_JSONRPC_TRANSPORT`                            |          | Specifies the transport for Blockscout to connect to the Ethereum Node. Available transports are `http` and `ipc`. If `ipc` is selected, also set `IPC_PATH` variable.                                                                                                                                                                                                                                                                            | http                                                                               | v3.1.0+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_HTTP_INSECURE`                        |          | If `true` is set, allows insecure HTTP connections to the archive node. For instance, it allows to bypass expired SSL certificate at the archive node endpoint. Implemented in [#6573](https://github.com/blockscout/blockscout/pull/6573)                                                                                                                                                                                                        | (empty)                                                                            | v5.0.0+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_HTTP_TIMEOUT`                         |          | Timeout for ethereum json rpc http requests in seconds. Implemented in [#7089](https://github.com/blockscout/blockscout/pull/7089)                                                                                                                                                                                                                                                                                                                | 60                                                                                 | v5.1.2+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_USER`                                 |          | User in basic auth for JSON RPC endpoint. Implemented in [#6897](https://github.com/blockscout/blockscout/pull/6897)                                                                                                                                                                                                                                                                                                                              | (empty)                                                                            | v5.1.2+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_PASSWORD`                             |          | Password in basic auth for JSON RPC endpoint. Implemented in [#6897](https://github.com/blockscout/blockscout/pull/6897)                                                                                                                                                                                                                                                                                                                          | (empty)                                                                            | v5.1.2+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_HTTP_HEADERS`                         |          | Custom headers for JSON RPC endpoint in form of json object, example: `{"x-api-key": "nbvkhadvnbkdfav", "x-id": "ndjkfvndfkjv"}`. Implemented in [#7898](https://github.com/blockscout/blockscout/pull/7898)                                                                                                                                                                                                                                      | (empty)                                                                            | v5.2.1+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_FALLBACK_HTTP_URL`                    |          | Fallback JSON RPC HTTP url. Implemented in [#7246](https://github.com/blockscout/blockscout/pull/7246)                                                                                                                                                                                                                                                                                                                                            | (empty)                                                                            | v5.1.4+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_FALLBACK_TRACE_URL`                   |          | Fallback JSON RPC trace url. Implemented in [#7246](https://github.com/blockscout/blockscout/pull/7246)                                                                                                                                                                                                                                                                                                                                           | (empty)                                                                            | v5.1.4+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_FALLBACK_ETH_CALL_URL`                |          | Fallback JSON RPC `eth_call` url. Implemented in [#9511](https://github.com/blockscout/blockscout/pull/9511)                                                                                                                                                                                                                                                                                                                                      | (empty)                                                                            | v6.3.0+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_WAIT_PER_TIMEOUT`                     |          | Wait time for each recent timeout from node. Implemented in [#8292](https://github.com/blockscout/blockscout/pull/8292)                                                                                                                                                                                                                                                                                                                           | 20s                                                                                | v5.2.3+ |                | API, Indexer |
| `ETHEREUM_JSONRPC_ETH_CALL_URL`                         |          | JSON RPC url for eth\_call method. Implemented in [#9112](https://github.com/blockscout/blockscout/pull/9112)                                                                                                                                                                                                                                                                                                                                     | (empty)                                                                            | v6.0.0+ |                | API, Indexer |
| `NETWORK`                                               |          | Environment variable for the main EVM network such as Ethereum or POA.                                                                                                                                                                                                                                                                                                                                                                            | POA                                                                                | all     |                | API          |
| `SUBNETWORK`                                            |          | Environment variable for the subnetwork such as Core or Sokol Network. This will be displayed as selected in the chains list dropdown.                                                                                                                                                                                                                                                                                                            | POA Sokol                                                                          | all     |                | API          |
| `IPC_PATH`                                              |          | Path to the IPC file of the running node if IPC transport is chosen.                                                                                                                                                                                                                                                                                                                                                                              | (empty)                                                                            | v2.1.1+ |                | API, Indexer |
| `NETWORK_PATH`                                          |          | Used to set a network path other than what is displayed in the root directory. An example would be to add `/eth/mainnet/` to the root directory.                                                                                                                                                                                                                                                                                                  | /                                                                                  | all     |                | API          |
| `BLOCKSCOUT_HOST`                                       |          | Host for API endpoint examples.                                                                                                                                                                                                                                                                                                                                                                                                                   | localhost                                                                          | v2.1.0+ |                | API          |
| `BLOCKSCOUT_PROTOCOL`                                   |          | Url scheme for blockscout.                                                                                                                                                                                                                                                                                                                                                                                                                        | in prod env `https` is used, in dev env `http` is used                             | v2.1.0+ |                | API          |
| `SECRET_KEY_BASE`                                       | ✅        | The value is used to [sign cookies](https://hexdocs.pm/plug/Plug.Session.COOKIE.html). Use mix phx.gen.secret to generate a new Secret Key Base string to protect production assets.                                                                                                                                                                                                                                                              | (empty)                                                                            | all     |                | API          |
| `CHECK_ORIGIN`                                          |          | Used to check the origin of requests when the origin header is present. It defaults to `false`. In case of true, it will check against the host value.                                                                                                                                                                                                                                                                                            | false                                                                              | all     |                | API          |
| `PORT`                                                  |          | Default port the application runs on is 4000.                                                                                                                                                                                                                                                                                                                                                                                                     | 4000                                                                               | all     |                | API          |
| `COIN`                                                  |          | The coin here is checked via the CoinGecko API to obtain USD prices on graphs and other areas of the UI.                                                                                                                                                                                                                                                                                                                                          | POA                                                                                | all     |                | API, Indexer |
| `COIN_NAME`                                             |          | Displayed name of the coin. Also used for "Add chain to MetaMask" button and for Account functionality as native coin name in the email letters for watch list.                                                                                                                                                                                                                                                                                   | (empty)                                                                            | v4.1.2+ |                | API          |
| `EMISSION_FORMAT`                                       |          | Should be set to `POA` if you have block emission identical to POA Network. This env var is used only if `CHAIN_SPEC_PATH` is set.                                                                                                                                                                                                                                                                                                                | `DEFAULT`                                                                          | v2.0.4+ |                | API, Indexer |
| `CHAIN_SPEC_PATH`                                       |          | Chain specification path (absolute file system path or URL) to import block emission reward ranges and genesis account balances from. Geth- and OpenEthereum-style specs are supported.                                                                                                                                                                                                                                                           | (empty)                                                                            | v2.0.4+ |                | API, Indexer |
| `PRECOMPILED_CONTRACTS_CONFIG_PATH`                     |          | Precompiled contracts description path (absolute file system path or URL) to import ABI and source code of the precompiled contracts.                                                                                                                                                                                                                                                                                                             | (empty) or `/app/config/assets/precompiles-arbitrum.json` for `arbitrum` chaintype | v6.5.0+ |                | API, Indexer |
| `SUPPLY_MODULE`                                         |          | This environment variable is used by the RSK in order to tell the application how to calculate the total supply of the chain. Available values is `RSK`                                                                                                                                                                                                                                                                                           | (empty)                                                                            | all     |                | API, Indexer |
| `POOL_SIZE`                                             |          | Variable to define the number of database connections allowed excluding read-only API endpoints requests.                                                                                                                                                                                                                                                                                                                                         | 50                                                                                 | all     |                | API, Indexer |
| `POOL_SIZE_API`                                         |          | Variable to define the number of database connections allowed for read-only API endpoints requests.                                                                                                                                                                                                                                                                                                                                               | 50                                                                                 | v4.1.0+ |                | API          |
| `ECTO_USE_SSL`                                          |          | Production environment variable to use SSL on Ecto queries.                                                                                                                                                                                                                                                                                                                                                                                       | true                                                                               | all     |                | API, Indexer |
| `HEART_BEAT_TIMEOUT`                                    |          | Production environment variable to restart the application in the event of a crash.                                                                                                                                                                                                                                                                                                                                                               | 30                                                                                 | all     |                | API, Indexer |
| `HEART_COMMAND`                                         |          | Production environment variable to restart the application in the event of a crash.                                                                                                                                                                                                                                                                                                                                                               | (empty)                                                                            | all     |                | API, Indexer |
| `ELIXIR_VERSION`                                        |          | Elixir version to install on the node before Blockscout deploy. It is used in bash script in Terraform / Ansible deployment script                                                                                                                                                                                                                                                                                                                | (empty)                                                                            | all     |                | API, Indexer |
| `DISABLE_WEBAPP`                                        |          | If `true`, endpoints to webapp are hidden (compile-time). Also, enabling it makes notifications go through `db_notify`                                                                                                                                                                                                                                                                                                                            | `false`                                                                            | v2.0.3+ | ✅              | API, Indexer |
| `API_V1_READ_METHODS_DISABLED`                          |          | If `true`, read-only endpoints to API v1 are hidden (compile-time).                                                                                                                                                                                                                                                                                                                                                                               | `false`                                                                            | v5.1.5+ | ✅              | API          |
| `API_V1_WRITE_METHODS_DISABLED`                         |          | If `true`, write endpoints to API v1 are hidden (compile-time).                                                                                                                                                                                                                                                                                                                                                                                   | `false`                                                                            | v5.1.5+ | ✅              | API          |
| `DISABLE_API`                                           |          | If `true`, endpoint is not started. Set this if you want to use an indexer-only setup. Implemented in [#10032](https://github.com/blockscout/blockscout/pull/10032)                                                                                                                                                                                                                                                                               | `false`                                                                            | v6.6.0+ |                | API, Indexer |
| `WEBAPP_URL`                                            |          | Link to web application instance, e.g. `protocol://host/path`                                                                                                                                                                                                                                                                                                                                                                                     | (empty)                                                                            | v2.0.3+ |                | API          |
| `API_URL`                                               |          | Link to API instance, e.g. `protocol://host/path`                                                                                                                                                                                                                                                                                                                                                                                                 | (empty)                                                                            | v2.0.3+ |                | API          |
| `API_V2_ENABLED`                                        |          | Enable API V2. Implemented in [#6361](https://github.com/blockscout/blockscout/pull/6361) (v5.0.0+), default `true` since [#8802](https://github.com/blockscout/blockscout/pull/8802)                                                                                                                                                                                                                                                             | `true`                                                                             | v5.3.2+ |                | API          |
| `API_SENSITIVE_ENDPOINTS_KEY`                           |          | API key to protect some sensitive endpoints. Implemented in [#7355](https://github.com/blockscout/blockscout/pull/7355)                                                                                                                                                                                                                                                                                                                           | (empty)                                                                            | v5.1.5+ |                | API          |
| `CHECKSUM_ADDRESS_HASHES`                               |          | If set to `true`, redirects to checksummed version of address hashes.                                                                                                                                                                                                                                                                                                                                                                             | true                                                                               | v3.1.0+ |                | API          |
| `RESTRICTED_LIST`                                       |          | A comma-separated list of addresses to enable restricted access to them.                                                                                                                                                                                                                                                                                                                                                                          | (empty)                                                                            | v3.3.3+ |                | API          |
| `RESTRICTED_LIST_KEY`                                   |          | A key to access addresses listed in`RESTRICTED_LIST` variable. Can be passed via query param to the page's URL: `?key=...`                                                                                                                                                                                                                                                                                                                        | (empty)                                                                            | v3.3.3+ |                | API          |
| `CHAIN_TYPE`                                            |          | Specifies the model of data, enables fetchers, specific to the chain. Available values are `ethereum`, `optimism`, `arbitrum`, `polygon_zkevm`, `polygon_edge`, `rsk`, `shibarium`, `stability`, `suave`, `zetachain`, `filecoin`, `default`.                                                                                                                                                                                                     | `default`                                                                          | v5.3.0+ | ✅              | API, Indexer |
| `CHAIN_ID`                                              |          | Chain ID of the network. For instance, 100 in the case of xDai chain.                                                                                                                                                                                                                                                                                                                                                                             | (empty)                                                                            | v3.7.0+ |                | API, Indexer |
| `JSON_RPC`                                              |          | JSON RPC endpoint of the chain for the WalletConnect integration. Implemented in [#4931](https://github.com/blockscout/blockscout/pull/4931)                                                                                                                                                                                                                                                                                                      | (empty)                                                                            | v4.1.0+ |                | API, Indexer |
| `HEALTHY_BLOCKS_PERIOD`                                 |          | New blocks indexed max delay in /health API endpoint. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#2294](https://github.com/blockscout/blockscout/pull/2294/)                                                                                                                                                                                                                         | 5 m                                                                                | v2.0.2+ |                | API, Indexer |
| `NEW_TAGS`                                              |          | Add public tag labels. More info in [#6316](https://github.com/blockscout/blockscout/pull/6316)                                                                                                                                                                                                                                                                                                                                                   | (empty)                                                                            | v5.0.0+ |                | API          |
| `CUSTOM_CONTRACT_ADDRESSES_${tag_name}`                 |          | Specify addresses for some label. More info in [#6316](https://github.com/blockscout/blockscout/pull/6316)                                                                                                                                                                                                                                                                                                                                        | (empty)                                                                            | v5.0.0+ |                | API          |
| `SESSION_COOKIE_DOMAIN`                                 |          | Value of this env will be added to domain of session cookie. Implemented in [#6544](https://github.com/blockscout/blockscout/pull/6544)                                                                                                                                                                                                                                                                                                           | (empty)                                                                            | v5.0.0+ |                | API          |
| `DECODE_NOT_A_CONTRACT_CALLS`                           |          | Allows to decode contract calls directed to addresses which are not contracts. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                                                                                                                                                                                                         | `false`                                                                            | v5.1.0+ | ✅              | API          |
| `EIP_1559_ELASTICITY_MULTIPLIER`                        |          | EIP-1559 elasticity multiplier. Implemented in [#7253](https://github.com/blockscout/blockscout/pull/7253)                                                                                                                                                                                                                                                                                                                                        | 2                                                                                  | v5.1.3+ |                | API          |
| `EIP_1559_BASE_FEE_MAX_CHANGE_DENOMINATOR`              |          | EIP-1559 base fee max change denominator. Implemented in [#9202](https://github.com/blockscout/blockscout/pull/9202)                                                                                                                                                                                                                                                                                                                              | 8                                                                                  | v6.2.0+ |                | API          |
| `TOKEN_INSTANCE_OWNER_MIGRATION_CONCURRENCY`            |          | Concurrency of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                   | 5                                                                                  | v5.3.0+ |                | API, Indexer |
| `TOKEN_INSTANCE_OWNER_MIGRATION_BATCH_SIZE`             |          | Batch size of new fields backfiller implemented in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                    | 50                                                                                 | v5.3.0+ |                | API, Indexer |
| `TOKEN_INSTANCE_OWNER_MIGRATION_ENABLED`                |          | Enable of backfiller from [#8386](https://github.com/blockscout/blockscout/pull/8386) implemented in [#8752](https://github.com/blockscout/blockscout/pull/8752)                                                                                                                                                                                                                                                                                  | `false`                                                                            | v5.3.2+ |                | API, Indexer |
| `TOKEN_ID_MIGRATION_FIRST_BLOCK`                        |          | Bottom block for token id migration. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                                                                                   | 0                                                                                  | v5.0.0+ |                | API, Indexer |
| `TOKEN_ID_MIGRATION_CONCURRENCY`                        |          | Number of workers performing the token id migration. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                                                                   | 1                                                                                  | v5.0.0+ |                | API, Indexer |
| `TOKEN_ID_MIGRATION_BATCH_SIZE`                         |          | Interval of token transfer block numbers processed by a token id migration worker at a time. Implemented in [#6391](https://github.com/blockscout/blockscout/pull/6391)                                                                                                                                                                                                                                                                           | 500                                                                                | v5.0.0+ |                | API, Indexer |
| `ADDRESSES_TABS_COUNTERS_TTL`                           |          | TTL for cached tabs counters (works only for counters which are \< 51, if counter >= 51, then ttl == :infinity). Implemented in [#8512](https://github.com/blockscout/blockscout/pull/8512)                                                                                                                                                                                                                                                       | `10m`                                                                              | v5.3.0+ |                | API          |
| `API_INTERNAL_TRANSACTIONS_INDEXING_FINISHED_THRESHOLD` |          | In the case when the 1st tx in the chain already has internal transactions, If the number of blocks in pending\_block\_operations is less than the value in this env var, Blockscout will consider, that indexing of internal transactions finished, otherwise, it will consider, that indexing is still taking place and the indexing banner will appear at the top. Implemented in [#7576](https://github.com/blockscout/blockscout/pull/7576). | 1000                                                                               | v5.2.0+ |                | API          |
| `DATABASE_EVENT_URL`                                    |          | Variable to define the Postgres Database endpoint that will be used by event listener process. Applicable for separate indexer and API setup. More info in related PR. Implemented in [#10164](https://github.com/blockscout/blockscout/pull/10164).                                                                                                                                                                                              | (empty)                                                                            | v6.7.0+ |                | API          |

### Indexer management

| Variable                                                      | Required | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Default                                      | Version | Application  |
| ------------------------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- | ------- | ------------ |
| `BLOCK_TRANSFORMER`                                           |          | Transformer for blocks: base or clique.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | base                                         | v1.3.4+ | Indexer      |
| `DISABLE_INDEXER`                                             |          | If `true`, indexer application doesn't run.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | `false`                                      | v2.0.3+ | API, Indexer |
| `INDEXER_HIDE_INDEXING_PROGRESS_ALERT`                        |          | If `true`, indexer progress alert will be disabled even if initial catchup indexing is still in place. Implemented in [#7360](https://github.com/blockscout/blockscout/pull/7360).                                                                                                                                                                                                                                                                                                                                            | `false`                                      | v5.1.5+ | API          |
| `INDEXER_DISABLE_PENDING_TRANSACTIONS_FETCHER`                |          | If `true`, pending transactions fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | `false`                                      | v4.1.2+ | Indexer      |
| `INDEXER_DISABLE_INTERNAL_TRANSACTIONS_FETCHER`               |          | If `true`, internal transactions fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | `false`                                      | v4.1.2+ | Indexer      |
| `INDEXER_DISABLE_BLOCK_REWARD_FETCHER`                        |          | if `true`, block rewards fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | `false`                                      | v4.1.3+ | Indexer      |
| `INDEXER_DISABLE_ADDRESS_COIN_BALANCE_FETCHER`                |          | If `true`, coin balances fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | `false`                                      | v4.1.3+ | Indexer      |
| `INDEXER_DISABLE_CATALOGED_TOKEN_UPDATER_FETCHER`             |          | If `true`, cataloged tokens metadata fetcher is disabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | `false`                                      | v4.1.3+ | Indexer      |
| `INDEXER_MEMORY_LIMIT`                                        |          | Memory soft limit for the indexer.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | 1Gb                                          | v4.1.3+ | API, Indexer |
| `INDEXER_EMPTY_BLOCKS_SANITIZER_BATCH_SIZE`                   |          | Batch size for empty block sanitizer (re-fetcher).                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | 100                                          | v4.1.3+ | Indexer      |
| `INDEXER_CATCHUP_BLOCKS_BATCH_SIZE`                           |          | Batch size for blocks catchup fetcher. Implemented in [#6196](https://github.com/blockscout/blockscout/pull/6196).                                                                                                                                                                                                                                                                                                                                                                                                            | 10                                           | v5.0.0+ | Indexer      |
| `INDEXER_CATCHUP_BLOCKS_CONCURRENCY`                          |          | Concurrency for blocks catchup fetcher. Implemented in [#6196](https://github.com/blockscout/blockscout/pull/6196).                                                                                                                                                                                                                                                                                                                                                                                                           | 10                                           | v5.0.0+ | Indexer      |
| `INDEXER_DISABLE_EMPTY_BLOCKS_SANITIZER`                      |          | Empty blocks sanitizer is disabled if `true`                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | false                                        | v5.1.2+ | Indexer      |
| `DISABLE_REALTIME_INDEXER`                                    |          | If `true`, realtime fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | `false`                                      | v4.1.6+ | Indexer      |
| `FIRST_BLOCK`                                                 |          | The block number, where import of blocks by catchup fetcher begins from.                                                                                                                                                                                                                                                                                                                                                                                                                                                      | 0                                            | v1.3.8+ | API, Indexer |
| `LAST_BLOCK`                                                  |          | The block number, where import of blocks by catchup fetcher stops.                                                                                                                                                                                                                                                                                                                                                                                                                                                            | (empty)                                      | v2.0.3+ | Indexer      |
| `TRACE_FIRST_BLOCK`                                           |          | The block number, where indexing of internal transactions begins from.                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0                                            | v4.1.0+ | API, Indexer |
| `TRACE_LAST_BLOCK`                                            |          | The block number, where indexing of internal transactions stops.                                                                                                                                                                                                                                                                                                                                                                                                                                                              | (empty)                                      | v4.1.0+ | API, Indexer |
| `BLOCK_RANGES`                                                |          | Block ranges to import by catchup fetcher. Example: `BLOCK_RANGES="1..3,123..500,30..50,500..latest"`. Implemented in [#5783](https://github.com/blockscout/blockscout/pull/5783)                                                                                                                                                                                                                                                                                                                                             |                                              | v4.1.7+ | Indexer      |
| `FETCH_REWARDS_WAY`                                           |          | Tells the application how to calculate block rewards, by fetching via json\_rpc (`trace_block`) or manual by block params (`manual`).                                                                                                                                                                                                                                                                                                                                                                                         | trace\_block                                 | v4.1.4+ | Indexer      |
| `IPFS_GATEWAY_URL`                                            |          | IPFS gateway url for fetching token instances metadata from IPFS including token instance icon.                                                                                                                                                                                                                                                                                                                                                                                                                               | [https://ipfs.io/ipfs](https://ipfs.io/ipfs) | v5.3.0+ | Indexer      |
| `IPFS_GATEWAY_URL_PARAM_KEY`                                  |          | The key of the parameter to add to IPFS gateway url. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                                                              | (empty))                                     | v6.5.0+ | Indexer      |
| `IPFS_GATEWAY_URL_PARAM_VALUE`                                |          | The value of the parameter to add to IPFS gateway url. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                                                            | (empty))                                     | v6.5.0+ | Indexer      |
| `IPFS_GATEWAY_URL_PARAM_LOCATION`                             |          | Whether to add extra params: to query string or to the headers. Available values: query/header. Implemented in [#9898](https://github.com/blockscout/blockscout/pull/9898).                                                                                                                                                                                                                                                                                                                                                   | (empty))                                     | v6.5.0+ | Indexer      |
| `ETHEREUM_JSONRPC_DEBUG_TRACE_TRANSACTION_TIMEOUT`            |          | Timeout for `debug_traceTransaction`/`debug_traceBlockByNumber` JSON RPC method requests in case of `geth` archive node. Supported time formats: [https://pkg.go.dev/time#ParseDuration](https://pkg.go.dev/time#ParseDuration). Introduced in [#5505](https://github.com/blockscout/blockscout/pull/5505)                                                                                                                                                                                                                    | 5s                                           | v4.1.3+ | Indexer      |
| `ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES`                   |          | If `true`, all the requests with the method `eth_getBalance` with any block as parameter but `latest` are ignored. Implemented in [#6001](https://github.com/blockscout/blockscout/pull/6001)                                                                                                                                                                                                                                                                                                                                 | `false`                                      | v5.0.0+ | API, Indexer |
| `ETHEREUM_JSONRPC_PENDING_TRANSACTIONS_TYPE`                  |          | Defines which method will be used for fetching pending transactions: `default` - default method for fetching internal transactions for current `ETHEREUM_JSONRPC_VARIANT`, `geth` - `txpool_content` method will be used, `parity` - `parity_pendingTransactions` will be used. Implemented in [#6001](https://github.com/blockscout/blockscout/pull/6155)                                                                                                                                                                    | `default`                                    | v5.0.0+ | Indexer      |
| `INDEXER_INTERNAL_TRANSACTIONS_BATCH_SIZE`                    |          | Batch size for internal transactions fetcher. Implemented in [#6450](https://github.com/blockscout/blockscout/pull/6450).                                                                                                                                                                                                                                                                                                                                                                                                     | 10                                           | v5.0.0+ | Indexer      |
| `INDEXER_INTERNAL_TRANSACTIONS_CONCURRENCY`                   |          | Concurrency for internal transactions fetcher. Implemented in [#6450](https://github.com/blockscout/blockscout/pull/6450).                                                                                                                                                                                                                                                                                                                                                                                                    | 4                                            | v5.0.0+ | Indexer      |
| `INDEXER_BLOCK_REWARD_BATCH_SIZE`                             |          | Batch size for block reward fetcher. Implemented in [#6952](https://github.com/blockscout/blockscout/pull/6952).                                                                                                                                                                                                                                                                                                                                                                                                              | 10                                           | v5.1.2+ | Indexer      |
| `INDEXER_BLOCK_REWARD_CONCURRENCY`                            |          | Concurrency for block reward fetcher. Implemented in [#6952](https://github.com/blockscout/blockscout/pull/6952).                                                                                                                                                                                                                                                                                                                                                                                                             | 4                                            | v5.1.2+ | Indexer      |
| `INDEXER_RECEIPTS_BATCH_SIZE`                                 |          | Batch size for transaction receipts fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                      | 250                                          | v5.0.0+ | Indexer      |
| `INDEXER_RECEIPTS_CONCURRENCY`                                |          | Concurrency for transaction receipts fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                     | 10                                           | v5.0.0+ | Indexer      |
| `INDEXER_COIN_BALANCES_BATCH_SIZE`                            |          | Batch size for coin balances fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                             | 100                                          | v5.0.0+ | Indexer      |
| `INDEXER_COIN_BALANCES_CONCURRENCY`                           |          | Concurrency for coin balances fetcher. Implemented in [#6454](https://github.com/blockscout/blockscout/pull/6454).                                                                                                                                                                                                                                                                                                                                                                                                            | 4                                            | v5.0.0+ | Indexer      |
| `INDEXER_TOKEN_CONCURRENCY`                                   |          | Concurrency for token fetcher. Implemented in [#8167](https://github.com/blockscout/blockscout/pull/8167).                                                                                                                                                                                                                                                                                                                                                                                                                    | 10                                           | v5.2.2  | Indexer      |
| `INDEXER_TOKEN_BALANCES_BATCH_SIZE`                           |          | Batch size for token balances fetcher. Implemented in [#7439](https://github.com/blockscout/blockscout/pull/7439).                                                                                                                                                                                                                                                                                                                                                                                                            | 100                                          | v5.1.5+ | Indexer      |
| `INDEXER_TOKEN_BALANCES_CONCURRENCY`                          |          | Concurrency for token balances fetcher. Implemented in [#8167](https://github.com/blockscout/blockscout/pull/8167).                                                                                                                                                                                                                                                                                                                                                                                                           | 10                                           | v5.2.2  | Indexer      |
| `INDEXER_TX_ACTIONS_ENABLE`                                   |          | If `true`, transaction action indexer is active. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                                                                  | false                                        | v5.1.0+ | Indexer      |
| `INDEXER_TX_ACTIONS_MAX_TOKEN_CACHE_SIZE`                     |          | Maximum number of items in an internal cache of tx actions indexing process (to limit memory consumption). Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                        | 100000                                       | v5.1.0+ | Indexer      |
| `INDEXER_TX_ACTIONS_REINDEX_FIRST_BLOCK`                      |          | The first block of a block range for historical indexing or reindexing of tx actions. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                             | (empty)                                      | v5.1.0+ | Indexer      |
| `INDEXER_TX_ACTIONS_REINDEX_LAST_BLOCK`                       |          | The last block of a block range for historical indexing or reindexing of tx actions. Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582).                                                                                                                                                                                                                                                                                                                                                              | (empty)                                      | v5.1.0+ | Indexer      |
| `INDEXER_TX_ACTIONS_REINDEX_PROTOCOLS`                        |          | Comma-separated names of protocols which should be indexed or reindexed on historical blocks defined by the range. Example: `uniswap_v3,zkbob` - only these protocols will be indexed or reindexed for the defined block range. If the value is empty string (or not defined), all supported protocols will be indexed/reindexed. This option is not applicable to `realtime` and `catchup` fetchers (it always indexes all supported protocols). Implemented in [#6582](https://github.com/blockscout/blockscout/pull/6582). | (empty)                                      | v5.1.0+ | Indexer      |
| `INDEXER_TX_ACTIONS_AAVE_V3_POOL_CONTRACT`                    |          | Pool contract address for Aave v3 protocol. If not defined, Aave transaction actions are ignored by the indexer. Implemented in [#7185](https://github.com/blockscout/blockscout/pull/7185).                                                                                                                                                                                                                                                                                                                                  | (empty)                                      | v5.1.3+ | Indexer      |
| `INDEXER_TX_ACTIONS_UNISWAP_V3_FACTORY_CONTRACT`              |          | UniswapV3Factory contract address. Implemented in [#7312](https://github.com/blockscout/blockscout/pull/7312).                                                                                                                                                                                                                                                                                                                                                                                                                | 0x1F98431c8aD98523631AE4a59f267346ea31F984   | v5.1.4+ | Indexer      |
| `INDEXER_TX_ACTIONS_UNISWAP_V3_NFT_POSITION_MANAGER_CONTRACT` |          | NonfungiblePositionManager contract address for Uniswap v3. Implemented in [#7312](https://github.com/blockscout/blockscout/pull/7312).                                                                                                                                                                                                                                                                                                                                                                                       | 0xC36442b4a4522E871399CD717aBDD847Ab11FE88   | v5.1.4+ | Indexer      |
| `INDEXER_CATCHUP_MISSING_RANGES_BATCH_SIZE`                   |          | Batch size for missing ranges collector. Implemented in [#6583](https://github.com/blockscout/blockscout/pull/6583).                                                                                                                                                                                                                                                                                                                                                                                                          | 100000                                       | v5.0.0+ | Indexer      |
| `MIN_MISSING_BLOCK_NUMBER_BATCH_SIZE`                         |          | Batch size for min missing block number updater. Implemented in [#6583](https://github.com/blockscout/blockscout/pull/6583).                                                                                                                                                                                                                                                                                                                                                                                                  | 100000                                       | v5.0.0+ | API, Indexer |
| `INDEXER_INTERNAL_TRANSACTIONS_TRACER_TYPE`                   |          | Tracer type for `debug_traceTransaction`/`debug_traceBlockByNumber` requests for geth-like nodes. Possible values are: `js` to use custom Blockscout js tracer, `call_tracer` to use built-in `callTracer` geth tracer, `opcode` to use built-in `Struct/opcode logger` geth tracer, `polygon_edge` to work with Polygon edge nodes. Implemented in [#6721](https://github.com/blockscout/blockscout/pull/6721), [#7513](https://github.com/blockscout/blockscout/pull/7513)                                                  | `call_tracer`                                | v5.1.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_RETRY_MAX_REFETCH_INTERVAL`           |          | Maximum interval between attempts to fetch token instance metadata. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                     | `168h`                                       | v6.7.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_RETRY_EXPONENTIAL_TIMEOUT_BASE`       |          | Base to calculate exponential timeout. Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                                                                                                                                          | `2`                                          | v6.7.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_RETRY_EXPONENTIAL_TIMEOUT_COEFF`      |          | Coefficient to calculate exponential timeout. Implemented in [#10027](https://github.com/blockscout/blockscout/pull/10027).                                                                                                                                                                                                                                                                                                                                                                                                   | `100`                                        | v6.7.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_RETRY_CONCURRENCY`                    |          | Concurrency for `retry` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                   | 10                                           | v5.1.4+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_REALTIME_CONCURRENCY`                 |          | Concurrency for `realtime` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                | 10                                           | v5.1.4+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_SANITIZE_CONCURRENCY`                 |          | Concurrency for `sanitize` token instance fetcher. Implemented in [#7286](https://github.com/blockscout/blockscout/pull/7286).                                                                                                                                                                                                                                                                                                                                                                                                | 10                                           | v5.1.4+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_RETRY_FETCHER`                |          | If `true`, `retry` token instance fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | `false`                                      | v5.1.4+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_REALTIME_FETCHER`             |          | If `true`, `realtime` token instance fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | `false`                                      | v5.1.4+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_ENABLED`               |          | If `true`, `realtime` token instance fetcher will retry once on 404 and 500 error. Implemented in [#10036](https://github.com/blockscout/blockscout/pull/10036).                                                                                                                                                                                                                                                                                                                                                              | `false`                                      | v6.6.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_TIMEOUT`               |          | Timeout for retry set by `INDEXER_TOKEN_INSTANCE_REALTIME_RETRY_ENABLED`. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#10036](https://github.com/blockscout/blockscout/pull/10036).                                                                                                                                                                                                                                                                               | `5s`                                         | v6.6.0+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_SANITIZE_FETCHER`             |          | If `true`, `sanitize` token instance fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | `false`                                      | v5.1.4+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_USE_BASE_URI_RETRY`                   |          | If `true`, and request to `tokenURI(tokenId)` failed with `VM execution error`, Blockscout will make request to `baseURI` and try to request metadata from baseURI + tokenId                                                                                                                                                                                                                                                                                                                                                  | `false`                                      | v6.2.0+ | Indexer      |
| `INDEXER_REALTIME_FETCHER_MAX_GAP`                            |          | Max gap between consecutive `latest` blocks that will be filled by realtime fetcher. Implemented in [#7393](https://github.com/blockscout/blockscout/pull/7393)                                                                                                                                                                                                                                                                                                                                                               | 1000                                         | v5.1.5+ | Indexer      |
| `INDEXER_DISABLE_WITHDRAWALS_FETCHER`                         |          | If `true`, withdrawals fetcher is disabled. Implemented in [#6694](https://github.com/blockscout/blockscout/pull/6694).                                                                                                                                                                                                                                                                                                                                                                                                       | `true`                                       | v5.1.5+ | Indexer      |
| `WITHDRAWALS_FIRST_BLOCK`                                     |          | The block number, where import of withdrawals by catchup fetcher begins from. Should be the block where withdrawals upgrade occurred on the chain. Implemented in [#6694](https://github.com/blockscout/blockscout/pull/6694).                                                                                                                                                                                                                                                                                                | (empty)                                      | v5.1.5+ | Indexer      |
| `INDEXER_CATCHUP_BLOCK_INTERVAL`                              |          | Interval between blocks catchup fetcher tasks. Implemented in [#7489](https://github.com/blockscout/blockscout/pull/7489).                                                                                                                                                                                                                                                                                                                                                                                                    | `5s`                                         | v5.1.5+ | Indexer      |
| `INDEXER_FETCHER_INIT_QUERY_LIMIT`                            |          | Limit for all fetchers init queries. Implemented in [#7697](https://github.com/blockscout/blockscout/pull/7697).                                                                                                                                                                                                                                                                                                                                                                                                              | 100                                          | v5.2.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_RETRY_BATCH_SIZE`                     |          | Batch size for `retry` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313)                                                                                                                                                                                                                                                                                                                                                                                                     | 10                                           | v5.2.3+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_REALTIME_BATCH_SIZE`                  |          | Batch size for `realtime` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313).                                                                                                                                                                                                                                                                                                                                                                                                 | 1                                            | v5.2.3+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_SANITIZE_BATCH_SIZE`                  |          | Batch size for `sanitize` token instance fetcher. Implemented in [#8313](https://github.com/blockscout/blockscout/pull/8313).                                                                                                                                                                                                                                                                                                                                                                                                 | 10                                           | v5.2.3+ | Indexer      |
| `INDEXER_TOKEN_BALANCES_FETCHER_INIT_QUERY_LIMIT`             |          | Limit for token balance fetcher init queries. Implemented in [#8459](https://github.com/blockscout/blockscout/pull/8459).                                                                                                                                                                                                                                                                                                                                                                                                     | 100000                                       | v5.2.3+ | Indexer      |
| `INDEXER_COIN_BALANCES_FETCHER_INIT_QUERY_LIMIT`              |          | Limit for coin balance fetcher init queries. Implemented in [#7996](https://github.com/blockscout/blockscout/pull/7996).                                                                                                                                                                                                                                                                                                                                                                                                      | 2000                                         | v5.3.0+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_LEGACY_SANITIZE_FETCHER`      |          | If `true`, legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                      | `true`                                       | v5.3.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_LEGACY_SANITIZE_CONCURRENCY`          |          | Concurrency for legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                 | 2                                            | v5.4.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_LEGACY_SANITIZE_BATCH_SIZE`           |          | Batch size for legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                  | 10                                           | v5.3.0+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_ERC_1155_SANITIZE_FETCHER`    |          | If `true`, `erc-1155-sanitize` token instance fetcher doesn't run. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                | `false`                                      | v6.2.0+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_ERC_721_SANITIZE_FETCHER`     |          | If `true`, `erc-721-sanitize` token instance fetcher doesn't run. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                 | `false`                                      | v6.2.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_ERC_1155_SANITIZE_CONCURRENCY`        |          | Concurrency for `erc-1155-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                       | 2                                            | v6.2.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_ERC_721_SANITIZE_CONCURRENCY`         |          | Concurrency for `erc-721-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                        | 2                                            | v6.2.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_ERC_1155_SANITIZE_BATCH_SIZE`         |          | Batch size for `erc-1155-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                        | 10                                           | v6.2.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_ERC_721_SANITIZE_BATCH_SIZE`          |          | Batch size for `erc-721-sanitize` token instance fetcher. Implemented in [#9226](https://github.com/blockscout/blockscout/pull/9226).                                                                                                                                                                                                                                                                                                                                                                                         | 10                                           | v6.2.0+ | Indexer      |
| `INDEXER_EMPTY_BLOCKS_SANITIZER_INTERVAL`                     |          | Interval for empty block sanitizer. Implemented in [#8658](https://github.com/blockscout/blockscout/pull/8658)                                                                                                                                                                                                                                                                                                                                                                                                                | `5m`                                         | v5.3.0+ | Indexer      |
| `ETHEREUM_JSONRPC_ARCHIVE_BALANCES_WINDOW`                    |          | Max block number gap from latest for which balances requests can be processed when `ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES` env var is set to `true`. Implemented in [#8673](https://github.com/blockscout/blockscout/pull/8673)                                                                                                                                                                                                                                                                                           | 200                                          | v5.3.1+ | API, Indexer |
| `DISABLE_CATCHUP_INDEXER`                                     |          | If `true`, catchup fetcher doesn't run                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | `false`                                      | v5.3.2+ | Indexer      |
| `TRACE_BLOCK_RANGES`                                          |          | Block ranges for traceable blocks. Example: `TRACE_BLOCK_RANGES="1..3,123..500,30..50,500..latest"`. Implemented in [#8960](https://github.com/blockscout/blockscout/pull/8960)                                                                                                                                                                                                                                                                                                                                               | (empty)                                      | v5.4.0+ | API, Indexer |
| `ETHEREUM_JSONRPC_GETH_TRACE_BY_BLOCK`                        |          | Enable tracing by block for geth variant. Implemented in [#9072](https://github.com/blockscout/blockscout/pull/9072)                                                                                                                                                                                                                                                                                                                                                                                                          | `false`                                      | v6.1.0+ | Indexer      |
| `INDEXER_GRACEFUL_SHUTDOWN_PERIOD`                            |          | Time that will be given to the block fetchers when stopping the application before they are killed. Implemented in [#9729](https://github.com/blockscout/blockscout/pull/9729)                                                                                                                                                                                                                                                                                                                                                | `5m`                                         | v6.5.0+ | Indexer      |
| `MISSING_BALANCE_OF_TOKENS_WINDOW_SIZE`                       |          | Minimal blocks count until the next token balance request will be executed for tokens that doesn't implement `balanceOf` function. Implemented in [#10142](https://github.com/blockscout/blockscout/pull/10142)                                                                                                                                                                                                                                                                                                               | 100                                          | v6.7.0+ | Indexer      |
| `ETHEREUM_JSONRPC_GETH_ALLOW_EMPTY_TRACES`                    |          | Allow transactions to not have internal transactions. Implemented in [#10200](https://github.com/blockscout/blockscout/pull/10200)                                                                                                                                                                                                                                                                                                                                                                                            | `false`                                      | v6.7.0+ | Indexer      |
| `INDEXER_DISABLE_TOKEN_INSTANCE_LEGACY_SANITIZE_FETCHER`      |          | If `true`, legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                      | `true`                                       | v5.3.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_LEGACY_SANITIZE_CONCURRENCY`          |          | Concurrency for legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                 | 2                                            | v5.4.0+ | Indexer      |
| `INDEXER_TOKEN_INSTANCE_LEGACY_SANITIZE_BATCH_SIZE`           |          | Batch size for legacy `sanitize` token instance fetcher doesn't run. Appeared in [#8386](https://github.com/blockscout/blockscout/pull/8386)                                                                                                                                                                                                                                                                                                                                                                                  | 10                                           | v5.3.0+ | Indexer      |

### Denormalization management

| Variable                                          | Required | Description                                                                             | Default | Version | Application  |
| ------------------------------------------------- | -------- | --------------------------------------------------------------------------------------- | ------- | ------- | ------------ |
| `DENORMALIZATION_MIGRATION_BATCH_SIZE`            |          | Number of transactions to denormalize (add block timestamp and consensus) in the batch. | 500     | v6.0.0+ | API, Indexer |
| `DENORMALIZATION_MIGRATION_CONCURRENCY`           |          | Number of parallel denormalization transaction batches processing.                      | 10      | v6.0.0+ | API, Indexer |
| `TOKEN_TRANSFER_TOKEN_TYPE_MIGRATION_BATCH_SIZE`  |          | Number of token transfers to denormalize (add token\_type) in the batch.                | 100     | v6.3.0+ | API, Indexer |
| `TOKEN_TRANSFER_TOKEN_TYPE_MIGRATION_CONCURRENCY` |          | Number of parallel denormalization token transfer batches processing.                   | 1       | v6.3.0+ | API, Indexer |
| `SANITIZE_INCORRECT_NFT_BATCH_SIZE`               |          | Number of token transfers to sanitize in the batch.                                     | 100     | v6.3.0+ | API, Indexer |
| `SANITIZE_INCORRECT_NFT_CONCURRENCY`              |          | Number of parallel sanitizing token transfer batches processing.                        | 1       | v6.3.0+ | API, Indexer |

### Sanitizers management

| Variable                              | Required | Description                                                                                                                                   | Default | Version | Application  |
| ------------------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ------------ |
| `SANITIZE_INCORRECT_WETH_BATCH_SIZE`  |          | Number of token transfers to sanitize in the batch. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134)              | 100     | v6.7.0+ | API, Indexer |
| `SANITIZE_INCORRECT_WETH_CONCURRENCY` |          | Number of parallel sanitizing token transfer batches processing. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134) | 1       | v6.7.0+ | API, Indexer |

### Ethereum Management

| Variable                                          | Required | Description                                                                                                                                                                                                                                                                                             | Default                | Version | Application |
| ------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------- | ------- | ----------- |
| `INDEXER_BEACON_RPC_URL`                          |          | The Beacon Chain RPC endpoint used to fetch blob sidecars. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                | http\://localhost:5052 | v6.2.0+ | Indexer     |
| `INDEXER_DISABLE_BEACON_BLOB_FETCHER`             |          | If `true` the fetcher of Beacon data blobs won't be started, new transaction and block fields still will be extracted. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                      | false                  | v6.2.0+ | Indexer     |
| `INDEXER_BEACON_BLOB_FETCHER_SLOT_DURATION`       |          | Slot duration in the Beacon Chain in seconds. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                                                                             | 12                     | v6.2.0+ | Indexer     |
| `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT`      |          | Any past finalized Beacon Chain slot number. Used as reference for blob inclusion slot calculations. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                                      | 8000000                | v6.2.0+ | Indexer     |
| `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_TIMESTAMP` |          | UTC timestamp of the Beacon Chain slot specified in `INDEXER_BEACON_BLOB_FETCHER_REFERENCE_SLOT`. Used as reference for blob inclusion slot calculations. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168). | 1702824023             | v6.2.0+ | Indexer     |
| `INDEXER_BEACON_BLOB_FETCHER_START_BLOCK`         |          | Beacon Chain blob fetcher start block. On start-up, indexer will only look for missed blobs beyond this block number. It's recommended to set this block to the first block after the Dencun hardfork. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                      | 19200000               | v6.2.0+ | Indexer     |
| `INDEXER_BEACON_BLOB_FETCHER_END_BLOCK`           |          | Beacon Chain blob fetcher end block. On start-up, indexer will only look for missed blobs before this block number. If set to `0`, then all recent till `latest` will be traversed. Implemented in [#9168](https://github.com/blockscout/blockscout/pull/9168).                                         | 0                      | v6.2.0+ | Indexer     |

### Polygon Edge Management

| Variable                                          | Required | Description                                                                                                                                                                                                                                                                                                                                             | Default | Version | Application |
| ------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `INDEXER_POLYGON_EDGE_L1_RPC`                     |          | The RPC endpoint for L1 used to fetch deposit or withdrawal events. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                         | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L1_EXIT_HELPER_CONTRACT`    |          | The address of ExitHelper contract on L1 (root chain) used to fetch withdrawal exits. Required for withdrawal events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                              | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L1_WITHDRAWALS_START_BLOCK` |          | The number of start block on L1 (root chain) to index withdrawal exits. If the table of withdrawal exits is not empty, the process will continue indexing from the last indexed message. If empty or not defined, the withdrawal exits are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                     | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L1_STATE_SENDER_CONTRACT`   |          | The address of StateSender contract on L1 (root chain) used to fetch deposits. Required for deposit events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                        | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L1_DEPOSITS_START_BLOCK`    |          | The number of start block on L1 (root chain) to index deposits. If the table of deposits is not empty, the process will continue indexing from the last indexed message. If empty or not defined, the deposits are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                             | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L2_STATE_SENDER_CONTRACT`   |          | The address of L2StateSender contract on L2 (child chain) used to fetch withdrawals. Required for withdrawal events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                               | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L2_WITHDRAWALS_START_BLOCK` |          | The number of start block on L2 (child chain) to index withdrawals. If the table of withdrawals is not empty, the process will fill gaps and then continue indexing from the last indexed message. If empty or not defined, the withdrawals are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L2_STATE_RECEIVER_CONTRACT` |          | The address of StateReceiver contract on L2 (child chain) used to fetch deposit executes. Required for deposit events indexing. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                             | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_L2_DEPOSITS_START_BLOCK`    |          | The number of start block on L2 (child chain) to index deposit executes. If the table of deposit executes is not empty, the process will fill gaps and then continue indexing from the last indexed message. If empty or not defined, the deposit executes are not indexed. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180). | (empty) | v5.3.0+ | Indexer     |
| `INDEXER_POLYGON_EDGE_ETH_GET_LOGS_RANGE_SIZE`    |          | Block range size for eth\_getLogs request in Polygon Edge indexer modules. Implemented in [#8180](https://github.com/blockscout/blockscout/pull/8180).                                                                                                                                                                                                  | (empty) | v5.3.0+ | Indexer     |

### Rootstock management

| Variable                                       | Required | Description                                                                                                                                                                                                                                                            | Default | Version | Application |
| ---------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `ROOTSTOCK_REMASC_ADDRESS`                     |          | The address hash of remasc address on Rootstock chain. Implemented in [#8542](https://github.com/blockscout/blockscout/pull/8542).                                                                                                                                     |         | v5.3.0+ | API         |
| `ROOTSTOCK_BRIDGE_ADDRESS`                     |          | The address hash of bridge address on Rootstock chain. Implemented in [#8542](https://github.com/blockscout/blockscout/pull/8542).                                                                                                                                     |         | v5.3.0+ | API         |
| `INDEXER_DISABLE_ROOTSTOCK_DATA_FETCHER`       |          | If `true` the fetcher of Rootstock specific fields for blocks that are already in the database won't be started, fields from new blocks will be extracted. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                 |         | v5.3.2+ | Indexer     |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_INTERVAL`      |          | The interval between fetching the next `INDEXER_ROOTSTOCK_DATA_FETCHER_DB_BATCH_SIZE` blocks from the database and the node, used to configure the load on the database and JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742). |         | v5.3.2+ | Indexer     |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_BATCH_SIZE`    |          | The number of requests in one JSON-RPC batch request, used to configure the load or RPS on JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                                  |         | v5.3.2+ | Indexer     |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_CONCURRENCY`   |          | The number of simultaneous requests to the JSON-RPC node, used to configure the load or RPS on JSON-RPC node. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                              |         | v5.3.2+ | Indexer     |
| `INDEXER_ROOTSTOCK_DATA_FETCHER_DB_BATCH_SIZE` |          | The number of blocks that are fetched from the database in one database query. Implemented in [#8742](https://github.com/blockscout/blockscout/pull/8742).                                                                                                             |         | v5.3.2+ | Indexer     |

### Shibarium Management

| Variable                                          | Required | Description                                                                                                                                                                                                                                                                                                | Default | Version | Application |
| ------------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `INDEXER_SHIBARIUM_L1_RPC`                        |          | The RPC endpoint for L1 used to fetch deposit or withdrawal events. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                                                            | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_START_BLOCK`                |          | The number of start block on L1 to index L1 events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L1 event. If empty or not defined, the L1 events are not handled. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929). | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_DEPOSIT_MANAGER_CONTRACT`   |          | The address of DepositManagerProxy contract on L1 used to fetch BONE token deposits. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                          | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_ETHER_PREDICATE_CONTRACT`   |          | The address of EtherPredicateProxy contract on L1 used to fetch ETH deposits and withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                 | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_ERC20_PREDICATE_CONTRACT`   |          | The address of ERC20PredicateProxy contract on L1 used to fetch ERC20 token deposits and withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                         | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_ERC721_PREDICATE_CONTRACT`  |          | The address of ERC721PredicateProxy contract on L1 used to fetch ERC721 token deposits and withdrawals. Optional for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                       | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_ERC1155_PREDICATE_CONTRACT` |          | The address of ERC1155PredicateProxy contract on L1 used to fetch ERC1155 token deposits and withdrawals. Optional for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                     | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L1_WITHDRAW_MANAGER_CONTRACT`  |          | The address of WithdrawManagerProxy contract on L1 used to fetch BONE token withdrawals. Required for L1 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                      | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L2_START_BLOCK`                |          | The number of start block on L2 to index L2 events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L2 event. If empty or not defined, the L2 events are not handled. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929). | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L2_CHILD_CHAIN_CONTRACT`       |          | The address of ChildChain contract on L2 used to fetch BONE token deposits. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                   | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L2_WETH_CONTRACT`              |          | The address of WETH contract on L2 used to fetch ETH deposits and withdrawals. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                                                | (empty) | v6.1.0+ | Indexer     |
| `INDEXER_SHIBARIUM_L2_BONE_WITHDRAW_CONTRACT`     |          | The address of a contract which emits `Withdraw` event on L2. Used to fetch BONE token withdrawals. Required for L2 events indexing. Implemented in [#8929](https://github.com/blockscout/blockscout/pull/8929).                                                                                           | (empty) | v6.1.0+ | Indexer     |

### Polygon zkEVM Rollup management

| Variable                                          | Required | Description                                                                                                                                                                                                                                                                                                                                                           | Default | Version | Application |
| ------------------------------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `INDEXER_POLYGON_ZKEVM_BATCHES_ENABLED`           |          | Enables Polygon zkEVM batches fetcher. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                                    | `false` | v5.3.1+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_BATCHES_CHUNK_SIZE`        |          | The number of Polygon zkEVM batches in one chunk when reading them from RPC. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                              | 20      | v5.3.1+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_BATCHES_RECHECK_INTERVAL`  |          | The latest batch rechecking interval, seconds. Implemented in [#7584](https://github.com/blockscout/blockscout/pull/7584).                                                                                                                                                                                                                                            | 60      | v5.3.1+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_RPC`                    |          | The RPC endpoint for L1 used to fetch Deposit or Withdrawal bridge events. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                                                                |         | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK`     |          | The number of a start block on L1 to index L1 bridge events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L1 event. If empty or not defined, the L1 events are not handled. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                   |         | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_CONTRACT`        |          | The address of PolygonZkEVMBridgeV2 contract on L1 used to fetch L1 bridge events. Required for L1 bridge events indexing. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                |         | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NETWORK_ID`      |          | L1 Network ID in terms of Polygon zkEVM bridge (0 = Ethereum Mainnet, 1 = Polygon zkEVM, 2 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                   |         | v6.4.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_ROLLUP_INDEX`    |          | L1 Rollup index in terms of Polygon zkEVM bridge (0 = Polygon zkEVM, 1 = Astar zkEVM, etc.). Not defined if L1 is Ethereum Mainnet. Required if L1 is not Ethereum Mainnet and `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637). |         | v6.4.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NATIVE_SYMBOL`   |          | The symbol of the native coin on L1 to display it in the table of the bridge Deposits and Withdrawals on UI. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                              | ETH     | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_NATIVE_DECIMALS` |          | The number of decimals to correctly display an amount of native coins for some Deposit or Withdrawal bridge operations on UI. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                             | 18      | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK`     |          | The number of a start block on L2 to index L2 bridge events. If the table of bridge operations is not empty, the process will continue indexing from the last indexed L2 event. If empty or not defined, the L2 events are not handled. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                   |         | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_CONTRACT`        |          | The address of PolygonZkEVMBridgeV2 contract on L2 used to fetch L2 bridge events. Required for L2 bridge events indexing. Implemented in [#9098](https://github.com/blockscout/blockscout/pull/9098).                                                                                                                                                                |         | v6.2.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_NETWORK_ID`      |          | L2 Network ID in terms of Polygon zkEVM bridge (1 = Polygon zkEVM, 2 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                                         |         | v6.4.0+ | Indexer     |
| `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_ROLLUP_INDEX`    |          | L2 Rollup index in terms of Polygon zkEVM bridge (0 = Polygon zkEVM, 1 = Astar zkEVM, etc.). Required if `INDEXER_POLYGON_ZKEVM_L1_BRIDGE_START_BLOCK` or `INDEXER_POLYGON_ZKEVM_L2_BRIDGE_START_BLOCK` is defined. Implemented in [#9637](https://github.com/blockscout/blockscout/pull/9637).                                                                       |         | v6.4.0+ | Indexer     |

### Optimism Rollup Management

Please note that these Optimism-related variables are only supported together with setting `CHAIN_TYPE=optimism`.

| Variable                                             | Required | Description                                                                                                                                                                                                                                                                                                                                                                                                                                              | Default | Version | Application |
| ---------------------------------------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `INDEXER_OPTIMISM_L1_RPC`                            |          | The RPC endpoint for L1 used to fetch transaction batches, output roots, deposits, or withdrawal events. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                     | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_PORTAL_CONTRACT`                |          | The address of OptimismPortal contract on L1 used to fetch deposits and withdrawal events. Required for deposits and withdrawal events indexing. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                             | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK`              |          | The number of start block on L1 to index transaction batches. If the table of batches is not empty, the process will continue indexing from the last indexed batch. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                          | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_BATCH_INBOX`                    |          | The inbox address to index transaction batches on L1. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                      | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_BATCH_SUBMITTER`                |          | The batch submitter address to index transaction batches on L1. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                            | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_BATCH_BLOCKSCOUT_BLOBS_API_URL` |          | Defines a URL to Blockscout Blobs API to retrieve L1 blobs from that. Example for Sepolia: `https://eth-sepolia.blockscout.com/api/v2/blobs`. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is not empty. Implemented in [#9571](https://github.com/blockscout/blockscout/pull/9571).                                                                                                                                                              | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_BATCH_BLOCKS_CHUNK_SIZE`        |          | Blocks chunk size to send batch RPC requests. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                                                                                                                | 4       | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L2_BATCH_GENESIS_BLOCK_NUMBER`     |          | L2 genesis block number for Optimism chain. Required if `INDEXER_OPTIMISM_L1_BATCH_START_BLOCK` is defined. The block number can be found at [superchain registry](https://github.com/ethereum-optimism/superchain-registry/tree/main/superchain/configs). [Example](https://github.com/ethereum-optimism/superchain-registry/blob/main/superchain/configs/mainnet/op.yaml). Implemented in [#9260](https://github.com/blockscout/blockscout/pull/9260). | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_OUTPUT_ROOTS_START_BLOCK`       |          | The number of start block on L1 to index output roots. If the table of output roots is not empty, the process will continue indexing from the last indexed root. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                             | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_OUTPUT_ORACLE_CONTRACT`         |          | The address of OutputOracle contract on L1 used to fetch output roots. Required for output roots indexing when `INDEXER_OPTIMISM_L1_OUTPUT_ROOTS_START_BLOCK` is not empty. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                  | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_DEPOSITS_START_BLOCK`           |          | The number of the L1 block from which deposits will be fetched. Implemented in [#6993](https://github.com/blockscout/blockscout/pull/6993).                                                                                                                                                                                                                                                                                                              | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_DEPOSITS_BATCH_SIZE`            |          | Number of blocks in a single `eth_getLogs` request. Implemented in [#6993](https://github.com/blockscout/blockscout/pull/6993).                                                                                                                                                                                                                                                                                                                          | 500     | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L1_WITHDRAWALS_START_BLOCK`        |          | The number of start block on L1 to index withdrawal events. If the table of withdrawal events is not empty, the process will continue indexing from the last indexed withdrawal event. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                       | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L2_WITHDRAWALS_START_BLOCK`        |          | The number of start block on L2 to index withdrawals. If the table of withdrawals is not empty, the process will continue indexing from the last indexed withdrawal. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                         | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_OPTIMISM_L2_MESSAGE_PASSER_CONTRACT`        |          | The address of L2ToL1MessagePasser contract to index withdrawals. Required if `INDEXER_OPTIMISM_L2_WITHDRAWALS_START_BLOCK` is not empty. Implemented in [#6980](https://github.com/blockscout/blockscout/pull/6980).                                                                                                                                                                                                                                    | (empty) | v6.3.0+ | Indexer     |

### zkSync Rollup Management

Please note that these zkSync-related variables are only supported together with setting `CHAIN_TYPE=zksync`.

| Variable                                         | Required | Description                                                                                                                                                     | Default | Version | Application |
| ------------------------------------------------ | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `INDEXER_ZKSYNC_BATCHES_ENABLED`                 |          | Enables Polygon zkEVM batches fetcher. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                              | `false` | v6.3.0+ | Indexer     |
| `INDEXER_ZKSYNC_BATCHES_CHUNK_SIZE`              |          | The number of RPC calls in one request when reading data from RPC. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                  | 50      | v6.3.0+ | Indexer     |
| `INDEXER_ZKSYNC_NEW_BATCHES_MAX_RANGE`           |          | Maximum amount of batches requested if Blockscout does not have all batches synced. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080). | 50      | v6.3.0+ | Indexer     |
| `INDEXER_ZKSYNC_NEW_BATCHES_RECHECK_INTERVAL`    |          | The latest batch rechecking interval, seconds. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                      | 60      | v6.3.0+ | Indexer     |
| `INDEXER_ZKSYNC_L1_RPC`                          |          | The RPC endpoint for L1 used to fetch status of batches. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                            | (empty) | v6.3.0+ | Indexer     |
| `INDEXER_ZKSYNC_BATCHES_STATUS_RECHECK_INTERVAL` |          | The batches status rechecking interval, seconds. Implemented in [#9080](https://github.com/blockscout/blockscout/pull/9080).                                    | 60      | v6.3.0+ | Indexer     |

### Arbitrum Rollup Management

Please note that these Arbitrum-related variables are only supported together with setting `CHAIN_TYPE=arbitrum`.

| Variable                                                          | Required | Description                                                                                                                                                                                                                                                                                                                                                                                                    | Default                                      | Version |
| ----------------------------------------------------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- | ------- |
| `INDEXER_ARBITRUM_ARBSYS_CONTRACT`                                |          | The address of ArbSys contract on the rollup. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                      | `0x0000000000000000000000000000000000000064` |         |
| `INDEXER_ARBITRUM_L1_RPC`                                         |          | The RPC endpoint for L1 used to fetch transaction batches, block confirmations, and cross-chain messages. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                          |                                              |         |
| `INDEXER_ARBITRUM_L1_RPC_CHUNK_SIZE`                              |          | The number of RPC calls in one request when reading data from RPC. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                 | 20                                           |         |
| `INDEXER_ARBITRUM_L1_RPC_HISTORICAL_BLOCKS_RANGE`                 |          | The block range size for the eth\_getLogs request. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                 | 1000                                         |         |
| `INDEXER_ARBITRUM_L1_ROLLUP_CONTRACT`                             |          | The Arbitrum Rollup contract address on L1. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                                        |                                              |         |
| `INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK`                           |          | The block number where the Arbitrum rollup contract has been deployed. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                             | 1                                            |         |
| `INDEXER_ARBITRUM_L1_COMMON_START_BLOCK`                          |          | The block number at which synchronization will commence. It will proceed in both directions: discovering new batches up to the chain head, and historical batches until `INDEXER_ARBITRUM_L1_ROLLUP_INIT_BLOCK`. If omitted, the synchronization starts from the latest block. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                     | latest block                                 |         |
| `INDEXER_ARBITRUM_ROLLUP_CHUNK_SIZE`                              |          | The number of RPC calls in one request when reading data from RPC. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                                 | 20                                           |         |
| `INDEXER_ARBITRUM_BRIDGE_MESSAGES_TRACKING_ENABLED`               |          | Enables monitoring on L1 of cross-chain messages directed to L2 and catchup on L2 of historical cross-chain messages. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                              |                                              |         |
| `INDEXER_ARBITRUM_MISSED_MESSAGES_RECHECK_INTERVAL`               |          | Interval to re-check on the rollup historical messages directed to and from the rollup, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                | 3600                                         |         |
| `INDEXER_ARBITRUM_MISSED_MESSAGES_TO_L2_BLOCK_DEPTH`              |          | Amount of L2 blocks to revisit to identify historical L1-to-L2 messages in the messages catchup task by handling block transactions. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                               | 50                                           |         |
| `INDEXER_ARBITRUM_MISSED_MESSAGES_TO_L1_BLOCK_DEPTH`              |          | Amount of L2 blocks to revisit to identify historical L2-to-L1 messages in the messages catchup task by handling logs in receipts. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                 | 1000                                         |         |
| `INDEXER_ARBITRUM_TRACKING_MESSAGES_ON_L1_RECHECK_INTERVAL`       |          | Interval to re-check on L1 new messages directed to the rollup, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                                        | 20                                           |         |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_ENABLED`                       |          | Enables monitoring of transaction batches, block confirmations, and L2-to-L1 messages executions. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                  |                                              |         |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_RECHECK_INTERVAL`              |          | Interval to re-check on L1 new and historical batches, confirmations, and executions, in seconds. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                                                  | 20                                           |         |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_L1_FINALIZATION_CHECK_ENABLED` |          | Whether L1 transactions related to batches, confirmations, and executions need to be monitored for finalization or not. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                                            | `false`                                      |         |
| `INDEXER_ARBITRUM_BATCHES_TRACKING_MESSAGES_TO_BLOCKS_SHIFT`      |          | Difference between the message count and actual rollup block numbers in the SequencerBatchDelivered event on L1. Applicable for ArbitrumOne only. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                                                                                                                                  | 0                                            |         |
| `INDEXER_ARBITRUM_CONFIRMATIONS_TRACKING_FINALIZED`               |          | Whether to choose `safe` (true) or `latest` (false) block to discover new confirmations. This setting is required to reduce latency between the actual confirmation transaction and its discovery. Recommended to have true on rollups which use Ethereum Mainnet as L1. Determines how fast new confirmations will be discovered. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312). | `true`                                       |         |
| `INDEXER_ARBITRUM_NEW_BATCHES_LIMIT`                              |          | The number of batches to be handled and imported at once. This is applicable for cases when dozens of batches are found in one discovery iteration, and it is necessary to import them in chunks to avoid the entire process being aborted if any errors occur. Implemented in [#9312](https://github.com/blockscout/blockscout/pull/9312).                                                                    | 10                                           |         |

### Exchange rates management

| Variable                                             | Required | Description                                                                                                                                                                                                                                                                                       | Default          | Version | Application  |
| ---------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- | ------- | ------------ |
| `DISABLE_EXCHANGE_RATES`                             |          | Disables or enables fetching of coin price from Coingecko API.                                                                                                                                                                                                                                    | false            | v3.1.2+ | API, Indexer |
| `EXCHANGE_RATES_MARKET_CAP_SOURCE`                   |          | This environment variable is used to set source for market cap fetching. Available values `coin_gecko`, `mobula`, `coin_market_cap`.                                                                                                                                                              | `coin_gecko`     | v5.2.3+ | API, Indexer |
| `EXCHANGE_RATES_TVL_SOURCE`                          |          | This environment variable is used to set source for TVL fetching. Available value is `defillama`.                                                                                                                                                                                                 | (empty)          | v5.3.0+ | API, Indexer |
| `EXCHANGE_RATES_PRICE_SOURCE`                        |          | This environment variable is used to set source for price fetching. Available values are also `crypto_compare`, `coin_gecko`, `mobula` and `coin_market_cap`.                                                                                                                                     | `crypto_compare` | v5.2.3+ | API, Indexer |
| `EXCHANGE_RATES_MOBULA_COIN_ID`                      |          | Explicitly set Mobula coin ID.                                                                                                                                                                                                                                                                    | (empty)          | v6.7.0+ | API, Indexer |
| `EXCHANGE_RATES_MOBULA_SECONDARY_COIN_ID`            |          | Explicitly set Mobula coin ID for secondary coin market chart.                                                                                                                                                                                                                                    | (empty)          | v6.7.0+ | API, Indexer |
| `EXCHANGE_RATES_MOBULA_API_KEY`                      |          | Mobula API key.                                                                                                                                                                                                                                                                                   | (empty)          | v6.7.0+ | API, Indexer |
| `EXCHANGE_RATES_MOBULA_CHAIN_ID`                     |          | [Mobula](https://www.mobula.io/) chain id for which token prices are fetched, see full list in the [`Documentation`](https://docs.mobula.io/blockchains/intro-blockchains).                                                                                                                       | ethereum         | v6.7.0+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_COIN_ID`                   |          | Explicitly set CoinGecko coin ID.                                                                                                                                                                                                                                                                 | (empty)          | v4.1.4+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_SECONDARY_COIN_ID`         |          | Explicitly set CoinGecko coin ID for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                                     | (empty)          | v6.3.0+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_API_KEY`                   |          | CoinGecko API key.                                                                                                                                                                                                                                                                                | (empty)          | v4.1.4+ | API, Indexer |
| `EXCHANGE_RATES_COINMARKETCAP_API_KEY`               |          | CoinMarketCap API key. Required, if `EXCHANGE_RATES_MARKET_CAP_SOURCE`, `EXCHANGE_RATES_PRICE_SOURCE` is set to `coin_market_cap`.                                                                                                                                                                | (empty)          | v4.1.4+ | API, Indexer |
| `EXCHANGE_RATES_COINMARKETCAP_COIN_ID`               |          | CoinMarketCap coin id.                                                                                                                                                                                                                                                                            | (empty)          | v5.2.1+ | API, Indexer |
| `EXCHANGE_RATES_COINMARKETCAP_SECONDARY_COIN_ID`     |          | CoinMarketCap coin id for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                                                | (empty)          | v6.3.0+ | API, Indexer |
| `EXCHANGE_RATES_DEFILLAMA_COIN_ID`                   |          | DefiLlama coin id.                                                                                                                                                                                                                                                                                | (empty)          | v5.3.0+ | API, Indexer |
| `EXCHANGE_RATES_FETCH_BTC_VALUE`                     |          | if `true` explorer application will fetch btc\_value for token exchange rates. Implemented in [#5671](https://github.com/blockscout/blockscout/pull/5671).                                                                                                                                        | (empty)          | v4.1.5+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_PLATFORM_ID`               |          | [CoinGecko](https://www.coingecko.com/) platform id for which token prices are fetched, see full list in [`/asset_platforms`](https://api.coingecko.com/api/v3/asset_platforms) endpoint. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925).                             | ethereum         | v5.1.2+ | API, Indexer |
| `TOKEN_EXCHANGE_RATE_INTERVAL`                       |          | Interval between batch requests of token prices. Can be decreased in order to fetch prices faster if you have pro rate limit. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925). | 5s               | v5.1.2+ | API, Indexer |
| `TOKEN_EXCHANGE_RATE_REFETCH_INTERVAL`               |          | Interval between refetching token prices, responsible for the relevance of prices. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925).                                            | 1 hour           | v5.1.2+ | API, Indexer |
| `TOKEN_EXCHANGE_RATE_MAX_BATCH_SIZE`                 |          | Batch size of a single token price request. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925).                                                                                                                                                                           | 150              | v5.1.2+ | API, Indexer |
| `DISABLE_TOKEN_EXCHANGE_RATE`                        |          | If `true` disables fetching of token price. Implemented in [#6925](https://github.com/blockscout/blockscout/pull/6925).                                                                                                                                                                           | true             | v5.1.2+ | API, Indexer |
| `EXCHANGE_RATES_CRYPTOCOMPARE_SECONDARY_COIN_SYMBOL` |          | CryptoCompare coin symbol for secondary coin market chart. Implemented in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                                            | (empty)          | v6.3.0+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_BASE_URL`                  |          | If set, overrides the Coingecko base URL. Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679).                                                                                                                                                                             | true             | v6.4.0+ | API, Indexer |
| `EXCHANGE_RATES_COINGECKO_BASE_PRO_URL`              |          | If set, overrides the Coingecko Pro base URL. Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679).                                                                                                                                                                         | true             | v6.4.0+ | API, Indexer |
| `EXCHANGE_RATES_COINMARKETCAP_BASE_URL`              |          | If set, overrides the CoinMarketCap base URL (Free and Pro). Implemented in [#9679](https://github.com/blockscout/blockscout/pull/9679).                                                                                                                                                          | true             | v6.4.0+ | API, Indexer |

### Cache management

| Variable                                                      | Required | Description                                                                                                                                                                                                                                                                                                                                                                  | Default | Version | Need recompile | Application  |
| ------------------------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | -------------- | ------------ |
| `CACHE_TXS_COUNT_PERIOD`                                      |          | Time interval to restart the task, which calculates the total txs count. Starting from release v6.7.0, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                              | 2h      | v4.1.3+ |                | API, Indexer |
| `CACHE_ADDRESS_SUM_PERIOD`                                    |          | Time to live of addresses sum (except burn address) cache. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Starting from release v6.7.0, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. Introduced in [#2862](https://github.com/poanetwork/blockscout/pull/2862). | 1h      | v4.1.3+ |                | API, Indexer |
| `CACHE_TOTAL_GAS_USAGE_PERIOD`                                |          | Interval to restart the task, which calculates the total gas usage. Starting from release v6.7.0, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                   | 2h      | v4.1.3+ |                | API, Indexer |
| `CACHE_PBO_COUNT_PERIOD`                                      |          | Time interval to restart the task, which calculates the total pending\_block\_operations count. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                      | 20m     | v5.2.0+ |                | API, Indexer |
| `CACHE_ADDRESS_TRANSACTIONS_GAS_USAGE_COUNTER_PERIOD`         |          | Interval to restart the task, which calculates gas usage at the address. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                             | 30m     | v4.1.3+ |                | API, Indexer |
| `CACHE_TOKEN_HOLDERS_COUNTER_PERIOD`                          |          | Interval to restart the task, which calculates holders count of the token. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                           | 1h      | v4.1.3+ |                | API, Indexer |
| `CACHE_TOKEN_TRANSFERS_COUNTER_PERIOD`                        |          | Interval to restart the task, which calculates transfers count of the token. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                         | 1h      | v4.1.3+ |                | API, Indexer |
| `CACHE_ADDRESS_WITH_BALANCES_UPDATE_INTERVAL`                 |          | Interval to restart the task, which calculates addresses with balances. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                              | 30m     | v4.1.3+ | ✅              | API, Indexer |
| `TOKEN_METADATA_UPDATE_INTERVAL`                              |          | Interval to restart the task which updates token metadata. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                                           | 48h     | v2.0.1+ |                | API, Indexer |
| `CACHE_AVERAGE_BLOCK_PERIOD`                                  |          | Update of average block period cache. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                                                                | 30m     | v4.1.3+ |                | API, Indexer |
| `CACHE_MARKET_HISTORY_PERIOD`                                 |          | Update of market history cache. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                                                                      | 6h      | v4.1.3+ |                | API, Indexer |
| `CACHE_ADDRESS_TRANSACTIONS_COUNTER_PERIOD`                   |          | Time to live of address' transactions counter. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#3330](https://github.com/poanetwork/blockscout/pull/3330).                                                                                                                                                            | 1h      | v3.4.0+ |                | API, Indexer |
| `CACHE_ADDRESS_TOKENS_USD_SUM_PERIOD`                         |          | Managing of cache invalidation period for the sum of USD value of tokens per tokens' holder address. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                 | 1h      | v3.5.0+ |                | API, Indexer |
| `CACHE_EXCHANGE_RATES_PERIOD`                                 |          | Value which is to tune the time to live of exchange rates. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#5671](https://github.com/blockscout/blockscout/pull/5671).                                                                                                                                               | 10m     | v4.1.5+ | ✅              | API, Indexer |
| `TOKEN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD`                   |          | A threshold to invalidate token balance cache. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                                                       | 1h      | v5.1.2+ |                | API, Indexer |
| `COIN_BALANCE_ON_DEMAND_FETCHER_THRESHOLD`                    |          | A threshold to invalidate coin balance cache. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                                                                                                                                                                        | 1h      | v5.1.2+ |                | API, Indexer |
| `CONTRACT_CODE_ON_DEMAND_FETCHER_THRESHOLD`                   |          | An initial threshold (for exponential backoff) to fetch smart-contract bytecode on-demand. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#9708](https://github.com/blockscout/blockscout/pull/9708).                                                                                                               | 5s      | v6.4.0+ |                | API, Indexer |
| `TOKEN_INSTANCE_METADATA_REFETCH_ON_DEMAND_FETCHER_THRESHOLD` |          | An initial threshold (for exponential backoff) to re-fetch token instance's metadata on-demand. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#10097](https://github.com/blockscout/blockscout/pull/10097).                                                                                                        | 5s      | v6.7.0+ |                | API, Indexer |
| `CACHE_ADDRESS_TOKEN_TRANSFERS_COUNTER_PERIOD`                |          | Interval to restart the task, which calculates the number of token transfers at the address. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#4699](https://github.com/poanetwork/blockscout/pull/4699).                                                                                                             | 1h      | v4.0.0+ |                | API, Indexer |
| `CACHE_BLOCK_COUNT_PERIOD`                                    |          | Time to live of blocks with consensus count cache. Starting from release v6.7.0, if the value is not set, ttl value gradually increases until the default value with growth of the block numbers. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#1876](https://github.com/poanetwork/blockscout/pull/1876).         | 2h      | v4.1.3+ |                | API, Indexer |
| `CACHE_TOTAL_GAS_USAGE_COUNTER_ENABLED`                       |          | if `true`, enables cache for total gas usage counter.                                                                                                                                                                                                                                                                                                                        | `false` | v5.1.3+ | ✅              | API, Indexer |
| `MARKET_HISTORY_FETCH_INTERVAL`                               |          | Interval to update data for the last day in Market History table. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#9197](https://github.com/blockscout/blockscout/pull/9197).                                                                                                                                         | 1h      | v6.1.0+ |                | API, Indexer |
| `CACHE_TRANSACTIONS_24H_STATS_PERIOD`                         |          | Interval to update data for the last 24 hours transactions stats. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                                         | 1h      | v6.3.0+ |                | API, Indexer |
| `CACHE_FRESH_PENDING_TRANSACTIONS_COUNTER_PERIOD`             |          | Interval to update count of pending transactions that appeared less than half an hour ago. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#9483](https://github.com/blockscout/blockscout/pull/9483).                                                                                                                | 5m      | v6.3.0+ |                | API, Indexer |
| `CACHE_OPTIMISM_LAST_OUTPUT_ROOT_SIZE_COUNTER_PERIOD`         |          | Interval to update data for the last output root size counter. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Introduced in [#9532](https://github.com/blockscout/blockscout/pull/9532).                                                                                                                                            | 5m      | v6.3.0+ |                | API, Indexer |

### Gas price oracle management

| Variable                                    | Required | Description                                                                                                                                                                                                                  | Default | Version | Application  |
| ------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ------------ |
| `GAS_PRICE_ORACLE_NUM_OF_BLOCKS`            |          | Gas price oracle: number of blocks to calculate average gas price from                                                                                                                                                       | 200     | v4.1.4+ | API, Indexer |
| `GAS_PRICE_ORACLE_SAFELOW_PERCENTILE`       |          | Gas price oracle: safelow percentile                                                                                                                                                                                         | 35      | v4.1.4+ | API, Indexer |
| `GAS_PRICE_ORACLE_AVERAGE_PERCENTILE`       |          | Gas price oracle: average percentile                                                                                                                                                                                         | 60      | v4.1.4+ | API, Indexer |
| `GAS_PRICE_ORACLE_FAST_PERCENTILE`          |          | Gas price oracle: fast percentile                                                                                                                                                                                            | 90      | v4.1.4+ | API, Indexer |
| `GAS_PRICE_ORACLE_CACHE_PERIOD`             |          | Gas price oracle: period of gas prices update. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format).                                                                                       | 30s     | v4.1.4+ | API, Indexer |
| `GAS_PRICE_ORACLE_SIMPLE_TRANSACTION_GAS`   |          | Gas price oracle: amount of gas for a simple coin transfer. Introduced in [#9044](https://github.com/blockscout/blockscout/pull/9044).                                                                                       | 21000   | v6.0.0+ | API, Indexer |
| `GAS_PRICE_ORACLE_SAFELOW_TIME_COEFFICIENT` |          | Average block time multiplied by this coefficient for safelow gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582). | 5       | v6.3.0+ | API, Indexer |
| `GAS_PRICE_ORACLE_AVERAGE_TIME_COEFFICIENT` |          | Average block time multiplied by this coefficient for average gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582). | 3       | v6.3.0+ | API, Indexer |
| `GAS_PRICE_ORACLE_FAST_TIME_COEFFICIENT`    |          | Average block time multiplied by this coefficient for fast gas price when time from pending transactions is not available. Floats may be used. Introduced in [#9582](https://github.com/blockscout/blockscout/pull/9582).    | 1       | v6.3.0+ | API, Indexer |

### Main page dashboard management

| Variable                            | Required | Description                                                                                                                                                                                                   | Default | Version | Application |
| ----------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `GAS_PRICE`                         |          | Gas price in Gwei. If the variable is present, gas price displays on the main page.                                                                                                                           | (empty) | v3.3.2+ | API         |
| `TXS_STATS_ENABLED`                 |          | Disables or enables txs per day stats gathering.                                                                                                                                                              | true    | v5.1.3+ | API         |
| `SHOW_PRICE_CHART`                  |          | Disables or enables price and market cap of coin charts on the main page.                                                                                                                                     | false   | v3.1.2+ | API         |
| `SHOW_PRICE_CHART_LEGEND`           |          | Allows to show price and market cap values under the chart even if price chart is not enabled via `SHOW_PRICE_CHART` env variable.                                                                            | false   | v5.1.4+ | API         |
| `SHOW_TXS_CHART`                    |          | Disables or enables txs count per day chart on the main page.                                                                                                                                                 | true    | v3.1.2+ | API         |
| `TXS_HISTORIAN_INIT_LAG`            |          | The initial delay in txs count history fetching in order to display txs count per day history chart on the main page. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). | 0       | v3.1.2+ | API         |
| `TXS_STATS_DAYS_TO_COMPILE_AT_INIT` |          | Number of days for fetching of history of txs count per day in order to display it in txs count per day history chart on the main page.                                                                       | 40      | v3.1.2+ | API         |

### Header management

| Variable             | Required | Description                                                                                                                                                                                                                                                                                                    | Default                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | Version | Application |
| -------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ----------- |
| `LOGO`               |          | Environment variable for the header logo image location. The logo files names for different chains can be found [here](https://github.com/poanetwork/blockscout/tree/master/apps/block_scout_web/assets/static/images).                                                                                        | /images/blockscout\_logo.svg                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | all     | API         |
| `SHOW_TESTNET_LABEL` |          | Enables testnet label right after logo in the navigation panel. Implemented in [#5732](https://github.com/blockscout/blockscout/pull/5732)                                                                                                                                                                     | (empty)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | v4.1.6+ | API         |
| `TESTNET_LABEL_TEXT` |          | The text inside the test label. Implemented in [#5732](https://github.com/blockscout/blockscout/pull/5732)                                                                                                                                                                                                     | Testnet                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | v4.1.6+ | API         |
| `SUPPORTED_CHAINS`   |          | An array of supported chains that display in the footer and in the chains dropdown. This var was introduced in this PR [#1900](https://github.com/poanetwork/blockscout/pull/1900) and looks like an array of JSON objects.                                                                                    | \[ \{ title: "POA", url: "[https://blockscout.com/poa/core](https://blockscout.com/poa/core)" }, \{ title: "Sokol", url: "[https://blockscout.com/poa/sokol](https://blockscout.com/poa/sokol)", test\_net?: true }, \{ title: "Gnosis Chain", url: "[https://gnosis.blockscout.com/](https://gnosis.blockscout.com/)" }, \{ title: "Ethereum Classic", url: "[https://etc.blockscout.com](https://etc.blockscout.com)", other?: true }, \{ title: "RSK", url: "[https://rootstock.blockscout.com](https://rootstock.blockscout.com)", other?: true } ] | v2.0.0+ | API         |
| `APPS_MENU`          |          | true/false. If true, the Apps navigation menu item appears.                                                                                                                                                                                                                                                    | false                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | v3.3.1+ | API         |
| `APPS`               |          | An array of embedded/external apps to display in Apps menu item. This var was introduced in this PR [#3184](https://github.com/poanetwork/blockscout/pull/3184) and looks like an array of JSON objects. An example of embedded link is described here [#](https://github.com/blockscout/blockscout/pull/6397) | (empty)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | v5.0.0+ | API         |

### Footer management

| Variable                         | Required | Description                                                                                                                                                                                                             | Default                                                                              | Version | Application |
| -------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------ | ------- | ----------- |
| `FOOTER_LOGO`                    |          | Environment variable for the footer logo image location. The logo files names for different chains can be found [here](https://github.com/poanetwork/blockscout/tree/master/apps/block_scout_web/assets/static/images). | /images/blockscout\_logo.svg                                                         |         | API         |
| `RELEASE_LINK`                   |          | The link to Blockscout release notes in the footer.                                                                                                                                                                     | https: //github.com/poanetwork/ blockscout/releases/ tag/\$\{BLOCKSCOUT\_VERSION}    | v1.3.5+ | API         |
| `BLOCKSCOUT_VERSION`             |          | Added to the footer to signify the current BlockScout version.                                                                                                                                                          | (empty)                                                                              | v1.3.4+ | API         |
| `FOOTER_CHAT_LINK`               |          | Link in Chat menu item in the footer. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719).                                                                                                       | [https://discord.gg/3CtNAqVMRV](https://discord.gg/3CtNAqVMRV)                       | v4.1.6+ | API         |
| `FOOTER_FORUM_LINK_ENABLED`      |          | Enable forum menu item in the footer.                                                                                                                                                                                   | false                                                                                | v5.1.3+ | API         |
| `FOOTER_FORUM_LINK`              |          | Link in Forum menu item in the footer. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719)                                                                                                       | [https://forum.poa.network/c/blockscout](https://forum.poa.network/c/blockscout)     | v4.1.6+ | API         |
| `FOOTER_TELEGRAM_LINK_ENABLED`   |          | Enable Telegram menu item in the footer. Implemented in [#7345](https://github.com/blockscout/blockscout/pull/7345).                                                                                                    | false                                                                                | v5.1.4+ | API         |
| `FOOTER_TELEGRAM_LINK`           |          | Link in Telegram menu item in the footer. Implemented in [#7345](https://github.com/blockscout/blockscout/pull/7345).                                                                                                   |                                                                                      | v5.1.4+ | API         |
| `FOOTER_GITHUB_LINK`             |          | Github repository. Implemented in [#5719](https://github.com/blockscout/blockscout/pull/5719).                                                                                                                          | [https://github.com/blockscout/blockscout](https://github.com/blockscout/blockscout) | v4.1.6+ | API         |
| `FOOTER_LINK_TO_OTHER_EXPLORERS` |          | true/false. If true, links to other explorers are added in the footer.                                                                                                                                                  | (empty)                                                                              | v5.1.3+ | API         |
| `FOOTER_OTHER_EXPLORERS`         |          | The list of alternative explorers.                                                                                                                                                                                      | (empty)                                                                              | v5.1.3+ | API         |

### Contract management

| Variable                                               | Required | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | Default                                                                                                                       | Version | Application  |
| ------------------------------------------------------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------- | ------- | ------------ |
| `CONTRACT_VERIFICATION_ALLOWED_SOLIDITY_EVM_VERSIONS`  |          | the comma-separated list of allowed EVM versions for Solidity contract verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964), updated in [#7614](https://github.com/blockscout/blockscout/pull/7614).                                                                                                                                                                                                                                                   | "homestead,tangerineWhistle,spuriousDragon,byzantium,constantinople,petersburg,istanbul,berlin,london,paris,shanghai,default" | v5.2.0+ | API          |
| `CONTRACT_VERIFICATION_ALLOWED_VYPER_EVM_VERSIONS`     |          | the comma-separated list of allowed EVM versions for Vyper contract verification. This var was introduced in [#7614](https://github.com/blockscout/blockscout/pull/7614).                                                                                                                                                                                                                                                                                                                              | "byzantium,constantinople,petersburg,istanbul,berlin,paris,shanghai,default"                                                  | v5.2.0+ | API          |
| `CONTRACT_VERIFICATION_MAX_LIBRARIES`                  |          | Max amount of libraries to consider in smart-contract verification from flat/multi-part file(s). Implemented in [#6204](https://github.com/blockscout/blockscout/pull/6204).                                                                                                                                                                                                                                                                                                                           | (empty)                                                                                                                       | v5.0.0+ | API          |
| `CONTRACT_MAX_STRING_LENGTH_WITHOUT_TRIMMING`          |          | Hide long contract method data. For more details: [#4667](https://github.com/blockscout/blockscout/pull/4667)                                                                                                                                                                                                                                                                                                                                                                                          | 2040                                                                                                                          | v4.0.0+ | API          |
| `CONTRACT_DISABLE_INTERACTION`                         |          | If `true`, contract interactions via "Write contract" or "Write proxy contract" tabs are disabled. Introduced in [#7088](https://github.com/blockscout/blockscout/pull/7088).                                                                                                                                                                                                                                                                                                                          | (empty)                                                                                                                       | v5.1.2+ | API          |
| `CONTRACT_PROXY_IMPLEMENTATION_TTL_VIA_AVG_BLOCK_TIME` |          | If `false`, proxy contract implementation will be re-fetched immediately once someone opend proxy page bypassing average block time calculation. Implemented in [#9155](https://github.com/blockscout/blockscout/pull/9155).                                                                                                                                                                                                                                                                           | true                                                                                                                          | v6.1.0+ | API          |
| `CONTRACT_AUDIT_REPORTS_AIRTABLE_URL`                  |          | URL of AirTable to store audit reports from users. Implemented in [#9120](https://github.com/blockscout/blockscout/pull/9120)                                                                                                                                                                                                                                                                                                                                                                          | (empty)                                                                                                                       | v6.1.0+ | API          |
| `CONTRACT_AUDIT_REPORTS_AIRTABLE_API_KEY`              |          | Access token for `CONTRACT_AUDIT_REPORTS_AIRTABLE_URL`. Implemented in [#9120](https://github.com/blockscout/blockscout/pull/9120)                                                                                                                                                                                                                                                                                                                                                                     | (empty)                                                                                                                       | v6.1.0+ | API          |
| `CONTRACT_CERTIFIED_LIST`                              |          | Comma-separated list of smart-contract addresses hashes, to which "certified" flag should be applied. Implemented in [#9910](https://github.com/blockscout/blockscout/pull/9910)                                                                                                                                                                                                                                                                                                                       | (empty)                                                                                                                       | v6.5.0+ | API          |
| `WHITELISTED_WETH_CONTRACTS`                           |          | Comma-separated list of smart-contract addresses hashes of wrapped tokens of chain's native coin, which deposit and withdrawal events you'd like to index. Attention ⚠️: all transfers of non-whitelisted tokens created from deposit/withdrawal events will be deleted from the DB. If variable is set, and empty list is provided, all transfers of created from deposit/withdrawal events will be deleted from the DB. Implemented in [#10134](https://github.com/blockscout/blockscout/pull/10134) | (empty)                                                                                                                       | v6.7.0+ | API, Indexer |
| `WETH_TOKEN_TRANSFERS_FILTERING_ENABLED`               |          | Toggle for WETH token transfers filtering which was introduced in [#10134](https://github.com/blockscout/blockscout/pull/10134). Implemented in [#10208](https://github.com/blockscout/blockscout/pull/10208)                                                                                                                                                                                                                                                                                          | false                                                                                                                         | v6.7.0+ | API, Indexer |

### Bridged tokens

| Variable                                  | Required | Description                                                                                                                 | Default | Version | Need recompile | Application  |
| ----------------------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | -------------- | ------------ |
| `BRIDGED_TOKENS_ENABLED`                  |          | Variable to enabled bridged tokens functionality. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169) | (empty) | v6.1.0+ | ✅              | API, Indexer |
| `BRIDGED_TOKENS_ETH_OMNI_BRIDGE_MEDIATOR` |          | OMNI bridge mediator for ETH tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)              | (empty) | v6.1.0+ |                | API, Indexer |
| `BRIDGED_TOKENS_BSC_OMNI_BRIDGE_MEDIATOR` |          | OMNI bridge mediator for BSC tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)              | (empty) | v6.1.0+ |                | API, Indexer |
| `BRIDGED_TOKENS_POA_OMNI_BRIDGE_MEDIATOR` |          | OMNI bridge mediator for POA tokens. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)              | (empty) | v6.1.0+ |                | API, Indexer |
| `BRIDGED_TOKENS_AMB_BRIDGE_MEDIATORS`     |          | AMB bridge mediator. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)                              | (empty) | v6.1.0+ |                | API, Indexer |
| `BRIDGED_TOKENS_FOREIGN_JSON_RPC`         |          | Ethereum mainnet JSON RPC. Introduced in [#9169](https://github.com/blockscout/blockscout/pull/9169)                        | (empty) | v6.1.0+ |                | API, Indexer |

### Misc UI management

| Variable                            | Required | Description                                                                                                                                                      | Default | Version | Need recompile | Application |
| ----------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | -------------- | ----------- |
| `SHOW_ADDRESS_MARKETCAP_PERCENTAGE` |          | Configures market cap percentage column on the top accounts page.                                                                                                | `true`  | v2.1.1+ |                | API         |
| `SHOW_MAINTENANCE_ALERT`            |          | Disables/enables announcement at the top of the explorer.                                                                                                        | false   | v3.6.0+ |                | API         |
| `MAINTENANCE_ALERT_MESSAGE`         |          | Message text of the announcement at the top of the explorer.                                                                                                     | (empty) | v3.6.0+ |                | API         |
| `HIDE_BLOCK_MINER`                  |          | Hides miner/validator/sequencer on block page and tiles if the value is \`true\` Implemented in [#4611](https://github.com/blockscout/blockscout/pull/4611)      | (empty) | v4.0.0+ |                | API         |
| `DISPLAY_TOKEN_ICONS`               |          | Displays token icons from TrustWallet assets repository if `true`. Implemented in [#4596](https://github.com/blockscout/blockscout/pull/4596)                    | (empty) | v4.0.0+ |                | API         |
| `UNCLES_IN_AVERAGE_BLOCK_TIME`      |          | Include or exclude non-consensus blocks in avg block time calculation. Exclude if `false`.                                                                       | false   | v2.0.1+ |                | API         |
| `COIN_BALANCE_HISTORY_DAYS`         |          | Number of days to consider at coin balance history chart.                                                                                                        | 10      | v3.1.3+ |                | API         |
| `ADMIN_PANEL_ENABLED`               |          | if `true` admin/\* routes are available. Implemented in [#5208](https://github.com/blockscout/blockscout/pull/5208)                                              | (empty) | v4.1.2+ | ✅              | API         |
| `DISABLE_ADD_TO_MM_BUTTON`          |          | If `true`, "Add chain to MM" button doesn't appear. Implemented in [#6843](https://github.com/blockscout/blockscout/pull/6843)                                   | (empty) | v5.1.0+ |                | API         |
| `PERMANENT_DARK_MODE_ENABLED`       |          | If `true`, permanent dark mode is enabled. Dark mode switcher is hidden in this case. Implemented in [#6763](https://github.com/blockscout/blockscout/pull/6763) | (empty) | v5.1.0+ |                | API         |
| `PERMANENT_LIGHT_MODE_ENABLED`      |          | If `true`, permanent light mode is enabled. Dark mode switcher is hidden. Implemented in [#6838](https://github.com/blockscout/blockscout/pull/6838)             | (empty) | v5.1.0+ |                | API         |

### CSV export

reCAPTCHA v2 and v3 keys for CSV export page. Do not use both v2/v3 keys. Only one version of reCAPTCHA should be used.

| Variable                   | Required | Description                                                                                                                             | Default | Version | Application |
| -------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `RE_CAPTCHA_SECRET_KEY`    |          | Google reCAPTCHA v2 secret key. Used by advanced CSV export. Implemented in [#4747](https://github.com/blockscout/blockscout/pull/4747) | (empty) | v4.0.0+ | API         |
| `RE_CAPTCHA_CLIENT_KEY`    |          | Google reCAPTCHA v2 client key. Used by advanced CSV export. Implemented in [#4747](https://github.com/blockscout/blockscout/pull/4747) | (empty) | v4.0.0+ | API         |
| `RE_CAPTCHA_V3_SECRET_KEY` |          | Google reCAPTCHA v3 secret key. Used by advanced CSV export. Implemented in [#7273](https://github.com/blockscout/blockscout/pull/7273) | (empty) | v5.1.4+ | API         |
| `RE_CAPTCHA_V3_CLIENT_KEY` |          | Google reCAPTCHA v3 client key. Used by advanced CSV export. Implemented in [#7273](https://github.com/blockscout/blockscout/pull/7273) | (empty) | v5.1.4+ | API         |
| `RE_CAPTCHA_DISABLED`      |          | Disable reCAPTCHA. Implemented in [#7416](https://github.com/blockscout/blockscout/pull/7416)                                           | false   | v5.1.5+ | API         |

### API rate limit management

| Variable                                    | Required | Description                                                                                                                                                                                                                                           | Default    | Version | Need recompile | Application |
| ------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------- | ------- | -------------- | ----------- |
| `API_RATE_LIMIT`                            |          | A global API rate limit: number or requests per second for all users. Implemented in [#5030](https://github.com/blockscout/blockscout/pull/5030)                                                                                                      | 50 req/sec | v4.1.1+ |                | API         |
| `API_RATE_LIMIT_BY_KEY`                     |          | A dedicated API rate limit per key for every type of API key (static or generated from Account module). Implemented in [#5080](https://github.com/blockscout/blockscout/pull/5080)                                                                    | 10 req/sec | v4.1.1+ |                | API         |
| `API_RATE_LIMIT_WHITELISTED_IPS`            |          | Comma-separated whitelisted IPs list with dedicated rate limit. Implemented in [#5090](https://github.com/blockscout/blockscout/pull/5090)                                                                                                            | (empty)    | v4.1.1+ |                | API         |
| `API_RATE_LIMIT_STATIC_API_KEY`             |          | Static API key with dedicated API rate limit. Implemented in [#5080](https://github.com/blockscout/blockscout/pull/5080)                                                                                                                              | (empty)    | v4.1.1+ |                | API         |
| `API_RATE_LIMIT_DISABLED`                   |          | If `true`, any type of rate limit is ignored. Implemented in [#6908](https://github.com/blockscout/blockscout/pull/6908)                                                                                                                              | (empty)    | v5.1.0+ |                | API         |
| `API_RATE_LIMIT_IS_BLOCKSCOUT_BEHIND_PROXY` |          | If `true`, then IP address of a client will be derived from proxy's headers (like `X-Forwarded-For`) using [RemoteIp](https://hexdocs.pm/remote_ip/RemoteIp.html) library. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148) | false      | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_BY_WHITELISTED_IP`          |          | A dedicated API rate limit for whitelisted IPs. Implemented in [#5090](https://github.com/blockscout/blockscout/pull/5090)                                                                                                                            | 50 req/sec | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_BY_IP`                      |          | Global rate limit for an IP address for API v2 requests sent from UI. [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                     | 3000       | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_HAMMER_REDIS_URL`           |          | Redis DB URL for Hammer rate limit library. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                                | (empty)    | v5.1.3+ | ✅              | API         |
| `API_RATE_LIMIT_UI_V2_WITH_TOKEN`           |          | Rate limit after submitting correct CAPTCHA. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                                                                               | 5          | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_TIME_INTERVAL`              |          | Time interval of rate limit. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                       | 1s         | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_BY_IP_TIME_INTERVAL`        |          | Time interval of rate limit set by `API_RATE_LIMIT_BY_IP`. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                         | 5m         | v5.1.3+ |                | API         |
| `API_RATE_LIMIT_UI_V2_TOKEN_TTL_IN_SECONDS` |          | TTL for token issued after submitting correct CAPTCHA for an API v2 requests from UI. In seconds. Implemented in [#7148](https://github.com/blockscout/blockscout/pull/7148)                                                                          | 18000      | v5.1.3+ |                | API         |
| `ETH_JSON_RPC_MAX_BATCH_SIZE`               |          | Max batch size for Eth JSON RPC requests. Implemented in [#9409](https://github.com/blockscout/blockscout/pull/9409)                                                                                                                                  | 5          | v6.3.0+ |                | API         |

### GraphQL API management

| Variable                                     | Required | Description                                                                                                                                                                                                                                                   | Default                                                            | Version | Need recompile | Application |
| -------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------ | ------- | -------------- | ----------- |
| `API_GRAPHQL_ENABLED`                        |          | Enabling/disabling of GraphQL API. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751)                                                                                                                                                 | true                                                               | v6.4.0+ |                | API         |
| `API_GRAPHQL_MAX_COMPLEXITY`                 |          | Query/schema [max\_complexity](https://hexdocs.pm/absinthe/complexity-analysis.html#complexity-analysis) of GraphQL API. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751)                                                           | 215                                                                | v6.4.0+ | ✅              | API         |
| `API_GRAPHQL_TOKEN_LIMIT`                    |          | Query [token\_limit](https://hexdocs.pm/absinthe/complexity-analysis.html#token-limits) of Absinthe. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751)                                                                               | 1000                                                               | v6.4.0+ | ✅              | API         |
| `API_GRAPHQL_DEFAULT_TRANSACTION_HASH`       |          | Default transaction hash in a sample query to GraphiQL. Implemented in [#9751](https://github.com/blockscout/blockscout/pull/9751).                                                                                                                           | 0x69e3923eef50eada197c3336d546936d0c994211492c9f947a24c02827568f9f | v6.4.0+ | ✅              | API         |
| `API_GRAPHQL_RATE_LIMIT`                     |          | A global GraphQL API rate limit: number or requests per second for all users. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                      | 10 req/sec                                                         | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_BY_KEY`              |          | A dedicated GraphQL API rate limit per static key. If this limit is less than stated in API plan, then `API_GRAPHQL_RATE_LIMIT_BY_KEY` used for key generated from Account module. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771) | 5 req/sec                                                          | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_STATIC_API_KEY`      |          | Static GraphQL API key with dedicated GraphQL API rate limit. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                      | (empty)                                                            | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_DISABLED`            |          | If `true`, any type of rate limit is ignored. Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                      | (empty)                                                            | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_BY_IP`               |          | Global rate limit for an IP address for GraphQL API requests. [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                                                                                                     | 500                                                                | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_TIME_INTERVAL`       |          | Time interval of rate limit. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                                                               | 1s                                                                 | v6.4.0+ |                | API         |
| `API_GRAPHQL_RATE_LIMIT_BY_IP_TIME_INTERVAL` |          | Time interval of rate limit set by `API_GRAPHQL_RATE_LIMIT_BY_IP`. [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format). Implemented in [#9771](https://github.com/blockscout/blockscout/pull/9771)                         | 5m                                                                 | v6.4.0+ |                | API         |

### Specific smart-contracts

| Variable                | Required | Description                                                                                                                                                                                              | Default                                      | Version | Application  |
| ----------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- | ------- | ------------ |
| `METADATA_CONTRACT`     |          | This environment variable is specifically used by POA Network to obtain Validators information to display in the UI.                                                                                     | (empty)                                      | all     | API, Indexer |
| `VALIDATORS_CONTRACT`   |          | This environment variable is specifically used by POA Network to obtain the list of current validators.                                                                                                  | (empty)                                      | all     | API, Indexer |
| `KEYS_MANAGER_CONTRACT` |          | This environment variable is specifically used by POA Network to set KeysManager proxy contract in order to obtain payout key by mining key. This needs to identify distributed reward to the validator. | (empty)                                      | v3.1.2+ | API, Indexer |
| `REWARDS_CONTRACT`      |          | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA`                                                                                                        | `0xeca443e8e1ab29971a45a9c57a6a9875701698a5` | v2.0.4+ | API, Indexer |
| `TOKEN_BRIDGE_CONTRACT` |          | Token bridge proxy contract. For \`TokenBridge\` supply module.                                                                                                                                          | `0x7301CFA0e1756B71869E93d4e4Dca5c7d0eb0AA6` | v1.3.2+ | API, Indexer |

### Account-related ENV variables

| Variable                                            | Required | Description                                                                                                                                                                                                  | Default                   | Version | Application |
| --------------------------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------- | ------- | ----------- |
| `ACCOUNT_ENABLED`                                   |          | Turn on/off account functionality. If value is`true`, account functionality is enabled.                                                                                                                      | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_DATABASE_URL`                              |          | Account DB connection string                                                                                                                                                                                 | value from `DATABASE_URL` | 5.0.0   | API         |
| `ACCOUNT_REDIS_URL`                                 |          | Account Redis connection string (for session storing configuration)                                                                                                                                          | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_POOL_SIZE`                                 |          | Account DB `pool_size`                                                                                                                                                                                       | 50                        | 5.0.0   | API         |
| `ACCOUNT_AUTH0_DOMAIN`                              |          | Domain for [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                                 | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_AUTH0_CLIENT_ID`                           |          | Auth0 client ID [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                            | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_AUTH0_CLIENT_SECRET`                       |          | Auth0 client secret [Ueberauth Auth0](https://hexdocs.pm/ueberauth_auth0/readme.html)                                                                                                                        | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_PUBLIC_TAGS_AIRTABLE_URL`                  |          | Airtable URL for public tag requests functionality                                                                                                                                                           | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_PUBLIC_TAGS_AIRTABLE_API_KEY`              |          | Airtable API key for public tag requests functionality                                                                                                                                                       | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_SENDGRID_API_KEY`                          |          | Sendgrid API key for watchlist notifications functionality                                                                                                                                                   | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_SENDGRID_SENDER`                           |          | Sendgrid sender email for watchlist notifications functionality                                                                                                                                              | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_SENDGRID_TEMPLATE`                         |          | Sendgrid email template for watchlist notifications functionality                                                                                                                                            | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_CLOAK_KEY`                                 |          | Account DB encryption key. [Instruction how to generate](https://hexdocs.pm/cloak_ecto/generate_keys.html#content)                                                                                           | (empty)                   | 5.0.0   | API         |
| `ACCOUNT_VERIFICATION_EMAIL_RESEND_INTERVAL`        |          | Time before resending confirmation email. Implemented in [#7298](https://github.com/blockscout/blockscout/pull/7298). [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format) | `5m`                      | v5.1.5+ | API         |
| `ACCOUNT_PRIVATE_TAGS_LIMIT`                        |          | Limit for address & transaction tags. Implemented in [#8528](https://github.com/blockscout/blockscout/pull/8528).                                                                                            | 2000                      | v5.3.1+ | API         |
| `ACCOUNT_WATCHLIST_ADDRESSES_LIMIT`                 |          | Limit for watch list addresses. Implemented in [#8528](https://github.com/blockscout/blockscout/pull/8528).                                                                                                  | 15                        | v5.3.1+ | API         |
| `ACCOUNT_WATCHLIST_NOTIFICATIONS_LIMIT_FOR_30_DAYS` |          | Per account limit for watch list notifications sent for the last 30 days. Implemented in [#8966](https://github.com/blockscout/blockscout/pull/8966).                                                        | 1000                      | v5.3.3+ | API         |

### Integrations

#### Smart-contract verifier / Eth Bytecode DB

| Variable                                                | Required | Description                                                                                                                                                                                                                                                                               | Default                                                                                              | Version | Application |
| ------------------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------- | ------- | ----------- |
| `MICROSERVICE_SC_VERIFIER_ENABLED`                      |          | If `true`, integration with [Rust smart-contract verifier](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier) is enabled. `true` is the default value starting from version 6.4.0. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860) | true                                                                                                 | v5.1.3+ | API         |
| `MICROSERVICE_SC_VERIFIER_URL`                          |          | URL of Rust smart-contract verifier. Implemented in [#5860](https://github.com/blockscout/blockscout/pull/5860)                                                                                                                                                                           | [https://eth-bytecode-db.services.blockscout.com/](https://eth-bytecode-db.services.blockscout.com/) | v5.1.3+ | API         |
| `MICROSERVICE_ETH_BYTECODE_DB_INTERVAL_BETWEEN_LOOKUPS` |          | Minimal time after unsuccessful check of smart contract's sources in Eth Bytecode DB. Implemented in [#7187](https://github.com/blockscout/blockscout/pull/7187). [Time format](/setup/env-variables/deprecated-env-variables/env-variables#time-format)                                  | 10m                                                                                                  | v5.1.3+ | API         |
| `MICROSERVICE_SC_VERIFIER_TYPE`                         |          | Type of smart contract microservice could be either `eth_bytecode_db` or `sc_verifier`. Implemented in [#7187](https://github.com/blockscout/blockscout/pull/7187)                                                                                                                        | `eth_bytecode_db`                                                                                    | v5.1.3+ | API         |
| `MICROSERVICE_ETH_BYTECODE_DB_MAX_LOOKUPS_CONCURRENCY`  |          | Maximum amount of concurrent requests for fetching smart contract's sources in Eth Bytecode DB. Implemented in [#8472](https://github.com/blockscout/blockscout/pull/8472)                                                                                                                | 10                                                                                                   | v5.3.0+ | API         |
| `MICROSERVICE_SC_VERIFIER_API_KEY`                      |          | API key for verification that metadata sent to verifier microservice from a trusted source. Implemented in [#8750](https://github.com/blockscout/blockscout/pull/8750)                                                                                                                    | (empty)                                                                                              | v5.3.2+ | API         |

#### Sol2Uml

| Variable                                 | Required | Description                                                                                                                                                                                                    | Default | Version | Application |
| ---------------------------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `MICROSERVICE_VISUALIZE_SOL2UML_ENABLED` |          | If `true`, integration with [Rust sol2uml visualizer](https://github.com/blockscout/blockscout-rs/tree/main/visualizer) is enabled. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401) | (empty) | v5.1.3+ | API         |
| `MICROSERVICE_VISUALIZE_SOL2UML_URL`     |          | URL of Rust visualizer. Implemented in [#6401](https://github.com/blockscout/blockscout/pull/6401)                                                                                                             | (empty) | v5.1.3+ | API         |

#### Sig-provider

| Variable                            | Required | Description                                                                                                                                                                                                        | Default | Version | Application |
| ----------------------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------- | ------- | ----------- |
| `MICROSERVICE_SIG_PROVIDER_ENABLED` |          | If `true`, integration with [Rust sig-provider service](https://github.com/blockscout/blockscout-rs/tree/main/sig-provider) is enabled. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541) | (empty) | v5.1.3+ | API         |
| `MICROSERVICE_SIG_PROVIDER_URL`     |          | URL of Rust sig-provider service. Implemented in [#6541](https://github.com/blockscout/blockscout/pull/6541)                                                                                                       | (empty) | v5.1.3+ | API         |

#### Blockscout ENS

| Variable                    | Required | Description                                                                                                                                                                                                       | Default | Version | Application |
| --------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `MICROSERVICE_BENS_ENABLED` |          | If `true`, integration with [Blockscout ENS service](https://github.com/blockscout/blockscout-rs/tree/main/blockscout-ens) is enabled. Implemented in [#8972](https://github.com/blockscout/blockscout/pull/8972) | (empty) | v5.4.0+ | API         |
| `MICROSERVICE_BENS_URL`     |          | URL of Blockscout ENS service. Implemented in [#8972](https://github.com/blockscout/blockscout/pull/8972)                                                                                                         | (empty) | v5.4.0+ | API         |

#### Blockscout Account Abstraction

| Variable                                   | Required | Description                                                                                                                                                                                                                         | Default | Version | Application |
| ------------------------------------------ | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `MICROSERVICE_ACCOUNT_ABSTRACTION_ENABLED` |          | If `true`, integration with [Blockscout Account Abstraction service](https://github.com/blockscout/blockscout-rs/tree/main/user-ops-indexer) is enabled. Implemented in [#9145](https://github.com/blockscout/blockscout/pull/9145) | (empty) | v6.1.0+ | API         |
| `MICROSERVICE_ACCOUNT_ABSTRACTION_URL`     |          | URL of Blockscout ENS service. Implemented in [#9145](https://github.com/blockscout/blockscout/pull/9145)                                                                                                                           | (empty) | v6.1.0+ | API         |

#### Tx Interpreter (Summary) Service

| Variable                                          | Required | Description                                                                                                                               | Default | Version | Application |
| ------------------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `MICROSERVICE_TRANSACTION_INTERPRETATION_ENABLED` |          | If `true`, integration with Tx Interpreter Service is enabled. Implemented in [#8957](https://github.com/blockscout/blockscout/pull/8957) | (empty) | v5.4.0+ | API         |
| `MICROSERVICE_TRANSACTION_INTERPRETATION_URL`     |          | URL of Tx Interpreter Service. Implemented in [#8957](https://github.com/blockscout/blockscout/pull/8957)                                 | (empty) | v5.4.0+ | API         |

#### Metadata Service

| Variable                        | Required | Description                                                                                                                         | Default | Version | Application |
| ------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `MICROSERVICE_METADATA_ENABLED` |          | If `true`, integration with Metadata Service is enabled. Implemented in [#9706](https://github.com/blockscout/blockscout/pull/9706) | (empty) | v6.4.0+ | API         |
| `MICROSERVICE_METADATA_URL`     |          | URL of Metadata Service. Implemented in [#9706](https://github.com/blockscout/blockscout/pull/9706)                                 | (empty) | v6.4.0+ | API         |

#### Sourcify

| Variable                       | Required | Description                                                     | Default                                                                                                                                                                                                | Version | Application |
| ------------------------------ | -------- | --------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------- | ----------- |
| `SOURCIFY_INTEGRATION_ENABLED` |          | Enables or disables verification of contracts through Sourcify. | false                                                                                                                                                                                                  | v5.1.3+ | API         |
| `SOURCIFY_SERVER_URL`          |          | URL to Sourcify backend.                                        | [https://sourcify.dev/server](https://sourcify.dev/server)                                                                                                                                             | v3.7.0+ | API         |
| `SOURCIFY_REPO_URL`            |          | URL to Sourcify repository with fully verified contracts.       | [https://repo.sourcify.dev/contracts/](https://repo.sourcify.dev/contracts/)\*<br />\*before 3.7.1 [https://repo.sourcify.dev/contracts/full\_match/](https://repo.sourcify.dev/contracts/full_match/) | v3.7.0+ | API         |

#### Tenderly

| Variable              | Required | Description                                                                                                                                                                                                                                                                                                             | Default | Version | Application |
| --------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `SHOW_TENDERLY_LINK`  |          | if `true`, "Open in Tenderly" button is displayed on the transaction page. Implemented in [#4656](https://github.com/blockscout/blockscout/pull/4656)                                                                                                                                                                   | (empty) | v4.0.0+ | API         |
| `TENDERLY_CHAIN_PATH` |          | Chain path to the transaction in Tenderly. For instance, for transactions in xDai, Tenderly link looks like this [https://dashboard.tenderly.co/tx/xdai/0x](https://dashboard.tenderly.co/tx/xdai/0x)..., then `TENDERLY_CHAIN_PATH =/xdai.` Implemented in [#4656](https://github.com/blockscout/blockscout/pull/4656) | (empty) | v4.0.0+ | API         |

#### Datadog

| Variable       | Required | Description                                                                                     | Default | Version | Application |
| -------------- | -------- | ----------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `DATADOG_HOST` |          | Host configuration setting for [Datadog integration](https://docs.datadoghq.com/integrations/). | (empty) | all     | API         |
| `DATADOG_PORT` |          | Port configuration setting for [Datadog integration](https://docs.datadoghq.com/integrations/). | (empty} | all     | API         |

#### Spandex

| Variable                 | Required | Description                                                                              | Default | Version | Application |
| ------------------------ | -------- | ---------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `SPANDEX_BATCH_SIZE`     |          | [Spandex](https://github.com/spandex-project/spandex) and Datadog configuration setting. | (empty) | all     | API         |
| `SPANDEX_SYNC_THRESHOLD` |          | [Spandex](https://github.com/spandex-project/spandex) and Datadog configuration setting. | (empty) | all     | API         |

#### Analytics

| Variable            | Required | Description                                                                                                                              | Default | Version | Need recompile | Application |
| ------------------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | -------------- | ----------- |
| `MIXPANEL_TOKEN`    |          | [Mixpanel](https://mixpanel.com/) project token.                                                                                         | (empty) | v5.0.0+ | ✅              | API         |
| `MIXPANEL_URL`      |          | Url to use Mixpanel with proxy ([Collection via Proxy](https://developer.mixpanel.com/docs/collection-via-a-proxy)).                     | (empty) | v5.0.0+ | ✅              | API         |
| `AMPLITUDE_API_KEY` |          | [Amplitude](https://amplitude.com/) API key.                                                                                             | (empty) | v5.0.0+ | ✅              | API         |
| `AMPLITUDE_URL`     |          | Url to use Amplitude with proxy ([Use Domain Proxy to Relay Events](https://www.docs.developers.amplitude.com/analytics/domain-proxy/)). | (empty) | v5.0.0+ | ✅              | API         |

#### Solidityscan

| Variable                 | Required | Description                                                                                                                                                                                                                                                             | Default | Version | Application |
| ------------------------ | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ----------- |
| `SOLIDITYSCAN_CHAIN_ID`  |          | [Solidityscan](https://apidoc.solidityscan.com/solidityscan-security-api/solidityscan-other-apis/quickscan-api-v1) Internal chain id in Solidityscan. It may not match with actual chain ID. Implemented in [#8908](https://github.com/blockscout/blockscout/pull/8908) | (empty) | v5.3.3+ | API         |
| `SOLIDITYSCAN_API_TOKEN` |          | [Solidityscan](https://apidoc.solidityscan.com/solidityscan-security-api/solidityscan-other-apis/quickscan-api-v1) API token for usage of Solidityscan API.                                                                                                             | (empty) | v5.3.3+ | API         |

#### Noves.fi

| Variable                | Required | Description                                                                                                                                            | Default                                                    | Version | Application |
| ----------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------- | ------- | ----------- |
| `NOVES_FI_BASE_API_URL` |          | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) base URL. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056).   | [https://blockscout.noves.fi](https://blockscout.noves.fi) | v6.1.0+ | API         |
| `NOVES_FI_CHAIN_NAME`   |          | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) chain name. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056). | (empty)                                                    | v6.1.0+ | API         |
| `NOVES_FI_API_TOKEN`    |          | [Noves.fi API](https://blockscout.noves.fi/swagger/index.html) token. Implemented in [#9056](https://github.com/blockscout/blockscout/pull/9056).      | (empty)                                                    | v6.1.0+ | API         |

#### MUD framework

| Variable              | Required | Description                                                                                                                                                                                               | Default                   | Version | Application |
| --------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------- | ------- | ----------- |
| `MUD_INDEXER_ENABLED` |          | If `true`, integration with [MUD](https://mud.dev/services/indexer#schemaless-indexing-with-postgresql-via-docker) is enabled. Implemented in [#9869](https://github.com/blockscout/blockscout/pull/9869) | (empty)                   | v6.6.0+ | API         |
| `MUD_DATABASE_URL`    |          | MUD indexer DB connection URL.                                                                                                                                                                            | value from `DATABASE_URL` | v6.6.0+ | API         |
| `MUD_POOL_SIZE`       |          | MUD indexer DB `pool_size`                                                                                                                                                                                | 50                        | v6.6.0+ | API         |


# Frontend ENVs: Common
Source: https://docs.blockscout.com/setup/env-variables/frontend-common-envs



<Info>
  * [Full ENV List](/setup/env-variables/frontend-common-envs/envs) with example values and requirements
  * [**ENV File**](https://github.com/blockscout/frontend/blob/main/configs/envs/.env.eth) example
</Info>

Customize the UI of your running app instance (for example, homepage appearance, sidebar menu, and links in the footer) or enable certain features (like “My account’, “Marketplace”, “Blockchain interaction”, etc) by passing additional variables to your front-end container. These can be passed during runtime, added to the docker container in the `environment:` list, or changed within the `.env` file.


# Deprecated ENVs
Source: https://docs.blockscout.com/setup/env-variables/frontend-common-envs/deprecated-envs



<Note>
  Scroll Horizontally to view all information
</Note>

# Deprecated environment variables

| Variable                                         | Type            | Description                                                                                                                                              | Compulsoriness | Default value | Example value                             | Introduced in version | Deprecated in version | Comment                                                                      |
| ------------------------------------------------ | --------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ----------------------------------------- | --------------------- | --------------------- | ---------------------------------------------------------------------------- |
| NEXT\_PUBLIC\_FAVICON\_GENERATOR\_API\_KEY       | `string`        | RealFaviconGenerator [API key](https://realfavicongenerator.net/api/)                                                                                    | Required       | -             | `<your-secret>`                           | v1.11.0               | v1.16.0               | Replaced FAVICON\_GENERATOR\_API\_KEY                                        |
| FAVICON\_GENERATOR\_API\_KEY                     | `string`        | RealFaviconGenerator [API key](https://realfavicongenerator.net/api/)                                                                                    | Required       | -             | `<your-secret>`                           | v1.16.0+              | v1.37.0               | We don't use RealFaviconGenerator anymore                                    |
| NEXT\_PUBLIC\_IS\_OPTIMISTIC\_L2\_NETWORK        | `boolean`       | Set to true for optimistic L2 solutions                                                                                                                  | Required       | -             | `true`                                    | v1.17.0               | v1.24.0               | Replaced by NEXT\_PUBLIC\_ROLLUP\_TYPE                                       |
| NEXT\_PUBLIC\_IS\_ZKEVM\_L2\_NETWORK             | `boolean`       | Set to true for zkevm L2 solutions                                                                                                                       | Required       | -             | `true`                                    | v1.17.0               | v1.24.0               | Replaced by NEXT\_PUBLIC\_ROLLUP\_TYPE                                       |
| NEXT\_PUBLIC\_OPTIMISTIC\_L2\_WITHDRAWAL\_URL    | `string`        | URL for optimistic L2 -> L1 withdrawals                                                                                                                  | Required       | -             | `https://app.optimism.io/bridge/withdraw` | v1.17.0               | v1.24.0               | Renamed to NEXT\_PUBLIC\_ROLLUP\_L2\_WITHDRAWAL\_URL                         |
| NEXT\_PUBLIC\_L1\_BASE\_URL                      | `string`        | Blockscout base URL for L1 network                                                                                                                       | Required       | -             | `'http://eth-goerli.blockscout.com'`      | -                     | v1.24.0               | Renamed to NEXT\_PUBLIC\_ROLLUP\_L1\_BASE\_URL                               |
| NEXT\_PUBLIC\_HOMEPAGE\_SHOW\_GAS\_TRACKER       | `boolean`       | Set to false if network doesn't have gas tracker                                                                                                         | -              | `true`        | `false`                                   | -                     | v1.25.0               | Replaced by NEXT\_PUBLIC\_GAS\_TRACKER\_ENABLED                              |
| NEXT\_PUBLIC\_NETWORK\_GOVERNANCE\_TOKEN\_SYMBOL | `string`        | Network governance token symbol                                                                                                                          | -              | -             | `GNO`                                     | v1.12.0               | v1.29.0               | Replaced by NEXT\_PUBLIC\_NETWORK\_SECONDARY\_COIN\_SYMBOL                   |
| NEXT\_PUBLIC\_SWAP\_BUTTON\_URL                  | `string`        | Application ID in the marketplace or website URL                                                                                                         | -              | -             | `uniswap`                                 | v1.24.0               | v1.31.0               | Replaced by NEXT\_PUBLIC\_DEFI\_DROPDOWN\_ITEMS                              |
| NEXT\_PUBLIC\_HOMEPAGE\_SHOW\_AVG\_BLOCK\_TIME   | `boolean`       | Set to false if average block time is useless for the network                                                                                            | -              | `true`        | `false`                                   | v1.0.x+               | v1.35.0               | Replaced by NEXT\_PUBLIC\_HOMEPAGE\_STATS                                    |
| NEXT\_PUBLIC\_CELO\_L2\_UPGRADE\_BLOCK           | `number`        | Indicates the block number when the Celo-type chain transitioned to L2. This is used to display links to the Epoch block page from a regular block page. | -              | -             | `26369280`                                | v1.37.0+              | v2.2.0                | Removed; configuration done on the API side                                  |
| NEXT\_PUBLIC\_NAVIGATION\_HIDDEN\_LINKS          | `Array<LinkId>` | List of external links hidden in the navigation. Supported ids are `eth_rpc_api`, `rpc_api`                                                              | -              | -             | `['eth_rpc_api']`                         | v1.16.0+              | v2.3.0                | Use NEXT\_PUBLIC\_API\_DOCS\_TABS instead to hide tabs on the API docs page. |


# Frontend ENVs
Source: https://docs.blockscout.com/setup/env-variables/frontend-common-envs/envs



# ENVs

The app instance can be customized by passing variables to the Node.js environment at runtime.

* [Deprecated variables](/setup/env-variables/frontend-common-envs/deprecated-envs) are available here.
* ENV list is also available in the [frontend docs repo](https://github.com/blockscout/frontend/blob/main/docs/ENVS.md).

## Read before you run the app

### Variables compulsoriness

Please note that in the tables below, the "Compulsoriness" column indicates whether the variable is required for starting up the application, except for the "App Features" section. All features are optional by definition; therefore, the "Compulsoriness" column indicates whether a certain variable is required or optional only within the context of that feature, not for the entire application.

### Disclaimer about using variables

Please be aware that all environment variables prefixed with `NEXT_PUBLIC_` will be exposed to the browser. So any user can obtain its values. Make sure that for all 3rd-party services keys (e.g., Auth0, WalletConnect, etc.) in the services administration panel you have created a whitelist of allowed origins and have added your app domain into it. That will help you prevent using your key by unauthorized app, if someone gets its value.

### Note about escaping variables values

All json-like values should be single-quoted. If it contains a hash (`#`) or a dollar-sign (`$`) the whole value should be wrapped in single quotes as well (see `dotenv` [readme](https://github.com/bkeepers/dotenv#variable-substitution) for the reference)

<Note>
  Scroll horizontally to see all values in the variables tables.
</Note>

## Table of contents

* [App configuration](#app-configuration)
* [Blockchain parameters](#blockchain-parameters)
* [API configuration](#api-configuration)
* [UI configuration](#ui-configuration)
  * [Homepage](#homepage)
  * [Navigation](#navigation)
  * [Footer](#footer)
  * [Favicon](#favicon)
  * [Meta](#meta)
  * [Views](#views)
    * [Block](#block-views)
    * [Address](#address-views)
    * [Transaction](#transaction-views)
    * [NFT](#nft-views)
  * [Misc](#misc)
* [App features](#app-features)
  * [My account](#my-account)
  * [Gas tracker](#gas-tracker)
  * [Advanced filter](#advanced-filter)
  * [Address verification](#address-verification-in-my-account) in "My account"
  * [Blockchain interaction](#blockchain-interaction-writing-to-contract-etc) (writing to contract, etc.)
  * [Banner ads](#banner-ads)
  * [Text ads](#text-ads)
  * [Beacon chain](#beacon-chain)
  * [User operations](#user-operations-erc-4337)
  * [Rollup chain](#rollup-chain)
  * [Export data to CSV file](#export-data-to-csv-file)
  * [Google analytics](#google-analytics)
  * [Mixpanel analytics](#mixpanel-analytics)
  * [GrowthBook feature flagging and A/B testing](#growthbook-feature-flagging-and-ab-testing)
  * [GraphQL API documentation](#graphql-api-documentation)
  * [REST API documentation](#rest-api-documentation)
  * [Marketplace](#marketplace)
  * [Solidity to UML diagrams](#solidity-to-uml-diagrams)
  * [Blockchain statistics](#blockchain-statistics)
  * [Web3 wallet integration](#web3-wallet-integration-add-token-or-network-to-the-wallet) (add token or network to the wallet)
  * [Transaction interpretation](#transaction-interpretation)
  * [Verified tokens info](#verified-tokens-info)
  * [Name service integration](#name-service-integration)
  * [Metadata service integration](#metadata-service-integration)
  * [Public tag submission](#public-tag-submission)
  * [Data availability](#data-availability)
  * [Bridged tokens](#bridged-tokens)
  * [Safe address tags](#safecore-address-tags)
  * [Address profile API](#address-profile-api)
  * [Address XStar XHS score](#address-xstar-xhs-score)
  * [SUAVE chain](#suave-chain)
  * [Celo chain](#celo-chain)
  * [Ton Application Chain (TAC)](#ton-application-chain-tac)
  * [MetaSuites extension](#metasuites-extension)
  * [Validators list](#validators-list)
  * [Sentry error monitoring](#sentry-error-monitoring)
  * [Rollbar error monitoring](#rollbar-error-monitoring)
  * [OpenTelemetry](#opentelemetry)
  * [DeFi dropdown](#defi-dropdown)
  * [Multichain balance button](#multichain-balance-button)
  * [Get gas button](#get-gas-button)
  * [Save on gas with GasHawk](#save-on-gas-with-gashawk)
  * [Rewards service API](#rewards-service-api)
  * [DEX pools](#dex-pools)
* [3rd party services configuration](#external-services-configuration)

## App configuration

| Variable                           | Type            | Description                                                                                                                                                                                      | Compulsoriness | Default value | Example value      | Version |
| ---------------------------------- | --------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------- | ------------- | ------------------ | ------- |
| NEXT\_PUBLIC\_APP\_PROTOCOL        | `http \| https` | App url schema                                                                                                                                                                                   | -              | `https`       | `http`             | v1.0.x+ |
| NEXT\_PUBLIC\_APP\_HOST            | `string`        | App host                                                                                                                                                                                         | Required       | -             | `blockscout.com`   | v1.0.x+ |
| NEXT\_PUBLIC\_APP\_PORT            | `number`        | Port where app is running                                                                                                                                                                        | -              | `3000`        | `3001`             | v1.0.x+ |
| NEXT\_PUBLIC\_APP\_ENV             | `string`        | App env (e.g development, staging, production, etc.).                                                                                                                                            | -              | `production`  | `staging`          | v1.0.x+ |
| NEXT\_PUBLIC\_APP\_INSTANCE        | `string`        | Name of app instance. Used for app monitoring purposes. If not provided, it will be constructed from `NEXT_PUBLIC_APP_HOST`                                                                      | -              | -             | `wonderful_kepler` | v1.0.x+ |
| NEXT\_PUBLIC\_USE\_NEXT\_JS\_PROXY | `boolean`       | Tells the app to proxy all APIs request through the NextJS app. **We strongly advise not to use it in the production environment**, since it can lead to performance issues of the NodeJS server | -              | `false`       | `true`             | v1.8.0+ |

## Blockchain parameters

*Note!* The `NEXT_PUBLIC_NETWORK_CURRENCY` variables represent the blockchain's native token used for paying transaction fees. `NEXT_PUBLIC_NETWORK_SECONDARY_COIN` variables refer to tokens like protocol-specific tokens (e.g., OP token on Optimism chain) or governance tokens (e.g., GNO on Gnosis chain).

| Variable                                         | Type                      | Description                                                                                                                                                | Compulsoriness | Default value | Example value              | Version  |
| ------------------------------------------------ | ------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | -------------------------- | -------- |
| NEXT\_PUBLIC\_NETWORK\_NAME                      | `string`                  | Displayed name of the network                                                                                                                              | Required       | -             | `Gnosis Chain`             | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_SHORT\_NAME               | `string`                  | Used for SEO attributes (e.g, page description)                                                                                                            | -              | -             | `OoG`                      | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_ID                        | `number`                  | Chain id, see [https://chainlist.org](https://chainlist.org) for the reference                                                                             | Required       | -             | `99`                       | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_RPC\_URL                  | `string \| Array‹string›` | Chain public RPC server url, see [https://chainlist.org](https://chainlist.org) for the reference. Can contain a single string value, or an array of urls. | -              | -             | `https://core.poa.network` | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_NAME            | `string`                  | Network currency name                                                                                                                                      | -              | -             | `Ether`                    | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_WEI\_NAME       | `string`                  | Name of network currency subdenomination                                                                                                                   | -              | `wei`         | `duck`                     | v1.23.0+ |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_SYMBOL          | `string`                  | Network currency symbol                                                                                                                                    | -              | -             | `ETH`                      | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_DECIMALS        | `string`                  | Network currency decimals                                                                                                                                  | -              | `18`          | `6`                        | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_SECONDARY\_COIN\_SYMBOL   | `string`                  | Network secondary coin symbol.                                                                                                                             | -              | -             | `GNO`                      | v1.29.0+ |
| NEXT\_PUBLIC\_NETWORK\_MULTIPLE\_GAS\_CURRENCIES | `boolean`                 | Set to `true` for networks where users can pay transaction fees in either the native coin or ERC-20 tokens.                                                | -              | `false`       | `true`                     | v1.33.0+ |
| NEXT\_PUBLIC\_NETWORK\_VERIFICATION\_TYPE        | `validation \| mining`    | Verification type in the network. Irrelevant for Arbitrum (verification type is always `posting`) and ZkEvm (verification type is always `sequencing`) L2s | -              | `mining`      | `validation`               | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_TOKEN\_STANDARD\_NAME     | `string`                  | Name of the standard for creating tokens                                                                                                                   | -              | `ERC`         | `BEP`                      | v1.31.0+ |
| NEXT\_PUBLIC\_IS\_TESTNET                        | `boolean`                 | Set to true if network is testnet                                                                                                                          | -              | `false`       | `true`                     | v1.0.x+  |

## API configuration

| Variable                               | Type            | Description                           | Compulsoriness | Default value | Example value    | Version |
| -------------------------------------- | --------------- | ------------------------------------- | -------------- | ------------- | ---------------- | ------- |
| NEXT\_PUBLIC\_API\_PROTOCOL            | `http \| https` | Main API protocol                     | -              | `https`       | `http`           | v1.0.x+ |
| NEXT\_PUBLIC\_API\_HOST                | `string`        | Main API host                         | Required       | -             | `blockscout.com` | v1.0.x+ |
| NEXT\_PUBLIC\_API\_PORT                | `number`        | Port where API is running on the host | -              | -             | `3001`           | v1.0.x+ |
| NEXT\_PUBLIC\_API\_BASE\_PATH          | `string`        | Base path for Main API endpoint url   | -              | -             | `/poa/core`      | v1.0.x+ |
| NEXT\_PUBLIC\_API\_WEBSOCKET\_PROTOCOL | `ws \| wss`     | Main API websocket protocol           | -              | `wss`         | `ws`             | v1.0.x+ |

## UI configuration

### Homepage

| Variable                                     | Type                                                                                                                                                                                         | Description                                                                                                                                                                                            | Compulsoriness | Default value                                                                                                                                                                                                                       | Example value                                                                                                                                      | Version  |
| -------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_HOMEPAGE\_CHARTS               | `Array‹daily_txs \| daily_operational_txs \| coin_price \| secondary_coin_price \| market_cap \| tvl›`                                                                                       | List of charts displayed on the home page                                                                                                                                                              | -              | -                                                                                                                                                                                                                                   | `["daily_txs","coin_price","market_cap"]`                                                                                                          | v1.0.x+  |
| NEXT\_PUBLIC\_HOMEPAGE\_STATS                | `Array‹latest_batch \| total_blocks \| average_block_time \| total_txs \| total_operational_txs \| latest_l1_state_batch \| wallet_addresses \| gas_tracker \| btc_locked \| current_epoch›` | List of stats widgets displayed on the home page                                                                                                                                                       | -              | For zkSync, zkEvm and Arbitrum rollups: `["latest_batch","average_block_time","total_txs","wallet_addresses","gas_tracker"]`, for other cases: `["total_blocks","average_block_time","total_txs","wallet_addresses","gas_tracker"]` | `["total_blocks","total_txs","wallet_addresses"]`                                                                                                  | v1.35.x+ |
| NEXT\_PUBLIC\_HOMEPAGE\_PLATE\_TEXT\_COLOR   | `string`                                                                                                                                                                                     | Text color of the hero plate on the homepage (escape "#" symbol if you use HEX color codes or use rgba-value instead). **DEPRECATED** **`Use NEXT_PUBLIC_HOMEPAGE_HERO_BANNER_CONFIG instead`**        | -              | `white`                                                                                                                                                                                                                             | `\\#DCFE76`                                                                                                                                        | v1.0.x+  |
| NEXT\_PUBLIC\_HOMEPAGE\_PLATE\_BACKGROUND    | `string`                                                                                                                                                                                     | Background css value for hero plate on the homepage (escape "#" symbol if you use HEX color codes or use rgba-value instead). **DEPRECATED** **`Use NEXT_PUBLIC_HOMEPAGE_HERO_BANNER_CONFIG instead`** | -              | `radial-gradient(103.03% 103.03% at 0% 0%, rgba(183, 148, 244, 0.8) 0%, rgba(0, 163, 196, 0.8) 100%), var(--chakra-colors-blue-400)`                                                                                                | `radial-gradient(at 15% 86%, hsla(350,65%,70%,1) 0px, transparent 50%)` \| `no-repeat bottom 20% right 0px/100% url(https://placekitten/1400/200)` | v1.1.0+  |
| NEXT\_PUBLIC\_HOMEPAGE\_HERO\_BANNER\_CONFIG | `HeroBannerConfig`, see details [below](/setup/env-variables/frontend-common-envs/envs#hero-banner-configuration-properties)                                                                 | Configuration of hero banner appearance.                                                                                                                                                               | -              | -                                                                                                                                                                                                                                   | See [below](/setup/env-variables/frontend-common-envs/envs#hero-banner-configuration-properties)                                                   | v1.35.0+ |

#### Hero banner configuration properties

*Note* Here, all values are arrays of up to two strings. The first string represents the value for the light color mode, and the second string represents the value for the dark color mode. If the array contains only one string, it will be used for both color modes.

| Variable    | Type                                                                                                             | Description                                                                                                                                                                                       | Compulsoriness | Default value                                                                                                                          | Example value                                                                       |
| ----------- | ---------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | -------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| background  | `[string, string]`                                                                                               | Banner background (could be a solid color, gradient or picture). The string should be a valid `background` CSS property value.                                                                    | -              | `[radial-gradient(103.03% 103.03% at 0% 0%, rgba(183, 148, 244, 0.8) 0%, rgba(0, 163, 196, 0.8) 100%), var(--chakra-colors-blue-400)]` | `[lightpink,no-repeat bottom 20% right 0px/100% url(https://placekitten/1400/200)]` |
| text\_color | `[string, string]`                                                                                               | Banner text background. The string should be a valid `color` CSS property value.                                                                                                                  | -              | `[white]`                                                                                                                              | `[lightpink,\\#DCFE76]`                                                             |
| border      | `[string, string]`                                                                                               | Banner border. The string should be a valid `border` CSS property value.                                                                                                                          | -              | -                                                                                                                                      | `[1px solid yellow,4px dashed \\#DCFE76]`                                           |
| button      | `Partial‹Record‹_default \| hover \| selected, {background?: [string, string]; text_color?: [string, string]}››` | The button on the banner. It has three possible states: `_default`, `_hover`, and `_selected`. The `_selected` state reflects when the user is logged in or their wallet is connected to the app. | -              | -                                                                                                                                      | `{_default: {background: [deeppink], text_color: [white]}}`                         |

### Navigation

| Variable                                      | Type                                 | Description                                                                                                                                                                                                                                                                                                                    | Compulsoriness | Default value | Example value                                                                                                                                                                     | Version  |
| --------------------------------------------- | ------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------- | ------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_NETWORK\_LOGO                   | `string`                             | Network logo; if not provided, placeholder will be shown; *Note* the logo height should be 24px and width less than 120px                                                                                                                                                                                                      | -              | -             | `https://placekitten.com/240/40`                                                                                                                                                  | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_LOGO\_DARK             | `string`                             | Network logo for dark color mode; if not provided, **inverted** regular logo will be used instead                                                                                                                                                                                                                              | -              | -             | `https://placekitten.com/240/40`                                                                                                                                                  | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_ICON                   | `string`                             | Network icon; used as a replacement for regular network logo when nav bar is collapsed; if not provided, placeholder will be shown; *Note* the icon size should be at least 60px by 60px                                                                                                                                       | -              | -             | `https://placekitten.com/60/60`                                                                                                                                                   | v1.0.x+  |
| NEXT\_PUBLIC\_NETWORK\_ICON\_DARK             | `string`                             | Network icon for dark color mode; if not provided, **inverted** regular icon will be used instead                                                                                                                                                                                                                              | -              | -             | `https://placekitten.com/60/60`                                                                                                                                                   | v1.0.x+  |
| NEXT\_PUBLIC\_FEATURED\_NETWORKS              | `string`                             | URL of configuration file (`.json` format only) or file content string representation. It contains list of featured networks that will be shown in the network menu. See [below](/setup/env-variables/frontend-common-envs/envs#featured-network-configuration-properties) list of available properties for particular network | -              | -             | `https://example.com/featured_networks_config.json` \| `[{"title":"Astar(EVM)","url":"https://astar.blockscout.com/","group":"Mainnets","icon":"https://example.com/astar.svg"}]` | v1.0.x+  |
| NEXT\_PUBLIC\_OTHER\_LINKS                    | `Array‹{url: string; text: string}›` | List of links for the "Other" navigation menu                                                                                                                                                                                                                                                                                  | -              | -             | `[{"url":"https://blockscout.com","text":"Blockscout"}]`                                                                                                                          | v1.0.x+  |
| NEXT\_PUBLIC\_NAVIGATION\_HIDDEN\_LINKS       | `Array‹LinkId›`                      | List of external links hidden in the navigation. Supported ids are `eth_rpc_api`, `rpc_api`                                                                                                                                                                                                                                    | -              | -             | `["eth_rpc_api"]`                                                                                                                                                                 | v1.16.0+ |
| NEXT\_PUBLIC\_NAVIGATION\_HIGHLIGHTED\_ROUTES | `Array‹string›`                      | List of menu item routes that should have a lightning label                                                                                                                                                                                                                                                                    | -              | -             | `["/accounts"]`                                                                                                                                                                   | v1.31.0+ |
| NEXT\_PUBLIC\_NAVIGATION\_LAYOUT              | `vertical \| horizontal`             | Navigation menu layout type                                                                                                                                                                                                                                                                                                    | -              | `vertical`    | `horizontal`                                                                                                                                                                      | v1.32.0+ |

#### Featured network configuration properties

| Variable             | Type                            | Description                                                                                                                | Compulsoriness | Default value | Example value                         |
| -------------------- | ------------------------------- | -------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------- |
| title                | `string`                        | Displayed name of the network                                                                                              | Required       | -             | `Gnosis Chain`                        |
| url                  | `string`                        | Network explorer main page url                                                                                             | Required       | -             | `https://blockscout.com/xdai/mainnet` |
| group                | `Mainnets \| Testnets \| Other` | Indicates in which tab network appears in the menu                                                                         | Required       | -             | `Mainnets`                            |
| icon                 | `string`                        | Network icon; if not provided, the common placeholder will be shown; *Note* that icon size should be at least 60px by 60px | -              | -             | `https://placekitten.com/60/60`       |
| isActive             | `boolean`                       | Pass `true` if item should be shown as active in the menu                                                                  | -              | -             | `true`                                |
| invertIconInDarkMode | `boolean`                       | Pass `true` if icon colors should be inverted in dark mode                                                                 | -              | -             | `true`                                |

### Footer

| Variable                    | Type     | Description                                                                                                                                                                                                                                                                                               | Compulsoriness | Default value | Example value                                                                                                                                                                                    | Version |
| --------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------- |
| NEXT\_PUBLIC\_FOOTER\_LINKS | `string` | URL of configuration file (`.json` format only) or file content string representation. It contains list of link groups to be displayed in the footer. See [below](/setup/env-variables/frontend-common-envs/envs#footer-links-configuration-properties) list of available properties for particular group | -              | -             | `https://example.com/footer_links_config.json` \| `[{"title":"My chain","links":[{"text":"About","url":"https://example.com/about"},{"text":"Contacts","url":"https://example.com/contacts"}]}]` | v1.1.1+ |

The app version shown in the footer is derived from build-time ENV variables `NEXT_PUBLIC_GIT_TAG` and `NEXT_PUBLIC_GIT_COMMIT_SHA` and cannot be overwritten at run-time.

#### Footer links configuration properties

| Variable | Type                                   | Description         | Compulsoriness | Default value | Example value                                              |
| -------- | -------------------------------------- | ------------------- | -------------- | ------------- | ---------------------------------------------------------- |
| title    | `string`                               | Title of link group | Required       | -             | `Company`                                                  |
| links    | `Array‹{"text":string;"url":string;}›` | list of links       | Required       | -             | `[{"text":"Homepage","url":"https://www.blockscout.com"}]` |

### Favicon

By default, the app has generic favicon. You can override this behavior by providing the following variable. Hence, the favicon assets bundle will be generated at the container start time and will be used instead of default one.

| Variable             | Type     | Description | Compulsoriness | Default value              | Example value                     | Version  |
| -------------------- | -------- | ----------- | -------------- | -------------------------- | --------------------------------- | -------- |
| FAVICON\_MASTER\_URL | `string` | -           | -              | `NEXT_PUBLIC_NETWORK_ICON` | `https://placekitten.com/180/180` | v1.11.0+ |

### Meta

Settings for meta tags, OG tags and SEO

| Variable                                     | Type      | Description                                                                                                                                                                               | Compulsoriness | Default value               | Example value                                                                                                                                                                                              | Version  |
| -------------------------------------------- | --------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | --------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_PROMOTE\_BLOCKSCOUT\_IN\_TITLE | `boolean` | Set to `true` to promote Blockscout in meta and OG titles                                                                                                                                 | -              | `true`                      | `true`                                                                                                                                                                                                     | v1.12.0+ |
| NEXT\_PUBLIC\_OG\_DESCRIPTION                | `string`  | Custom OG description                                                                                                                                                                     | -              | -                           | `Open-source block explorer by Blockscout. Search transactions, verify smart contracts, analyze addresses, and track network activity. Complete blockchain data and APIs for the %network_title% network.` | v1.12.0+ |
| NEXT\_PUBLIC\_OG\_IMAGE\_URL                 | `string`  | OG image url. Minimum image size is 200 x 20 pixels (recommended: 1200 x 600); maximum supported file size is 8 MB; 2:1 aspect ratio; supported formats: image/jpeg, image/gif, image/png | -              | `static/og_placeholder.png` | `https://placekitten.com/1200/600`                                                                                                                                                                         | v1.12.0+ |
| NEXT\_PUBLIC\_OG\_ENHANCED\_DATA\_ENABLED    | `boolean` | Set to `true` to populate OG tags (title, description) with API data for social preview robot requests                                                                                    | -              | `false`                     | `true`                                                                                                                                                                                                     | v1.29.0+ |
| NEXT\_PUBLIC\_SEO\_ENHANCED\_DATA\_ENABLED   | `boolean` | Set to `true` to pre-render page titles (e.g Token page) on the server side and inject page h1-tag to the markup before it is sent to the browser.                                        | -              | `false`                     | `true`                                                                                                                                                                                                     | v1.30.0+ |

### Views

#### Block views

| Variable                                   | Type                  | Description                                                                                        | Compulsoriness | Default value | Example value                   | Version  |
| ------------------------------------------ | --------------------- | -------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------- | -------- |
| NEXT\_PUBLIC\_VIEWS\_BLOCK\_HIDDEN\_FIELDS | `Array‹BlockFieldId›` | Array of the block fields ids that should be hidden. See below the list of the possible id values. | -              | -             | `["burnt_fees","total_reward"]` | v1.10.0+ |

**Block fields list**

| Id             | Description                                                                |
| -------------- | -------------------------------------------------------------------------- |
| `base_fee`     | Base fee                                                                   |
| `burnt_fees`   | Burnt fees                                                                 |
| `total_reward` | Total block reward                                                         |
| `nonce`        | Block nonce                                                                |
| `miner`        | Address of block's miner or validator                                      |
| `L1_status`    | Short interpretation of the batch lifecycle (applicable for Rollup chains) |
| `batch`        | Batch index (applicable for Rollup chains)                                 |

#### Address views

| Variable                                                    | Type                                                        | Description                                                                                                                                                                                                                                                                                                                                             | Compulsoriness                                                          | Default value                | Example value                         | Version  |
| ----------------------------------------------------------- | ----------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------- | ---------------------------- | ------------------------------------- | -------- |
| NEXT\_PUBLIC\_VIEWS\_ADDRESS\_IDENTICON\_TYPE               | `github \| jazzicon \| gradient_avatar \| blockie \| nouns` | Default style of address identicon appearance. Choose between [GitHub](https://github.blog/2013-08-14-identicons/), [Metamask Jazzicon](https://metamask.github.io/jazzicon/), [Gradient Avatar](https://github.com/varld/gradient-avatar), [Ethereum Blocky](https://mycryptohq.github.io/ethereum-blockies-base64/) and [Nouns](https://nouns.wtf)    | -                                                                       | `jazzicon`                   | `gradient_avatar`                     | v1.12.0+ |
| NEXT\_PUBLIC\_VIEWS\_ADDRESS\_FORMAT                        | `Array‹"base16" \| "bech32"›`                               | Displayed address format, could be either `base16` standard or [`bech32`](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki#bech32) standard. If the array contains multiple values, the address format toggle will appear in the UI, allowing the user to switch between formats. The first item in the array will be the default format. | -                                                                       | `["base16"]`                 | `["bech32", "base16"]`                | v1.36.0+ |
| NEXT\_PUBLIC\_VIEWS\_ADDRESS\_BECH\_32\_PREFIX              | `string`                                                    | Human-readable prefix of `bech32` address format.                                                                                                                                                                                                                                                                                                       | Required, if `NEXT_PUBLIC_VIEWS_ADDRESS_FORMAT` contains "bech32" value | -                            | `duck`                                | v1.36.0+ |
| NEXT\_PUBLIC\_VIEWS\_ADDRESS\_HIDDEN\_VIEWS                 | `Array‹AddressViewId›`                                      | Address views that should not be displayed. See below the list of the possible id values.                                                                                                                                                                                                                                                               | -                                                                       | -                            | `["top_accounts"]`                    | v1.15.0+ |
| NEXT\_PUBLIC\_VIEWS\_CONTRACT\_SOLIDITYSCAN\_ENABLED        | `boolean`                                                   | Set to `true` if SolidityScan reports are supported                                                                                                                                                                                                                                                                                                     | -                                                                       | -                            | `true`                                | v1.19.0+ |
| NEXT\_PUBLIC\_VIEWS\_CONTRACT\_EXTRA\_VERIFICATION\_METHODS | `Array‹"solidity-hardhat" \| "solidity-foundry"›`           | Pass an array of additional methods from which users can choose while verifying a smart contract. Both methods are available by default, pass `none` string to disable them all.                                                                                                                                                                        | -                                                                       | -                            | `["solidity-hardhat"]`                | v1.33.0+ |
| NEXT\_PUBLIC\_VIEWS\_CONTRACT\_LANGUAGE\_FILTERS            | `Array‹"solidity" \| "vyper" \| "yul" \| "scilla"›`         | Pass an array of contract languages that will be displayed as options in the filter on the verified contract page.                                                                                                                                                                                                                                      | -                                                                       | `["solidity","vyper","yul"]` | `["solidity","vyper","yul","scilla"]` | v1.37.0+ |

**Address views list**

| Id             | Description  |
| -------------- | ------------ |
| `top_accounts` | Top accounts |

#### Transaction views

| Variable                                    | Type                          | Description                                                                                                                       | Compulsoriness | Default value | Example value        | Version  |
| ------------------------------------------- | ----------------------------- | --------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | -------------------- | -------- |
| NEXT\_PUBLIC\_VIEWS\_TX\_HIDDEN\_FIELDS     | `Array‹TxFieldsId›`           | Array of the transaction fields ids that should be hidden. See below the list of the possible id values.                          | -              | -             | `["value","tx_fee"]` | v1.15.0+ |
| NEXT\_PUBLIC\_VIEWS\_TX\_ADDITIONAL\_FIELDS | `Array‹TxAdditionalFieldsId›` | Array of the additional fields ids that should be added to the transaction details. See below the list of the possible id values. | -              | -             | `["fee_per_gas"]`    | v1.15.0+ |

**Transaction fields list**

| Id             | Description                                                                |
| -------------- | -------------------------------------------------------------------------- |
| `value`        | Sent value                                                                 |
| `fee_currency` | Fee currency                                                               |
| `gas_price`    | Price per unit of gas                                                      |
| `tx_fee`       | Total transaction fee                                                      |
| `gas_fees`     | Gas fees breakdown                                                         |
| `burnt_fees`   | Amount of native coin burnt for transaction                                |
| `L1_status`    | Short interpretation of the batch lifecycle (applicable for Rollup chains) |
| `batch`        | Batch index (applicable for Rollup chains)                                 |

**Transaction additional fields list**

| Id            | Description                                                            |
| ------------- | ---------------------------------------------------------------------- |
| `fee_per_gas` | Amount of total fee divided by total amount of gas used by transaction |

#### Token views

| Variable                                          | Type      | Description                                                                                                                                                   | Compulsoriness | Default value | Example value | Version  |
| ------------------------------------------------- | --------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_VIEWS\_TOKEN\_SCAM\_TOGGLE\_ENABLED | `boolean` | Show the "Hide scam tokens" toggle in the site settings dropdown. This option controls the visibility of tokens with a poor reputation in the search results. | -              | `false`       | `true`        | v1.38.0+ |

#### NFT views

| Variable                                      | Type                                                                                                                                                      | Description                                                                                                                                                                                                                                                      | Compulsoriness | Default value | Example value                                                                                                                                                                                                            | Version  |
| --------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------- |
| NEXT\_PUBLIC\_VIEWS\_NFT\_MARKETPLACES        | `Array‹NftMarketplace›` where `NftMarketplace` can have following [properties](/setup/env-variables/frontend-common-envs/envs#nft-marketplace-properties) | Used to build up links to NFT collections and NFT instances in external marketplaces.                                                                                                                                                                            | -              | -             | `[{"name":"OpenSea","collection_url":"https://opensea.io/assets/ethereum/{hash}","instance_url":"https://opensea.io/assets/ethereum/{hash}/{id}","logo_url":"https://opensea.io/static/images/logos/opensea-logo.svg"}]` | v1.15.0+ |
| NEXT\_PUBLIC\_HELIA\_VERIFIED\_FETCH\_ENABLED | `boolean`                                                                                                                                                 | Indicates that the [Helia verified fetch](https://github.com/ipfs/helia-verified-fetch/tree/main/packages/verified-fetch) should be used for retrieving content of NFT assets (currently limited to images) directly from IPFS network using trustless gateways. | -              | `true`        | `false`                                                                                                                                                                                                                  | v1.37.0+ |

**NFT marketplace properties**

| Variable        | Type     | Description                       | Compulsoriness | Default value | Example value                                             |
| --------------- | -------- | --------------------------------- | -------------- | ------------- | --------------------------------------------------------- |
| name            | `string` | Displayed name of the marketplace | Required       | -             | `OpenSea`                                                 |
| collection\_url | `string` | URL template for NFT collection   | Required       | -             | `https://opensea.io/assets/ethereum/{hash}`               |
| instance\_url   | `string` | URL template for NFT instance     | Required       | -             | `https://opensea.io/assets/ethereum/{hash}/{id}`          |
| logo\_url       | `string` | URL of marketplace logo           | Required       | -             | `https://opensea.io/static/images/logos/opensea-logo.svg` |

*Note* URL templates should contain placeholders of NFT hash (`{hash}`) and NFT id (`{id}`). This placeholders will be substituted with particular values for every collection or instance.

### Misc

| Variable                                      | Type                                                                                                                                                                        | Description                                                                                                             | Compulsoriness | Default value | Example value                                                                                                                                | Version  |
| --------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | -------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_NETWORK\_EXPLORERS              | `Array‹NetworkExplorer›` where `NetworkExplorer` can have following [properties](/setup/env-variables/frontend-common-envs/envs#network-explorer-configuration-properties)  | Used to build up links to transactions, blocks, addresses in other chain explorers.                                     | -              | -             | `[{"title":"Anyblock","baseUrl":"https://explorer.anyblock.tools","paths":{"tx":"/ethereum/poa/core/tx"}}]`                                  | v1.0.x+  |
| NEXT\_PUBLIC\_CONTRACT\_CODE\_IDES            | `Array‹ContractCodeIde›` where `ContractCodeIde` can have following [properties](/setup/env-variables/frontend-common-envs/envs#contract-code-ide-configuration-properties) | Used to build up links to IDEs with contract source code.                                                               | -              | -             | `[{"title":"Remix IDE","url":"https://remix.blockscout.com/?address={hash}&blockscout={domain}","icon_url":"https://example.com/icon.svg"}]` | v1.23.0+ |
| NEXT\_PUBLIC\_HAS\_CONTRACT\_AUDIT\_REPORTS   | `boolean`                                                                                                                                                                   | Set to `true` to enable Submit Audit form on the contract page                                                          | -              | `false`       | `true`                                                                                                                                       | v1.25.0+ |
| NEXT\_PUBLIC\_HIDE\_INDEXING\_ALERT\_BLOCKS   | `boolean`                                                                                                                                                                   | Set to `true` to hide indexing alert in the page header about indexing chain's blocks                                   | -              | `false`       | `true`                                                                                                                                       | v1.17.0+ |
| NEXT\_PUBLIC\_HIDE\_INDEXING\_ALERT\_INT\_TXS | `boolean`                                                                                                                                                                   | Set to `true` to hide indexing alert in the page footer about indexing block's internal transactions                    | -              | `false`       | `true`                                                                                                                                       | v1.17.0+ |
| NEXT\_PUBLIC\_MAINTENANCE\_ALERT\_MESSAGE     | `string`                                                                                                                                                                    | Used for displaying custom announcements or alerts in the header of the site. Could be a regular string or a HTML code. | -              | -             | `Hello world! 🤪`                                                                                                                            | v1.13.0+ |
| NEXT\_PUBLIC\_COLOR\_THEME\_DEFAULT           | `light \| dim \| midnight \| dark`                                                                                                                                          | Preferred color theme of the app                                                                                        | -              | -             | `midnight`                                                                                                                                   | v1.30.0+ |
| NEXT\_PUBLIC\_FONT\_FAMILY\_HEADING           | `FontFamily`, see full description [below](/setup/env-variables/frontend-common-envs/envs#font-family-configuration-properties)                                             | Special typeface to use in page headings (`<h1>`, `<h2>`, etc.)                                                         | -              | -             | `{"name":"Montserrat","url":"https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700&display=swap"}`                        | v1.35.0+ |
| NEXT\_PUBLIC\_FONT\_FAMILY\_BODY              | `FontFamily`, see full description [below](/setup/env-variables/frontend-common-envs/envs#font-family-configuration-properties)                                             | Main typeface to use in page content elements.                                                                          | -              | -             | `{"name":"Raleway","url":"https://fonts.googleapis.com/css2?family=Raleway:wght@400;500;600;700&display=swap"}`                              | v1.35.0+ |
| NEXT\_PUBLIC\_MAX\_CONTENT\_WIDTH\_ENABLED    | `boolean`                                                                                                                                                                   | Set to `true` to restrict the page content width on extra-large screens.                                                | -              | `true`        | `false`                                                                                                                                      | v1.34.1+ |

#### Network explorer configuration properties

| Variable | Type                                                      | Description                                                                                                                        | Compulsoriness | Default value | Example value                     |
| -------- | --------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------------------------- |
| logo     | `string`                                                  | URL to explorer logo file. Should be at least 40x40.                                                                               | -              | -             | `https://foo.app/icon.png`        |
| title    | `string`                                                  | Displayed name of the explorer                                                                                                     | Required       | -             | `Anyblock`                        |
| baseUrl  | `string`                                                  | Base url of the explorer                                                                                                           | Required       | -             | `https://explorer.anyblock.tools` |
| paths    | `Record‹"tx" \| "block" \| "address" \| "token", string›` | Map of explorer entities and their paths. Path can be a template with `:id` or `:id_lowercase` param, or a string (see note below) | Required       | -             | `{"tx":"/ethereum/poa/core/tx"}`  |

*Note* If a path template contains `:id` or `:id_lowercase`, it will be replaced with the entity-id in its original case or lowercased respectively. If neither parameter is present, the entity-id will be appended to the end of the path in lowercase. For example, with baseUrl `https://explorer.anyblock.tools`:

* Path `{"tx":"/ethereum/poa/core/tx/:id/details"}` and entity-id `0x123...AbC` results in `https://explorer.anyblock.tools/ethereum/poa/core/tx/0x123...AbC/details`
* Path `{"tx":"/ethereum/poa/core/tx/:id_lowercase/details"}` and entity-id `0x123...AbC` results in `https://explorer.anyblock.tools/ethereum/poa/core/tx/0x123...abc/details`
* Path `{"tx":"/ethereum/poa/core/tx"}` and entity-id `0x123...AbC` results in `https://explorer.anyblock.tools/ethereum/poa/core/tx/0x123...abc`

#### Contract code IDE configuration properties

| Variable  | Type     | Description                                                                                   | Compulsoriness | Default value | Example value                                                      |
| --------- | -------- | --------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------------------------------ |
| title     | `string` | Displayed name of the IDE                                                                     | Required       | -             | `Remix IDE`                                                        |
| url       | `string` | URL of the IDE with placeholders for contract hash (`{hash}`) and current domain (`{domain}`) | Required       | -             | `https://remix.blockscout.com/?address={hash}&blockscout={domain}` |
| icon\_url | `string` | URL of the IDE icon                                                                           | Required       | -             | `https://example.com/icon.svg`                                     |

#### Font family configuration properties

| Variable | Type     | Description                                                                                    | Compulsoriness | Default value | Example value                                                                           |
| -------- | -------- | ---------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------------------------------------------------------------------------------- |
| name     | `string` | Font family name; used to define the `font-family` CSS property.                               | Required       | -             | `Montserrat`                                                                            |
| url      | `string` | URL for external font. Ensure the font supports the following weights: 400, 500, 600, and 700. | Required       | -             | `https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700&display=swap` |

## App features

*Note* The variables which are marked as required should be passed as described in order to enable the particular feature, but they are not required in the entire app context.

### My account

| Variable                                  | Type      | Description                                                                                                                                                                                                                             | Compulsoriness | Default value | Example value                                  | Version |
| ----------------------------------------- | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ---------------------------------------------- | ------- |
| NEXT\_PUBLIC\_IS\_ACCOUNT\_SUPPORTED      | `boolean` | Set to true if network has account feature                                                                                                                                                                                              | Required       | -             | `true`                                         | v1.0.x+ |
| NEXT\_PUBLIC\_RE\_CAPTCHA\_APP\_SITE\_KEY | `boolean` | See [below](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#google-recaptcha)                                                                                                           | Required       | -             | `<your-secret>`                                | v1.0.x+ |
| NEXT\_PUBLIC\_AUTH0\_CLIENT\_ID           | `string`  | **DEPRECATED** Client id for [Auth0](https://auth0.com/) provider                                                                                                                                                                       | -              | -             | `<your-secret>`                                | v1.0.x+ |
| NEXT\_PUBLIC\_AUTH\_URL                   | `string`  | **DEPRECATED** Account auth base url; it is used for building login URL (`${ NEXT_PUBLIC_AUTH_URL }/auth/auth0`) and logout return URL (`${ NEXT_PUBLIC_AUTH_URL }/auth/logout`); if not provided the base app URL will be used instead | -              | -             | `https://blockscout.com`                       | v1.0.x+ |
| NEXT\_PUBLIC\_LOGOUT\_URL                 | `string`  | **DEPRECATED** Account logout url. Required if account is supported for the app instance.                                                                                                                                               | -              | -             | `https://blockscoutcom.us.auth0.com/v2/logout` | v1.0.x+ |

### Gas tracker

This feature is **enabled by default**. To switch it off pass `NEXT_PUBLIC_GAS_TRACKER_ENABLED=false`.

| Variable                            | Type                     | Description                                                                                                                                                                                                                                                                                             | Compulsoriness | Default value       | Example value | Version  |
| ----------------------------------- | ------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------------- | ------------- | -------- |
| NEXT\_PUBLIC\_GAS\_TRACKER\_ENABLED | `boolean`                | Set to true to enable "Gas tracker" in the app                                                                                                                                                                                                                                                          | Required       | `true`              | `false`       | v1.25.0+ |
| NEXT\_PUBLIC\_GAS\_TRACKER\_UNITS   | `Array‹"usd" \| "gwei"›` | Array of units for displaying gas prices on the Gas Tracker page, in the stats snippet on the Home page, and in the top bar. The first value in the array will take priority over the second one in all mentioned views. If only one value is provided, gas prices will be displayed only in that unit. | -              | `[ "usd", "gwei" ]` | `[ "gwei" ]`  | v1.25.0+ |

### Advanced filter

This feature is **enabled by default**. To switch it off pass `NEXT_PUBLIC_ADVANCED_FILTER_ENABLED=false`.

| Variable                                | Type      | Description                                             | Compulsoriness | Default value | Example value | Version  |
| --------------------------------------- | --------- | ------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_ADVANCED\_FILTER\_ENABLED | `boolean` | Set to true to enable "Advanced filter" page in the app | Required       | `true`        | `false`       | v1.37.0+ |

### Address verification in "My account"

*Note* all ENV variables required for [My account](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#my-account) feature should be passed alongside the following ones:

| Variable                                | Type     | Description                    | Compulsoriness | Default value | Example value                                    | Version |
| --------------------------------------- | -------- | ------------------------------ | -------------- | ------------- | ------------------------------------------------ | ------- |
| NEXT\_PUBLIC\_CONTRACT\_INFO\_API\_HOST | `string` | Contract Info API endpoint url | Required       | -             | `https://contracts-info.services.blockscout.com` | v1.1.0+ |
| NEXT\_PUBLIC\_ADMIN\_SERVICE\_API\_HOST | `string` | Admin Service API endpoint url | Required       | -             | `https://admin-rs.services.blockscout.com`       | v1.1.0+ |

### Blockchain interaction (writing to contract, etc.)

| Variable                                   | Type     | Description                                                                                                                                                   | Compulsoriness | Default value | Example value              | Version |
| ------------------------------------------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | -------------------------- | ------- |
| NEXT\_PUBLIC\_WALLET\_CONNECT\_PROJECT\_ID | `string` | Project id for [WalletConnect](https://cloud.walletconnect.com/) integration                                                                                  | Required       | -             | `<your-secret>`            | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_RPC\_URL            | `string` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | Required       | -             | `https://core.poa.network` | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_NAME                | `string` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | Required       | -             | `Gnosis Chain`             | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_ID                  | `number` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | Required       | -             | `99`                       | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_NAME      | `string` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | Required       | -             | `Ether`                    | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_SYMBOL    | `string` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | Required       | -             | `ETH`                      | v1.0.x+ |
| NEXT\_PUBLIC\_NETWORK\_CURRENCY\_DECIMALS  | `string` | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section | -              | `18`          | `6`                        | v1.0.x+ |

### Banner ads

<Note>
  Ads are enabled by default on all self-hosted instances. If you would like to disable ads, you can disable using the [Autoscout hosted service](/using-blockscout/autoscout).
</Note>

### Text ads

<Note>
  Ads are enabled by default on all self-hosted instances. If you would like to disable ads, you can disable using the [Autoscout hosted service](/using-blockscout/autoscout).
</Note>

### Beacon chain

| Variable                                      | Type      | Description                                    | Compulsoriness | Default value                         | Example value | Version |
| --------------------------------------------- | --------- | ---------------------------------------------- | -------------- | ------------------------------------- | ------------- | ------- |
| NEXT\_PUBLIC\_HAS\_BEACON\_CHAIN              | `boolean` | Set to true for networks with the beacon chain | Required       | -                                     | `true`        | v1.0.x+ |
| NEXT\_PUBLIC\_BEACON\_CHAIN\_CURRENCY\_SYMBOL | `string`  | Beacon network currency symbol                 | -              | `NEXT_PUBLIC_NETWORK_CURRENCY_SYMBOL` | `ETH`         | v1.0.x+ |

### User operations (ERC-4337)

| Variable                     | Type      | Description                                                | Compulsoriness | Default value | Example value | Version  |
| ---------------------------- | --------- | ---------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_HAS\_USER\_OPS | `boolean` | Set to true to show user operations related data and pages | -              | -             | `true`        | v1.23.0+ |

### Rollup chain

| Variable                                             | Type                                                                                                                     | Description                                                                                                                                                                                                                                                                                                  | Compulsoriness                    | Default value | Example value                                                  | Version  |
| ---------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------------------- | ------------- | -------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_ROLLUP\_TYPE                           | `"optimistic" \| "arbitrum" \| "shibarium" \| "zkEvm" \| "zkSync" \| "scroll"`                                           | Rollup chain type                                                                                                                                                                                                                                                                                            | Required                          | -             | `"optimistic"`                                                 | v1.24.0+ |
| NEXT\_PUBLIC\_ROLLUP\_L1\_BASE\_URL                  | `string`                                                                                                                 | Blockscout base URL for L1 network. **DEPRECATED** **`Use NEXT_PUBLIC_ROLLUP_PARENT_CHAIN instead`**                                                                                                                                                                                                         | Required                          | -             | `http://eth-goerli.blockscout.com`                             | v1.24.0+ |
| NEXT\_PUBLIC\_ROLLUP\_L2\_WITHDRAWAL\_URL            | `string`                                                                                                                 | URL for L2 -> L1 withdrawals (Optimistic stack only)                                                                                                                                                                                                                                                         | Required for `optimistic` rollups | -             | `https://app.optimism.io/bridge/withdraw`                      | v1.24.0+ |
| NEXT\_PUBLIC\_ROLLUP\_STAGE\_INDEX                   | `"1" \| "2"`                                                                                                             | Reflects the maturity and decentralization level of the chain based on [L2BEAT's framework](https://medium.com/l2beat/introducing-stages-a-framework-to-evaluate-rollups-maturity-d290bb22befe). The label will be added to the sidebar according to the provided stage index. Not applicable for testnets.  | -                                 | -             | `"1"`                                                          | v2.1.0+  |
| NEXT\_PUBLIC\_FAULT\_PROOF\_ENABLED                  | `boolean`                                                                                                                | Set to `true` for chains with fault proof system enabled (Optimistic stack only)                                                                                                                                                                                                                             | -                                 | -             | `true`                                                         | v1.31.0+ |
| NEXT\_PUBLIC\_HAS\_MUD\_FRAMEWORK                    | `boolean`                                                                                                                | Set to `true` for instances that use MUD framework (Optimistic stack only)                                                                                                                                                                                                                                   | -                                 | -             | `true`                                                         | v1.33.0+ |
| NEXT\_PUBLIC\_INTEROP\_ENABLED                       | `boolean`                                                                                                                | Enables "Interop messages" page (Optimistic stack only)                                                                                                                                                                                                                                                      | -                                 | `false`       | `true`                                                         | v1.39.0+ |
| NEXT\_PUBLIC\_ROLLUP\_HOMEPAGE\_SHOW\_LATEST\_BLOCKS | `boolean`                                                                                                                | Set to `true` to display "Latest blocks" widget instead of "Latest batches" on the home page                                                                                                                                                                                                                 | -                                 | -             | `true`                                                         | v1.36.0+ |
| NEXT\_PUBLIC\_ROLLUP\_OUTPUT\_ROOTS\_ENABLED         | `boolean`                                                                                                                | Enables "Output roots" page (Optimistic stack only)                                                                                                                                                                                                                                                          | -                                 | `false`       | `true`                                                         | v1.37.0+ |
| NEXT\_PUBLIC\_ROLLUP\_PARENT\_CHAIN\_NAME            | `string`                                                                                                                 | Set to customize L1 transaction status labels in the UI (e.g., "Sent to "). This setting is applicable only for Arbitrum-based chains. **DEPRECATED** **`Use NEXT_PUBLIC_ROLLUP_PARENT_CHAIN instead`**                                                                                                      | -                                 | -             | `DuckChain`                                                    | v1.37.0+ |
| NEXT\_PUBLIC\_ROLLUP\_PARENT\_CHAIN                  | `ParentChain`, see details [below](/setup/env-variables/frontend-common-envs/envs#parent-chain-configuration-properties) | Configuration parameters for the parent chain.                                                                                                                                                                                                                                                               | -                                 | -             | `{"baseUrl":"https://explorer.duckchain.io"}`                  | v1.38.0+ |
| NEXT\_PUBLIC\_ROLLUP\_DA\_CELESTIA\_NAMESPACE        | `string`                                                                                                                 | Hex-string for creating a link to the transaction batch on the Seleneium explorer. "0x"-format and 60 symbol length. Available only for Arbitrum roll-ups.                                                                                                                                                   | -                                 | -             | `0x00000000000000000000000000000000000000ca1de12a9905be97beaf` | v1.38.0+ |
| NEXT\_PUBLIC\_ROLLUP\_DA\_CELESTIA\_CELENIUM\_URL    | `string`                                                                                                                 | URL for the Selenium explorer. It is used to create links to the Data Availability Blobs page. The URL should contain the full path without any search parameters related to the blob, as these will be constructed at runtime for each blob separately. Available only for Optimistic or Arbitrum roll-ups. | -                                 | -             | `https://mocha.celenium.io/blob`                               | v2.0.2+  |

#### Parent chain configuration properties

| Variable  | Type                                                  | Description                                                                                                                                                                    | Compulsoriness | Default value | Example value                                |
| --------- | ----------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------- | ------------- | -------------------------------------------- |
| id        | `number`                                              | Chain id, see [https://chainlist.org](https://chainlist.org) for the reference.                                                                                                | -              | -             | `42`                                         |
| name      | `string`                                              | Displayed name of the chain. Set to customize L1 transaction status labels in the UI (e.g., "Sent to "). Currently, this setting is applicable only for Arbitrum-based chains. | -              | -             | `DuckChain`                                  |
| baseUrl   | `string`                                              | Base url of the chain explorer.                                                                                                                                                | Required       | -             | `https://explorer.duckchain.io`              |
| rpcUrls   | `Array‹string›`                                       | Chain public RPC server urls, see [https://chainlist.org](https://chainlist.org) for the reference.                                                                            | -              | -             | `["https://rpc.duckchain.io"]`               |
| currency  | `{ name: string; symbol: string; decimals: number; }` | Chain currency config.                                                                                                                                                         | -              | -             | `{ name: Quack, symbol: QUA, decimals: 18 }` |
| isTestnet | `boolean`                                             | Set to true if network is testnet.                                                                                                                                             | -              | -             | `true`                                       |

### Export data to CSV file

| Variable                                  | Type     | Description                                                                                                                   | Compulsoriness | Default value | Example value   | Version |
| ----------------------------------------- | -------- | ----------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------- | ------- |
| NEXT\_PUBLIC\_RE\_CAPTCHA\_APP\_SITE\_KEY | `string` | See [below](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#google-recaptcha) | true           | -             | `<your-secret>` | v1.0.x+ |

### Google analytics

| Variable                                      | Type     | Description                                                               | Compulsoriness | Default value | Example value | Version |
| --------------------------------------------- | -------- | ------------------------------------------------------------------------- | -------------- | ------------- | ------------- | ------- |
| NEXT\_PUBLIC\_GOOGLE\_ANALYTICS\_PROPERTY\_ID | `string` | Property ID for [Google Analytics](https://analytics.google.com/) service | true           | -             | `UA-XXXXXX-X` | v1.0.x+ |

### Mixpanel analytics

| Variable                               | Type     | Description                                                           | Compulsoriness | Default value | Example value   | Version |
| -------------------------------------- | -------- | --------------------------------------------------------------------- | -------------- | ------------- | --------------- | ------- |
| NEXT\_PUBLIC\_MIXPANEL\_PROJECT\_TOKEN | `string` | Project token for [Mixpanel](https://mixpanel.com/) analytics service | true           | -             | `<your-secret>` | v1.1.0+ |

### GrowthBook feature flagging and A/B testing

| Variable                                | Type     | Description                                                         | Compulsoriness | Default value | Example value   | Version  |
| --------------------------------------- | -------- | ------------------------------------------------------------------- | -------------- | ------------- | --------------- | -------- |
| NEXT\_PUBLIC\_GROWTH\_BOOK\_CLIENT\_KEY | `string` | Client SDK key for [GrowthBook](https://www.growthbook.io/) service | true           | -             | `<your-secret>` | v1.22.0+ |

### GraphQL API documentation

This feature is **always enabled**, but you can disable it by passing `none` value to `NEXT_PUBLIC_GRAPHIQL_TRANSACTION` variable.

| Variable                            | Type     | Description                                                                                | Compulsoriness | Default value | Example value                                                        | Version |
| ----------------------------------- | -------- | ------------------------------------------------------------------------------------------ | -------------- | ------------- | -------------------------------------------------------------------- | ------- |
| NEXT\_PUBLIC\_GRAPHIQL\_TRANSACTION | `string` | Txn hash for default query at GraphQl playground page. Pass `none` to disable the feature. | -              | -             | `0x4a0ed8ddf751a7cb5297f827699117b0f6d21a0b2907594d300dc9fed75c7e62` | v1.0.x+ |

### REST API documentation

This feature is **always enabled**, but you can disable it by passing `none` value to `NEXT_PUBLIC_API_SPEC_URL` variable.

| Variable                     | Type     | Description                                                                   | Compulsoriness | Default value                                                                              | Example value                                                                              | Version |
| ---------------------------- | -------- | ----------------------------------------------------------------------------- | -------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------ | ------- |
| NEXT\_PUBLIC\_API\_SPEC\_URL | `string` | Spec to be displayed on `/api-docs` page. Pass `none` to disable the feature. | -              | `https://raw.githubusercontent.com/blockscout/blockscout-api-v2-swagger/main/swagger.yaml` | `https://raw.githubusercontent.com/blockscout/blockscout-api-v2-swagger/main/swagger.yaml` | v1.0.x+ |

### Marketplace

| Variable                                              | Type      | Description                                                                                                                                                                                                                                                                                                                        | Compulsoriness | Default value | Example value                                                   | Version  |
| ----------------------------------------------------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_MARKETPLACE\_ENABLED                    | `boolean` | `true` means that the marketplace page will be enabled                                                                                                                                                                                                                                                                             | Required       | -             | `true`                                                          | v1.24.1+ |
| NEXT\_PUBLIC\_MARKETPLACE\_CONFIG\_URL                | `string`  | URL of configuration file (`.json` format only) which contains list of apps that will be shown on the marketplace page. See [below](/setup/env-variables/frontend-common-envs/envs#marketplace-app-configuration-properties) list of available properties for an app. Can be replaced with NEXT\_PUBLIC\_ADMIN\_SERVICE\_API\_HOST | Required       | -             | `https://example.com/marketplace_config.json`                   | v1.0.x+  |
| NEXT\_PUBLIC\_ADMIN\_SERVICE\_API\_HOST               | `string`  | Admin Service API endpoint url. Can be used instead of NEXT\_PUBLIC\_MARKETPLACE\_CONFIG\_URL                                                                                                                                                                                                                                      | -              | -             | `https://admin-rs.services.blockscout.com`                      | v1.1.0+  |
| NEXT\_PUBLIC\_MARKETPLACE\_SUBMIT\_FORM               | `string`  | Link to form where authors can submit their dapps to the marketplace                                                                                                                                                                                                                                                               | Required       | -             | `https://airtable.com/shrqUAcjgGJ4jU88C`                        | v1.0.x+  |
| NEXT\_PUBLIC\_MARKETPLACE\_SUGGEST\_IDEAS\_FORM       | `string`  | Link to form where users can suggest ideas for the marketplace                                                                                                                                                                                                                                                                     | -              | -             | `https://airtable.com/appiy5yijZpMMSKjT/pag3t82DUCyhGRZZO/form` | v1.24.0+ |
| NEXT\_PUBLIC\_NETWORK\_RPC\_URL                       | `string`  | See in [Blockchain parameters](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-parameters) section                                                                                                                                                                      | Required       | -             | `https://core.poa.network`                                      | v1.0.x+  |
| NEXT\_PUBLIC\_MARKETPLACE\_CATEGORIES\_URL            | `string`  | URL of configuration file (`.json` format only) which contains the list of categories to be displayed on the marketplace page in the specified order. If no URL is provided, then the list of categories will be compiled based on the `categories` fields from the marketplace (apps) configuration file                          | -              | -             | `https://example.com/marketplace_categories.json`               | v1.23.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_SECURITY\_REPORTS\_URL     | `string`  | URL of configuration file (`.json` format only) which contains app security reports for displaying security scores on the Marketplace page                                                                                                                                                                                         | -              | -             | `https://example.com/marketplace_security_reports.json`         | v1.28.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_FEATURED\_APP              | `string`  | ID of the featured application to be displayed on the banner on the Marketplace page                                                                                                                                                                                                                                               | -              | -             | `uniswap`                                                       | v1.29.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_BANNER\_CONTENT\_URL       | `string`  | URL of the banner HTML content                                                                                                                                                                                                                                                                                                     | -              | -             | `https://example.com/banner`                                    | v1.29.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_BANNER\_LINK\_URL          | `string`  | URL of the page the banner leads to                                                                                                                                                                                                                                                                                                | -              | -             | `https://example.com`                                           | v1.29.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_RATING\_AIRTABLE\_API\_KEY | `string`  | Airtable API key                                                                                                                                                                                                                                                                                                                   | -              | -             | -                                                               | v1.33.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_RATING\_AIRTABLE\_BASE\_ID | `string`  | Airtable base ID with dapp ratings                                                                                                                                                                                                                                                                                                 | -              | -             | -                                                               | v1.33.0+ |
| NEXT\_PUBLIC\_MARKETPLACE\_GRAPH\_LINKS\_URL          | `string`  | URL of the file (`.json` format only) which contains the list of The Graph links to be displayed on the Marketplace page                                                                                                                                                                                                           | -              | -             | `https://example.com/graph_links.json`                          | v1.36.0+ |

#### Marketplace app configuration properties

| Property         | Type            | Description                                                                                  | Compulsoriness | Example value                       |
| ---------------- | --------------- | -------------------------------------------------------------------------------------------- | -------------- | ----------------------------------- |
| id               | `string`        | Used as slug for the app. Must be unique in the app list.                                    | Required       | `app`                               |
| external         | `boolean`       | `true` means that the application opens in a new window, but not in an iframe.               | -              | `true`                              |
| title            | `string`        | Displayed title of the app.                                                                  | Required       | `The App`                           |
| logo             | `string`        | URL to logo file. Should be at least 288x288.                                                | Required       | `https://foo.app/icon.png`          |
| shortDescription | `string`        | Displayed only in the app list.                                                              | Required       | `Awesome app`                       |
| categories       | `Array‹string›` | Displayed category.                                                                          | Required       | `[Security, Tools]`                 |
| author           | `string`        | Displayed author of the app                                                                  | Required       | `Bob`                               |
| url              | `string`        | URL of the app which will be launched in the iframe.                                         | Required       | `https://foo.app/launch`            |
| description      | `string`        | Displayed only in the modal dialog with additional info about the app.                       | Required       | `The best app`                      |
| site             | `string`        | Displayed site link                                                                          | -              | `https://blockscout.com`            |
| twitter          | `string`        | Displayed twitter link                                                                       | -              | `https://twitter.com/blockscoutcom` |
| telegram         | `string`        | Displayed telegram link                                                                      | -              | `https://t.me/poa_network`          |
| github           | `string`        | Displayed github link                                                                        | -              | `https://github.com/blockscout`     |
| internalWallet   | `boolean`       | `true` means that the application can automatically connect to the Blockscout wallet.        | -              | `true`                              |
| priority         | `number`        | The higher the priority, the higher the app will appear in the list on the Marketplace page. | -              | `7`                                 |

### Solidity to UML diagrams

| Variable                                 | Type     | Description                              | Compulsoriness | Default value | Example value                                | Version  |
| ---------------------------------------- | -------- | ---------------------------------------- | -------------- | ------------- | -------------------------------------------- | -------- |
| NEXT\_PUBLIC\_VISUALIZE\_API\_HOST       | `string` | Visualize API endpoint url               | Required       | -             | `https://visualizer.services.blockscout.com` | v1.0.x+  |
| NEXT\_PUBLIC\_VISUALIZE\_API\_BASE\_PATH | `string` | Base path for Visualize API endpoint url | -              | -             | `/poa/core`                                  | v1.29.0+ |

### Blockchain statistics

| Variable                             | Type     | Description                          | Compulsoriness | Default value | Example value                           | Version  |
| ------------------------------------ | -------- | ------------------------------------ | -------------- | ------------- | --------------------------------------- | -------- |
| NEXT\_PUBLIC\_STATS\_API\_HOST       | `string` | Stats API endpoint url               | Required       | -             | `https://stats.services.blockscout.com` | v1.0.x+  |
| NEXT\_PUBLIC\_STATS\_API\_BASE\_PATH | `string` | Base path for Stats API endpoint url | -              | -             | `/poa/core`                             | v1.29.0+ |

### Web3 wallet integration (add token or network to the wallet)

This feature is **enabled by default** with the `[metamask]` value. To switch it off pass `NEXT_PUBLIC_WEB3_WALLETS=none`.

| Variable                                            | Type                                                | Description                                                                                                                            | Compulsoriness | Default value    | Example value    | Version  |
| --------------------------------------------------- | --------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ---------------- | ---------------- | -------- |
| NEXT\_PUBLIC\_WEB3\_WALLETS                         | `Array‹"metamask" \| "coinbase" \| "token_pocket"›` | Array of Web3 wallets which will be used to add tokens or chain to. The first wallet which is enabled in user's browser will be shown. | -              | `[ "metamask" ]` | `[ "coinbase" ]` | v1.10.0+ |
| NEXT\_PUBLIC\_WEB3\_DISABLE\_ADD\_TOKEN\_TO\_WALLET | `boolean`                                           | Set to `true` to hide icon "Add to your wallet" next to token addresses                                                                | -              | -                | `true`           | v1.0.x+  |

### Transaction interpretation

| Variable                                            | Type                                | Description                                                                              | Compulsoriness | Default value | Example value | Version  |
| --------------------------------------------------- | ----------------------------------- | ---------------------------------------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_TRANSACTION\_INTERPRETATION\_PROVIDER | `"blockscout" \| "noves" \| "none"` | Transaction interpretation provider that displays human readable transaction description | -              | `none`        | `blockscout`  | v1.21.0+ |

### External transactions

| Variable                                         | Type                                                                             | Description                                                                                       | Compulsoriness | Default value | Example value                                                                                                                               | Version  |
| ------------------------------------------------ | -------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_TX\_EXTERNAL\_TRANSACTIONS\_CONFIG | `{ chain_name: string; chain_logo_url: string; explorer_url_template: string; }` | Configuration of the external transactions links that should be added to the transaction details. | -              | -             | `{ "chain_name": "ethereum", "chain_logo_url": "https://example.com/logo.png", "explorer_url_template": "https://explorer.com/tx/{hash}" }` | v1.38.0+ |

### Verified tokens info

| Variable                                | Type     | Description                    | Compulsoriness | Default value | Example value                                    | Version |
| --------------------------------------- | -------- | ------------------------------ | -------------- | ------------- | ------------------------------------------------ | ------- |
| NEXT\_PUBLIC\_CONTRACT\_INFO\_API\_HOST | `string` | Contract Info API endpoint url | Required       | -             | `https://contracts-info.services.blockscout.com` | v1.0.x+ |

### Name service integration

This feature allows resolving blockchain addresses using human-readable domain names.

| Variable                               | Type     | Description                   | Compulsoriness | Default value | Example value                          | Version  |
| -------------------------------------- | -------- | ----------------------------- | -------------- | ------------- | -------------------------------------- | -------- |
| NEXT\_PUBLIC\_NAME\_SERVICE\_API\_HOST | `string` | Name Service API endpoint url | Required       | -             | `https://bens.services.blockscout.com` | v1.22.0+ |

### Metadata service integration

This feature allows name tags and other public tags for addresses.

| Variable                                   | Type     | Description                       | Compulsoriness | Default value | Example value                              | Version  |
| ------------------------------------------ | -------- | --------------------------------- | -------------- | ------------- | ------------------------------------------ | -------- |
| NEXT\_PUBLIC\_METADATA\_SERVICE\_API\_HOST | `string` | Metadata Service API endpoint url | Required       | -             | `https://metadata.services.blockscout.com` | v1.30.0+ |

### Public tag submission

This feature allows you to submit an application with a public address tag.

| Variable                                   | Type     | Description                                                                                                                   | Compulsoriness | Default value | Example value                              | Version  |
| ------------------------------------------ | -------- | ----------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------ | -------- |
| NEXT\_PUBLIC\_METADATA\_SERVICE\_API\_HOST | `string` | Metadata Service API endpoint url                                                                                             | Required       | -             | `https://metadata.services.blockscout.com` | v1.30.0+ |
| NEXT\_PUBLIC\_ADMIN\_SERVICE\_API\_HOST    | `string` | Admin Service API endpoint url                                                                                                | Required       | -             | `https://admin-rs.services.blockscout.com` | v1.1.0+  |
| NEXT\_PUBLIC\_RE\_CAPTCHA\_APP\_SITE\_KEY  | `string` | See [below](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#google-recaptcha) | true           | -             | `<your-secret>`                            | v1.0.x+  |

### Data Availability

This feature enables views related to blob transactions (EIP-4844), such as the Blob Txns tab on the Transactions page and the Blob details page.

| Variable                                  | Type      | Description                                    | Compulsoriness | Default value | Example value | Version  |
| ----------------------------------------- | --------- | ---------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_DATA\_AVAILABILITY\_ENABLED | `boolean` | Set to true to enable blob transactions views. | Required       | -             | `true`        | v1.28.0+ |

### Bridged tokens

This feature allows users to view tokens that have been bridged from other EVM chains. Additional tab "Bridged" will be added to the tokens page and the link to original token will be displayed on the token page.

| Variable                               | Type                                                                                                                                                                              | Description                                                                                                                                  | Compulsoriness | Default value | Example value                                                                                       | Version  |
| -------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_BRIDGED\_TOKENS\_CHAINS  | `Array‹BridgedTokenChain›` where `BridgedTokenChain` can have following [properties](/setup/env-variables/frontend-common-envs/envs#bridged-token-chain-configuration-properties) | Used for displaying filter by the chain from which token where bridged. Also, used for creating links to original tokens in other explorers. | Required       | -             | `[{"id":"1","title":"Ethereum","short_title":"ETH","base_url":"https://eth.blockscout.com/token"}]` | v1.14.0+ |
| NEXT\_PUBLIC\_BRIDGED\_TOKENS\_BRIDGES | `Array‹TokenBridge›` where `TokenBridge` can have following [properties](/setup/env-variables/frontend-common-envs/envs#token-bridge-configuration-properties)                    | Used for displaying text about bridges types on the tokens page.                                                                             | Required       | -             | `[{"type":"omni","title":"OmniBridge","short_title":"OMNI"}]`                                       | v1.14.0+ |

#### Bridged token chain configuration properties

| Variable     | Type     | Description                                                                         | Compulsoriness | Default value | Example value                      |
| ------------ | -------- | ----------------------------------------------------------------------------------- | -------------- | ------------- | ---------------------------------- |
| id           | `string` | Base chain id, see [https://chainlist.org](https://chainlist.org) for the reference | Required       | -             | `1`                                |
| title        | `string` | Displayed name of the chain                                                         | Required       | -             | `Ethereum`                         |
| short\_title | `string` | Used for displaying chain name in the list view as tag                              | Required       | -             | `ETH`                              |
| base\_url    | `string` | Base url to original token in base chain explorer                                   | Required       | -             | `https://eth.blockscout.com/token` |

*Note* The url to original token will be constructed as `<base_url>/<token_hash>`, e.g `https://eth.blockscout.com/token/<token_hash>`

#### Token bridge configuration properties

| Variable     | Type     | Description                                                           | Compulsoriness | Default value | Example value |
| ------------ | -------- | --------------------------------------------------------------------- | -------------- | ------------- | ------------- |
| type         | `string` | Bridge type; should be matched to `bridge_type` field in API response | Required       | -             | `omni`        |
| title        | `string` | Bridge title                                                          | Required       | -             | `OmniBridge`  |
| short\_title | `string` | Bridge short title for displaying in the tags                         | Required       | -             | `OMNI`        |

### SafeCore address tags

For the smart contract addresses which are [Safe accounts](https://safe.global/) public tag "Multisig: Safe" will be displayed in the address page header alongside to Safe logo.

| Variable                             | Type     | Description                                                                                                                    | Compulsoriness | Default value | Example value | Version  |
| ------------------------------------ | -------- | ------------------------------------------------------------------------------------------------------------------------------ | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_SAFE\_TX\_SERVICE\_URL | `string` | The Safe transaction service URL. See full list of supported networks [here](https://docs.safe.global/api-supported-networks). | -              | -             | `uniswap`     | v1.26.0+ |

### Address profile API

This feature allows the integration of an external API to fetch user info for addresses or contracts. When configured, if the API returns a username, a public tag with a custom link will be displayed in the address page header.

| Variable                             | Type                                                                                                           | Description                                                                                                                                              | Compulsoriness | Default value | Example value | Version  |
| ------------------------------------ | -------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_ADDRESS\_USERNAME\_TAG | `{api_url: string; tag_link_template: string; tag_icon: string; tag_bg_color: string; tag_text_color: string}` | Address profile API tag configuration properties. See [below](/setup/env-variables/frontend-common-envs/envs#user-profile-api-configuration-properties). | -              | -             | `uniswap`     | v1.35.0+ |

#### Address profile API configuration properties

| Variable            | Type     | Description                                                                                          | Compulsoriness | Default value | Example value                       |
| ------------------- | -------- | ---------------------------------------------------------------------------------------------------- | -------------- | ------------- | ----------------------------------- |
| api\_url\_template  | `string` | User profile API URL. Should be a template with `{address}` variable                                 | Required       | -             | `https://example-api.com/{address}` |
| tag\_link\_template | `string` | External link to the profile. Should be a template with `{username}` variable                        | -              | -             | `https://example.com/{address}`     |
| tag\_icon           | `string` | Public tag icon (.svg) url                                                                           | -              | -             | `https://example.com/icon.svg`      |
| tag\_bg\_color      | `string` | Public tag background color (escape "#" symbol if you use HEX color codes or use rgba-value instead) | -              | -             | `\\#000000`                         |
| tag\_text\_color    | `string` | Public tag text color (escape "#" symbol if you use HEX color codes or use rgba-value instead)       | -              | -             | `\\#FFFFFF`                         |

### Address XStar XHS score

This feature allows the integration of an XStar API to fetch XHS score for addresses. When configured, if the API returns a score, a public tag with that score will be displayed in the address page header.

| Variable                        | Type     | Description                                                                             | Compulsoriness | Default value | Example value                                                                                        | Version  |
| ------------------------------- | -------- | --------------------------------------------------------------------------------------- | -------------- | ------------- | ---------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_XSTAR\_SCORE\_URL | `string` | XStar XHS score documentation URL for the address tag. Enables the XStar score feature. | -              | -             | `https://docs.xname.app/the-solution-adaptive-proof-of-humanity-on-blockchain/xhs-scoring-algorithm` | v1.36.0+ |

### SUAVE chain

For blockchains that implement SUAVE architecture additional fields will be shown on the transaction page ("Allowed peekers", "Kettle"). Users also will be able to see the list of all transactions for a particular Kettle in the separate view.

| Variable                       | Type      | Description                                                                                                          | Compulsoriness | Default value | Example value | Version  |
| ------------------------------ | --------- | -------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_IS\_SUAVE\_CHAIN | `boolean` | Set to true for blockchains with [SUAVE architecture](https://writings.flashbots.net/mevm-suave-centauri-and-beyond) | Required       | -             | `true`        | v1.14.0+ |

### Celo chain

For blockchains that use the Celo platform. *Note*, that once the Celo mainnet becomes an L2 chain, these variables will be migrated to the Rollup configuration section.

| Variable                               | Type      | Description                                                                                                                                              | Compulsoriness | Default value | Example value | Version  |
| -------------------------------------- | --------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_CELO\_ENABLED            | `boolean` | Indicates that it is a Celo-based chain.                                                                                                                 | -              | -             | `true`        | v1.37.0+ |
| NEXT\_PUBLIC\_CELO\_L2\_UPGRADE\_BLOCK | `number`  | Indicates the block number when the Celo-type chain transitioned to L2. This is used to display links to the Epoch block page from a regular block page. | -              | -             | `26369280`    | v1.37.0+ |

### Ton Application Chain (TAC)

For Ton Application Chains, this feature enables additional views, such as a list of cross-chain operations and a detailed page for a specific cross-chain operation, as well as extra fields on the transaction page.

| Variable                                           | Type     | Description                                                                                                | Compulsoriness | Default value | Example value                                    | Version |
| -------------------------------------------------- | -------- | ---------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------------ | ------- |
| NEXT\_PUBLIC\_TAC\_OPERATION\_LIFECYCLE\_API\_HOST | `string` | URL for the TAC Operation Lifecycle service.                                                               | Required       | -             | `https://tac-operation-lifecycle.blockscout.com` | v2.1.0+ |
| NEXT\_PUBLIC\_TAC\_TON\_EXPLORER\_URL              | `string` | URL of the Ton chain explorer. This is used to build links to transactions and addresses on the Ton chain. | Required       | -             | `https://tonscan.org`                            | v2.1.0+ |

### MetaSuites extension

Enables [MetaSuites browser extension](https://github.com/blocksecteam/metasuites) to integrate with the app views.

| Variable                          | Type      | Description                       | Compulsoriness | Default value | Example value | Version  |
| --------------------------------- | --------- | --------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_METASUITES\_ENABLED | `boolean` | Set to true to enable integration | Required       | -             | `true`        | v1.26.0+ |

### Validators list

The feature enables the Validators page which provides detailed information about the validators of the PoS chains.

| Variable                              | Type                                      | Description | Compulsoriness | Default value | Example value | Version  |
| ------------------------------------- | ----------------------------------------- | ----------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_VALIDATORS\_CHAIN\_TYPE | `"stability" \| "blackfort" \| "zilliqa"` | Chain type  | Required       | -             | `"stability"` | v1.25.0+ |

### Sentry error monitoring

*Note* This feature is **deprecated**. All ENV variables will be removed in the future releases.

| Variable                              | Type      | Description                                             | Compulsoriness | Default value | Example value   | Version  |
| ------------------------------------- | --------- | ------------------------------------------------------- | -------------- | ------------- | --------------- | -------- |
| NEXT\_PUBLIC\_SENTRY\_DSN             | `string`  | Client key for your Sentry.io app                       | Required       | -             | `<your-secret>` | v1.0.x+  |
| SENTRY\_CSP\_REPORT\_URI              | `string`  | URL for sending CSP-reports to your Sentry.io app       | -              | -             | `<your-secret>` | v1.0.x+  |
| NEXT\_PUBLIC\_SENTRY\_ENABLE\_TRACING | `boolean` | Enables tracing and performance monitoring in Sentry.io | -              | `false`       | `true`          | v1.17.0+ |

### Rollbar error monitoring

| Variable                             | Type     | Description                           | Compulsoriness | Default value | Example value   | Version  |
| ------------------------------------ | -------- | ------------------------------------- | -------------- | ------------- | --------------- | -------- |
| NEXT\_PUBLIC\_ROLLBAR\_CLIENT\_TOKEN | `string` | Client token for your Rollbar project | Required       | -             | `<your-secret>` | v1.37.x+ |

### OpenTelemetry

OpenTelemetry SDK for Node.js app could be enabled by passing `OTEL_SDK_ENABLED=true` variable. Configure the OpenTelemetry Protocol Exporter by using the generic environment variables described in the [OT docs](https://opentelemetry.io/docs/specs/otel/protocol/exporter/#configuration-options). Note that this Next.js feature is currently experimental. The Docker image should be built with the `NEXT_OPEN_TELEMETRY_ENABLED=true` argument to enable it.

| Variable           | Type      | Description                         | Compulsoriness | Default value | Example value | Version  |
| ------------------ | --------- | ----------------------------------- | -------------- | ------------- | ------------- | -------- |
| OTEL\_SDK\_ENABLED | `boolean` | Run-time flag to enable the feature | Required       | `false`       | `true`        | v1.18.0+ |

### DeFi dropdown

If the feature is enabled, a single button or a dropdown (if more than 1 item is provided) will be displayed at the top of the explorer page, which will take a user to the specified application in the marketplace or to an external site.

| Variable                            | Type                                                              | Description                                                                                                 | Compulsoriness | Default value | Example value                                                                                                                 | Version  |
| ----------------------------------- | ----------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------- | -------------- | ------------- | ----------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_DEFI\_DROPDOWN\_ITEMS | `[{ text: string; icon: string; dappId?: string, url?: string }]` | An array of dropdown items containing the button text, icon name and dappId in DAppscout or an external url | -              | -             | `[{"text":"Swap","icon":"swap","dappId":"uniswap"},{"text":"Payment link","icon":"payment_link","dappId":"peanut-protocol"}]` | v1.31.0+ |

### Multichain balance button

If the feature is enabled, a Multichain balance button will be displayed on the address page, which will take you to the portfolio application in the marketplace or to an external site.

| Variable                                            | Type                                                                       | Description                                                                                                                                    | Compulsoriness | Default value | Example value                                                                                                               | Version  |
| --------------------------------------------------- | -------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | --------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_MULTICHAIN\_BALANCE\_PROVIDER\_CONFIG | `[{ name: string; url_template: string; dapp_id?: string; logo: string }]` | Multichain portfolio application config See [below](/setup/env-variables/frontend-common-envs/envs#multichain-button-configuration-properties) | -              | -             | `[{ "name": "zerion", "url_template": "https://app.zerion.io/{address}/overview", "logo": "https://example.com/icon.svg"}]` | v1.31.0+ |

#### Multichain button configuration properties

| Variable      | Type     | Description                                                                                 | Compulsoriness | Default value | Example value                              |
| ------------- | -------- | ------------------------------------------------------------------------------------------- | -------------- | ------------- | ------------------------------------------ |
| name          | `string` | Multichain portfolio application name                                                       | Required       | -             | `zerion`                                   |
| url\_template | `string` | Url template to the portfolio. Should be a template with `{address}` variable               | Required       | -             | `https://app.zerion.io/{address}/overview` |
| dapp\_id      | `string` | Set for open a Blockscout dapp page with the portfolio instead of opening external app page | -              | -             | `zerion`                                   |
| logo          | `string` | Multichain portfolio application logo (.svg) url                                            | -              | -             | `https://example.com/icon.svg`             |

### Get gas button

If the feature is enabled, a Get gas button will be displayed in the top bar, which will take you to the gas refuel application in the marketplace or to an external site.

| Variable                                    | Type                                                                      | Description                                                                                                                | Compulsoriness | Default value | Example value                                                                                                                                                  | Version  |
| ------------------------------------------- | ------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------- |
| NEXT\_PUBLIC\_GAS\_REFUEL\_PROVIDER\_CONFIG | `{ name: string; url_template: string; dapp_id?: string; logo?: string }` | Get gas button config. See [below](/setup/env-variables/frontend-common-envs/envs#get-gas-button-configuration-properties) | -              | -             | `{ "name": "Need gas?", "dapp_id": "smol-refuel", "url_template": "https://smolrefuel.com/?outboundChain={chainId}", "logo": "https://example.com/icon.png" }` | v1.33.0+ |

#### Get gas button configuration properties

| Variable      | Type     | Description                                                              | Compulsoriness | Default value | Example value                                     |
| ------------- | -------- | ------------------------------------------------------------------------ | -------------- | ------------- | ------------------------------------------------- |
| name          | `string` | Text on the button                                                       | Required       | -             | `Need gas?`                                       |
| url\_template | `string` | Url template, may contain `{chainId}` variable                           | Required       | -             | `https://smolrefuel.com/?outboundChain={chainId}` |
| dapp\_id      | `string` | Set for open a Blockscout dapp page instead of opening external app page | -              | -             | `smol-refuel`                                     |
| logo          | `string` | Gas refuel application logo url                                          | -              | -             | `https://example.com/icon.png`                    |

### Save on gas with GasHawk

The feature enables a "Save with GasHawk" button next to the "Gas used" value on the address page.

| Variable                             | Type      | Description                         | Compulsoriness | Default value | Example value | Version  |
| ------------------------------------ | --------- | ----------------------------------- | -------------- | ------------- | ------------- | -------- |
| NEXT\_PUBLIC\_SAVE\_ON\_GAS\_ENABLED | `boolean` | Set to "true" to enable the feature | -              | -             | `true`        | v1.35.0+ |

### Rewards service API

This feature enables Blockscout Merits program. It requires that the [My account](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#my-account) and [Blockchain interaction](https://github.com/blockscout/docs/blob/master/setup/env-variables/frontend-common-envs/ENVS.md#blockchain-interaction-writing-to-contract-etc) features are also enabled.

| Variable                                  | Type     | Description | Compulsoriness | Default value | Example value         | Version  |
| ----------------------------------------- | -------- | ----------- | -------------- | ------------- | --------------------- | -------- |
| NEXT\_PUBLIC\_REWARDS\_SERVICE\_API\_HOST | `string` | API URL     | -              | -             | `https://example.com` | v1.36.0+ |

### DEX pools

| Variable                                | Type      | Description                       | Compulsoriness | Default value | Example value                                    | Version  |
| --------------------------------------- | --------- | --------------------------------- | -------------- | ------------- | ------------------------------------------------ | -------- |
| NEXT\_PUBLIC\_DEX\_POOLS\_ENABLED       | `boolean` | Set to true to enable the feature | Required       | -             | `true`                                           | v1.37.0+ |
| NEXT\_PUBLIC\_CONTRACT\_INFO\_API\_HOST | `string`  | Contract Info API endpoint url    | Required       | -             | `https://contracts-info.services.blockscout.com` | v1.0.x+  |

### Badge claim link

| Variable                               | Type     | Description                                    | Compulsoriness | Default value | Example value         | Version  |
| -------------------------------------- | -------- | ---------------------------------------------- | -------------- | ------------- | --------------------- | -------- |
| NEXT\_PUBLIC\_GAME\_BADGE\_CLAIM\_LINK | `string` | Provide to enable the easter egg badge feature | -              | -             | `https://example.com` | v1.37.0+ |

## External services configuration

### Google ReCaptcha

To obtain the variable values, please refer to the [reCAPTCHA documentation](https://developers.google.com/recaptcha) and check the [Blockscout reCAPTCHA config docs](https://docs.blockscout.com/setup/configuration-options/recaptcha). Please note that we currently support only **reCAPTCHA v2 in invisible mode**, read more [here](https://developers.google.com/recaptcha/docs/versions#recaptcha_v2_invisible_recaptcha_badge).

| Variable                                      | Type     | Description                                 | Compulsoriness | Default value | Example value     | Version |
| --------------------------------------------- | -------- | ------------------------------------------- | -------------- | ------------- | ----------------- | ------- |
| NEXT\_PUBLIC\_RE\_CAPTCHA\_V3\_APP\_SITE\_KEY | `string` | **DEPRECATED** Google reCAPTCHA v3 site key | -              | -             | `<your-secret>`   | v1.36.x |
| NEXT\_PUBLIC\_RE\_CAPTCHA\_APP\_SITE\_KEY     | `string` | Google reCAPTCHA v2 site key                | -              | -             | `<your-site-key>` | v1.0.x+ |


# Indexing
Source: https://docs.blockscout.com/setup/indexing

Indexing process, monitoring, and troubleshooting for Blockscout.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

BlockScout can take some time to fully index a chain. Larger chains require more time. Indexing starts from the head of the chain (the current block) and goes backwards towards the genesis block. The genesis block is the final block indexed during this process.

### Messages during indexing

1. **n% Blocks Indexed - We're indexing this chain right now. Some of the counts may be inaccurate.** This means blocks are still being collected and processed by BlockScout. The message should disappear once the genesis block is indexed.
2. **Blocks With Internal Transactions Indexed - We're indexing this chain right now. Some of the counts may be inaccurate.** This means BlockScout has collected all blocks but is still indexing internal transactions using the archive node tracing api. This message will disappear when `INDEXER_DISABLE_INTERNAL_TRANSACTIONS_FETCHER=true` is provided.

### Monitoring indexing processes

#### Monitoring blocks/transactions indexing

1. Block count should be close to the number of the blocks in the chain. Query using `SELECT COUNT(1) FROM blocks;` \~= num of blocks in the chain.
2. The number of missing blocks in the chain can be monitored with this query:

```sql theme={null}
SELECT COUNT(DISTINCT b1.number)
FROM generate_series(0, (SELECT MAX(number) FROM blocks)) AS b1(number)
WHERE NOT EXISTS (
    SELECT 1 FROM blocks b2 WHERE b2.number=b1.number AND b2.consensus
);
```

#### Monitoring internal transactions indexing

Internal transaction fetching can be monitored with this query: `SELECT COUNT(1) FROM pending_block_operations;` It should move towards zero during internal transaction processing.


# How Do I Fix Indexer Timeouts?
Source: https://docs.blockscout.com/setup/indexing/how-do-i-fix-indexer-timeouts



BlockScout utilizes two separate indexers in order to index the network history as well as keep up with new incoming blocks. Due to this process, a node may become overloaded and not respond to BlockScout's RPC requests within the designated timeout period.

The indexer umbrella application can be tweaked to meet your node's size and responsiveness. Outlined below are the locations and adjustments that can be made to each fetcher.

Fetchers are available at [https://github.com/blockscout/blockscout/tree/master/apps/indexer/lib/indexer/fetcher](https://github.com/blockscout/blockscout/tree/master/apps/indexer/lib/indexer/fetcher)

| Fetcher                                                                                                                                                                                       | Description                                                                                                                                                                                             | Batch size                                      | Concurrency                                      |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------- | ------------------------------------------------ |
| [Catchup Block Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/block/catchup/fetcher.ex#L24)                         | This fetcher indexes blocks, transactions and receipts starting from the tip of the chain working backward to the Genesis block.                                                                        | 10 `INDEXER_CATCHUP_BLOCKS_BATCH_SIZE`          | 10 `INDEXER_CATCHUP_BLOCKS_CONCURRENCY`          |
| [Transaction Receipts Fetcher](https://github.com/blockscout/blockscout/blob/4b272cf61dc14da76416be63f1f1df044b03a4b9/apps/indexer/lib/indexer/block/fetcher.ex#L85-L86)                      | Transaction receipts fetcher.                                                                                                                                                                           | 250 `INDEXER_RECEIPTS_BATCH_SIZE`               | 10 `INDEXER_RECEIPTS_CONCURRENCY`                |
| [Internal Transaction Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/internal_transaction/fetcher.ex#L20)           | This fetcher indexes internal transactions. For the real-time fetcher this process is done synchronously and for the catchup fetcher, this process is done asynchronously.                              | 10 `INDEXER_INTERNAL_TRANSACTIONS_BATCH_SIZE`   | 4 `INDEXER_INTERNAL_TRANSACTIONS_CONCURRENCY`    |
| [Coin Balance Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/coin_balance/fetcher.ex#L22)                           | This fetcher indexes each coin balance at the block height the address was interacted with.                                                                                                             | 100 `INDEXER_COIN_BALANCES_BATCH_SIZE`          | 4 `INDEXER_COIN_BALANCES_CONCURRENCY`            |
| [Uncle Block Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/block/uncle/fetcher.ex#L22)                             | This fetcher indexes non-consensus blocks, transactions, and receipts.                                                                                                                                  | 10                                              | 10                                               |
| [Token Balance Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/token_balance/fetcher.ex#L29)                         | This fetcher indexes token balances. Note you may experience some token balances that cannot be fetched due to a malformed smart contract or other functions that do not allow a balance to be fetched. | 100 `INDEXER_TOKEN_BALANCES_BATCH_SIZE`         | 10 `INDEXER_TOKEN_BALANCES_CONCURRENCY`          |
| [Token Fetcher](https://github.com/blockscout/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/indexer/lib/indexer/token/fetcher.ex#L18)                                         | This indexer fetches the metadata for a token contract                                                                                                                                                  | 1                                               | 10                                               |
| [Block Reward Fetcher](https://github.com/blockscout/blockscout/blob/4b272cf61dc14da76416be63f1f1df044b03a4b9/apps/indexer/lib/indexer/fetcher/block_reward.ex#L28-L29)                       | Block reward fetcher.                                                                                                                                                                                   | 10 `INDEXER_BLOCK_REWARD_BATCH_SIZE`            | 10 `INDEXER_BLOCK_REWARD_CONCURRENCY`            |
| [Token Instance Realtime Fetcher](https://github.com/blockscout/blockscout/blob/4b272cf61dc14da76416be63f1f1df044b03a4b9/apps/indexer/lib/indexer/fetcher/token_instance/realtime.ex#L16-L17) | Token instance realtime fetcher.                                                                                                                                                                        | 1 `INDEXER_TOKEN_INSTANCE_REALTIME_BATCH_SIZE`  | 10 `INDEXER_TOKEN_INSTANCE_REALTIME_CONCURRENCY` |
| [Token Instance Retry Fetcher](https://github.com/blockscout/blockscout/blob/4b272cf61dc14da76416be63f1f1df044b03a4b9/apps/indexer/lib/indexer/fetcher/token_instance/retry.ex#L16-L17)       | Token instance retry fetcher.                                                                                                                                                                           | 10 `INDEXER_TOKEN_INSTANCE_RETRY_CONCURRENCY`   | 10 `INDEXER_TOKEN_INSTANCE_RETRY_BATCH_SIZE`     |
| [Token Instance Sanitize Fetcher](https://github.com/blockscout/blockscout/blob/4b272cf61dc14da76416be63f1f1df044b03a4b9/apps/indexer/lib/indexer/fetcher/token_instance/sanitize.ex#L16-L17) | Token instance sanitize fetcher.                                                                                                                                                                        | 10 `INDEXER_TOKEN_INSTANCE_SANITIZE_BATCH_SIZE` | 10 `INDEXER_TOKEN_INSTANCE_SANITIZE_CONCURRENCY` |

## Understanding Errors and Timeouts

`application=indexer fetcher=coin_balance count=500 error_count=500 [error] failed to fetch: :timeout`

In the error provided above, we can tell that the **indexer** application failed to fetch **500** **coin balances** due to a **timeout** error. Usually, when an indexer starts to receive timeouts, many more timeouts from other fetchers will occur as well.

### Resolving Timeout Issues

The best action to take when fetchers start to receive timeouts is to lower the batch size and concurrency of a few fetchers which will put less pressure on the node.

The two indexers that cause the most strain to the node are the block fetcher and the internal transactions fetcher. It would be advised to cut these fetchers values in half and restart the application. A restart of the node may also be required.

### Other Actions

BlockScout comes equipped with functionality to automatically stop sending requests for `n` seconds if timeouts are detected. You may adjust these settings by setting a different value for `wait_per_timeout`.

[https://github.com/poanetwork/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/ethereum\_jsonrpc/config/config.exs#L3-L9](https://github.com/poanetwork/blockscout/blob/1475e3bfd002d9397efd0f0cc29c20f39a70d023/apps/ethereum_jsonrpc/config/config.exs#L3-L9)

<Tip>
  Content moved from [https://forum.poa.network/t/faq-how-do-i-fix-indexer-timeouts/1829](https://forum.poa.network/t/faq-how-do-i-fix-indexer-timeouts/1829)
</Tip>


# How Do I Update Memory Consumption To Fix Indexer Memory Errors?
Source: https://docs.blockscout.com/setup/indexing/how-do-i-update-memory-consumption-to-fix-indexer-memory-errors



During the indexing phase, many fetching processes are run asynchronously due to the load placed on trying to fetch all of the block content at once. These processes are stored in memory to be fetched at set intervals defined in each asynchronous fetcher.

`Indexer.Memory.Monitor` checks if the BEAM memory usage exceeds a set limit (defaults to 1 GiB) and if it does, it asks the process with the most memory that is registered as shrinkable to shrink.

Memory usage is checked once per minute. If the soft-limit is reached, the shrinkable work queues will shed half their load. The shed load will be restored from the database, the same as when a restart of the server occurs, so rebuilding the work queue will be slower, but use less memory.

If all queues are at their minimum size, then no more memory can be reclaimed and an error will be logged.

### Future Work

As mentioned above, future work is entered into memory to be processed later. These same processes are imported into the database to be checked on a server restart and reentered into memory to be processed.

### Updating Memory Consumption

The default Memory limit is 1 GiB and can be edited by setting `INDEXER_MEMORY_LIMIT` environment variable. See [Memory Usage](/setup/configuration-options/memory-usage) for more info.

### Left Bitshift Conversion Table

To perform a left bitshift conversion yourself open the interactive shell.

1\. `iex`
2\. `import Bitwise`
3\. `1 <<< 30` //1073741824

|                                                            |                |             |       |
| ---------------------------------------------------------- | -------------- | ----------- | ----- |
| `INDEXER_MEMORY_LIMIT` environment variable value          | Left Bitshift  | Bytes       | GiB   |
| `1` or `1gb` or `1g` regardless of the case of the letters | `1 <<< 30`     | 1073741824  | 1     |
| `5` or `5gb` or `5g`                                       | `5 <<< 30`     | 5368709120  | 5.3   |
| `10` or `10gb` or `10g`                                    | `10 <<< 30`    | 10737418240 | 10.7  |
| `15` or `15gb` or `15g`                                    | `15 <<< 30`    | 16106127360 | 16.1  |
| `20` or `20gb` or `20g`                                    | `20 <<< 30`    | 21474836480 | 21.4  |
| `25` or `25gb` or `25g`                                    | `25 <<< 30`    | 26843545600 | 26.8  |
| `30` or `30gb` or `30g`                                    | `30 <<< 30`    | 32212254720 | 32.2  |
| `35` or `35gb` or `35g`                                    | `35 <<< 30`    | 37580963840 | 37.6  |
| `40` or `40gb` or `40g`                                    | `40 <<< 30`    | 42949672960 | 43    |
| `45` or `45gb` or `45g`                                    | `45 <<< 30`    | 48318382080 | 48.3  |
| `50` or `50gb` or `50g`                                    | `50 <<< 30`    | 53687091200 | 53.7  |
| `100mb` or `100m` regardless of the case of the letters    | `100 <<< 20`   | 104857600   | 0.105 |
| `500mb` or `500m`                                          | `500 <<< 20`   | 524288000   | 0.52  |
| `1500mb` or `1500m`                                        | `1500 <<< 20`  | 1572864000  | 1.57  |
| `9536mb` or `9536m`                                        | `9536 <<< 20`  | 9999220736  | \~10  |
| `28610mb` or `28610m`                                      | `28610 <<< 20` | 29999759360 | \~30  |


# General Overview
Source: https://docs.blockscout.com/setup/information-and-settings

General overview of Blockscout architecture and settings.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

The following pages detail Blockscout architecture and organization:

* [Indexer, Web App, API](/setup/information-and-settings/separate-indexer-web-app-and-api)

* [Umbrella Project Organization](/setup/information-and-settings/umbrella-project)

* [Indexer Architecture Overview](/setup/information-and-settings/indexer-architecture-overview)

* [ShareLock](/setup/information-and-settings/sharelock)

* [EVM Version Information](/setup/information-and-settings/evm-version-information)


# EVM Version Information
Source: https://docs.blockscout.com/setup/information-and-settings/evm-version-information



You are asked to provide the EVM version the contract uses during the verification process. If the bytecode does not match the version, we try to verify using the latest EVM version.

For more information, see the [Solidity docs on specifying the EVM version when compiling a contract](https://docs.soliditylang.org/en/v0.8.25/using-the-compiler.html#target-options). Note that backward compatibility is not guaranteed between each version.

|                             |              |                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| --------------------------- | ------------ | --------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Name                        | Date         | Mainnet Block #                                                                                                             | Relevant changes / opcode specs                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | EIP details                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Prague (Pectra)             | 07 May 2025  | Block [22,431,084](https://eth.blockscout.com/block/22431084) <br /><br />Epoch [364032](https://beaconcha.in/epoch/364032) | EIP-7702 enables externally owned accounts (EOAs) to temporarily execute smart contract code, allowing transaction batching, gas sponsorship, and alternative authentication methods. EIP-7251 raises maximum validator balance from 32 ETH to 2048 ETH for reward compounding. EIP-7691 doubles blob throughput (target: 3→6, max: 6→9 blobs per block) to enhance Layer 2 scaling. EIP-2537 adds BLS12-381 curve operations for efficient cryptographic verification. EIP-7002 enables execution layer triggerable validator exits. EIP-6110 reduces validator deposit processing delay from \~9 hours to \~13 minutes.                                              | • [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537)<br /><br />• [EIP-2935](https://eips.ethereum.org/EIPS/eip-2935)<br /><br />• [EIP-6110](https://eips.ethereum.org/EIPS/eip-6110)<br /><br />• [EIP-7002](https://eips.ethereum.org/EIPS/eip-7002)<br /><br />• [EIP-7251](https://eips.ethereum.org/EIPS/eip-7251)<br /><br />• [EIP-7549](https://eips.ethereum.org/EIPS/eip-7549)<br /><br />• [EIP-7623](https://eips.ethereum.org/EIPS/eip-7623)<br /><br />• [EIP-7685](https://eips.ethereum.org/EIPS/eip-7685)<br /><br />• [EIP-7691](https://eips.ethereum.org/EIPS/eip-7691)<br /><br />• [EIP-7702](https://eips.ethereum.org/EIPS/eip-7702)<br /><br />• [EIP-7840](https://eips.ethereum.org/EIPS/eip-7840) |
| Cancun                      | 13 Mar 2024  | [19,426,587](https://eth.blockscout.com/block/19426587)                                                                     | The block's blob base fee ([EIP-7516](https://eips.ethereum.org/EIPS/eip-7516) and [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844)) can be accessed via the global `block.blobbasefee` or `blobbasefee()` in inline assembly. Introduces `blobhash()` in inline assembly and a corresponding global function to retrieve versioned hashes of blobs associated with the transaction (see [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844)). Opcode `mcopy` is available in assembly (see [EIP-5656](https://eips.ethereum.org/EIPS/eip-5656)). Opcodes `tstore` and `tload` are available in assembly (see [EIP-1153](https://eips.ethereum.org/EIPS/eip-1153)). | • [EIP-1153](https://eips.ethereum.org/EIPS/eip-1153)<br /><br />• [EIP-4788](https://eips.ethereum.org/EIPS/eip-4788)<br /><br />• [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844)<br /><br />• [EIP-5656](https://eips.ethereum.org/EIPS/eip-5656)<br /><br />• [EIP-6780](https://eips.ethereum.org/EIPS/eip-6780)<br /><br />• [EIP-7516](https://eips.ethereum.org/EIPS/eip-7516)                                                                                                                                                                                                                                                                                                                                      |
| Shanghai                    | 12 Apr 2023  | [17,034,870](https://eth.blockscout.com/block/17034870)                                                                     | Smaller code size and gas savings due to the introduction of `push0` (see [EIP-3855](https://eips.ethereum.org/EIPS/eip-3855)).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | • [EIP-3651](https://eips.ethereum.org/EIPS/eip-3651)<br /><br />• [EIP-3855](https://eips.ethereum.org/EIPS/eip-3855)<br /><br />• [EIP-3860](https://eips.ethereum.org/EIPS/eip-3860)<br /><br />• [EIP-4895](https://eips.ethereum.org/EIPS/eip-4895)<br /><br />• [EIP-6049](https://eips.ethereum.org/EIPS/eip-6049)                                                                                                                                                                                                                                                                                                                                                                                                       |
| Paris (The Merge)           | 15 Sep 2022  | [15,537,394](https://eth.blockscout.com/block/15537394)                                                                     | Introduces `prevrandao()` and `block.prevrandao`, and changes the semantics of the now deprecated `block.difficulty`, disallowing `difficulty()` in inline assembly (see [EIP-4399](https://eips.ethereum.org/EIPS/eip-4399)).                                                                                                                                                                                                                                                                                                                                                                                                                                         | • [EIP-3675](https://eips.ethereum.org/EIPS/eip-3675) <br /><br />• [EIP-4399](https://eips.ethereum.org/EIPS/eip-4399)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| *Gray Glacier\**            | 30 June 2022 | [15,050,000](https://eth.blockscout.com/block/15050000)                                                                     | Delays the difficulty bomb by an additional 3 months to September 2022.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | [https://eips.ethereum.org/EIPS/eip-5133](https://eips.ethereum.org/EIPS/eip-5133)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| *Arrow Glacier\**           | 09 Aug 2021  | [13,773,000](https://eth.blockscout.com/block/13773000)                                                                     | Delays the difficulty bomb until June 2022.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | [https://eips.ethereum.org/EIPS/eip-4345](https://eips.ethereum.org/EIPS/eip-4345)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| London                      | 05 Aug 2021  | [12,965,000](https://eth.blockscout.com/block/12965000)                                                                     | The block's base fee ([EIP-3198](https://eips.ethereum.org/EIPS/eip-3198) and [EIP-1559](https://eips.ethereum.org/EIPS/eip-1559)) can be accessed via the global `block.basefee` or `basefee()` in inline assembly.                                                                                                                                                                                                                                                                                                                                                                                                                                                   | • [EIP-1559](https://eips.ethereum.org/EIPS/eip-1559)<br /><br />• [EIP-3198](https://eips.ethereum.org/EIPS/eip-3198)<br /><br />• [EIP-3529](https://eips.ethereum.org/EIPS/eip-3529)<br /><br />• [EIP-3541](https://eips.ethereum.org/EIPS/eip-3541)<br /><br />• [EIP-3554](https://eips.ethereum.org/EIPS/eip-3554)                                                                                                                                                                                                                                                                                                                                                                                                       |
| Berlin                      | 14 Apr 2021  | [12,244,000](https://eth.blockscout.com/block/12244000)                                                                     | Gas costs for `SLOAD`, `*CALL`, `BALANCE`, `EXT*` and `SELFDESTRUCT` increased. The compiler assumes cold gas costs for such operations. This is relevant for gas estimation and the optimizer.                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | [https://eips.ethereum.org/EIPS/eip-2070](https://eips.ethereum.org/EIPS/eip-2070)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Istanbul                    | 08 Dec 2019  | [9,069,000](https://eth.blockscout.com/block/9069000)                                                                       | Opcodes `chainid` and `selfbalance` are available in assembly.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | [https://eips.ethereum.org/EIPS/eip-1679](https://eips.ethereum.org/EIPS/eip-1679)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Constantinople / Petersburg | 28 Feb 2019  | [7,280,000](https://eth.blockscout.com/block/7280000)                                                                       | Opcodes `create2`, `extcodehash`, `shl`, `shr` and `sar` are available in assembly. Bitwise shifting operators use shifting opcodes (`shl`,`shr`,`sar`), requiring less gas.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | [http://eips.ethereum.org/EIPS/eip-1013](http://eips.ethereum.org/EIPS/eip-1013)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Byzantium                   | 16 Oct 2017  | [4,370,000](https://eth.blockscout.com/block/4370000)                                                                       | Opcodes `returndatacopy`, `returndatasize` and `staticcall` available in assembly. `staticcall` opcode used when calling non-library view or pure functions, which prevents the functions from modifying state at the EVM level, this even applies to invalid type conversions. Ability to access dynamic data returned from function calls. `revert` opcode introduced, `revert()` will not waste gas.                                                                                                                                                                                                                                                                | [http://eips.ethereum.org/EIPS/eip-609](http://eips.ethereum.org/EIPS/eip-609)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Spurious Dragon             | 22 Nov 2016  | [2,675,000](https://eth.blockscout.com/block/2675000)                                                                       | Gas cost for the `exp` opcode increased, impacts gas estimation and optimization.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | [http://eips.ethereum.org/EIPS/eip-607](http://eips.ethereum.org/EIPS/eip-607)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Tangerine Whistle           | 18 Oct 2016  | [2,463,000](https://eth.blockscout.com/block/2463000)                                                                       | Gas cost to access other accounts increased, impacts gas estimation and optimization. All gas sent by default for external calls, previously a certain amount had to be retained.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | [http://eips.ethereum.org/EIPS/eip-608](http://eips.ethereum.org/EIPS/eip-608)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Homestead                   | 14 Mar 2016  | [1,150,000](https://eth.blockscout.com/block/1150000)                                                                       | Oldest version                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | [http://eips.ethereum.org/EIPS/eip-606](http://eips.ethereum.org/EIPS/eip-606)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |


# Indexer Architecture Overview
Source: https://docs.blockscout.com/setup/information-and-settings/indexer-architecture-overview

Learn how the indexing architecture works in Blockscout

<Frame>
  <img alt="" />
</Frame>

## Presentation Highlights

The following presentation describes the past, present and future iterations of Blockscout along with details about how block imports work both synchronously and asynchronously, and a description of the regular and on-demand fetchers.

<Card title="Blockscout Indexer Architecture Overview.pdf" icon="file-pdf" href="https://blockscout-icons.s3.us-east-1.amazonaws.com/Blockscout+Indexer+Architecture+Overview.pdf">
  1MB pdf
</Card>

## Blockscout indexers

See the pdf ⬆️ for more details about the Blockscout indexer. The indexing architecture includes all of the following indexers and fetchers

### Primary Indexers

Both indexers utilize synchronous and asynchronous operations.

* Realtime: Imports new block data from the head of the chain.
* Catchup: Imports data down the chain (starting from the head and moving backwards towards the genesis block)

### Secondary fetchers

### Regular

* Internal transactions
* Pending transactions
* Dropped/Replaced transactions
* Contract bytecodes
* Block rewards
* Token catalog
* Token/coin balances
* NFT instances
* Uncles

### On Demand

* Coin/token balances update
* Contract bytecodes fetch/re-check
* Contract source codes lookup
* NFT instance metadata re-fetch
* Token total supply

### Off-chain integrations

* Coin / token price, market cap, tvl sources: CMC, Coingecko, Cryptorank, Defillama
* Smart contract verification: ETH bytecode DB, Sourcify
* Data enrichment: ENS names, public tags, AI interpreters (own, Noves Fi), sc security scanners (Solidityscan), assets portfolio (Zerion)
* Chain initialization data import: pre-mined coins, precompiled smart-contracts

### Chain-specific fetchers

* There are more than a dozen of chain-specific data fetchers to account for chain differences including arbitrum, optimism, polygon zkevm, zksync etc.

### Temporary fetchers

* Used once to resolve possible data inconsistencies.


# Separate Indexer, Web App, And API
Source: https://docs.blockscout.com/setup/information-and-settings/separate-indexer-web-app-and-api



Blockscout supports several modes which run in a single all-in-one application by default.

**Modes**

* [Indexer](/setup/information-and-settings/separate-indexer-web-app-and-api#indexer-mode)

* [Web UI](/setup/information-and-settings/separate-indexer-web-app-and-api#web-application-mode)

* [API](/setup/information-and-settings/separate-indexer-web-app-and-api#api-mode)

* All-in-one (default)

It is possible to run modes separately or in different combinations. For example, you may want to run the `indexer mode + API` to create an indexed db with programmatic access and no UI, or `indexer mode + UI` to leverage Blockscout as a read-only explorer.

Note that the application is limited to 1 running indexer per 1 Blockscout instance. However, the indexer automatically reruns child processes within the Elixir architecture, making it quite fault-tolerant.

To run these modes separately, adjust ENV variables as follows:

<Info>
  After extending the set of environment variables for the instance, recompile the application (or rebuilt the docker image, if this is Docker version) to enable mode settings.
</Info>

## Indexer mode

To run Blockscout in indexer mode, disable the web application and API:

```javascript theme={null}
export DISABLE_WEBAPP=true
export API_V1_READ_METHODS_DISABLED=true
export API_V1_WRITE_METHODS_DISABLED=true
```

## Web application mode

To run Blockscout in web application mode only, disable the indexer and API read methods (API write functionality is not disabled to support smart contracts verification in the UI).

```javascript theme={null}
export DISABLE_INDEXER=true
export API_V1_READ_METHODS_DISABLED=true
```

<Info>
  If you have a separate web application and indexer and they are connected to the same database (via DATABASE\_URL), you will see new incoming items on the web UI like in the all-in-one mode. This configuration allows you to scale the web UI separately from indexer.
</Info>

## API mode

To run in API mode, disable the indexer and webapp.

```javascript theme={null}
export DISABLE_INDEXER=true
export DISABLE_WEBAPP=true
```

<Info>
  In API mode the web UI will show the API docs page at the default path (/). In the default all-in-one mode, it is located on the /api-docs page.
</Info>

## Web UI + API mode

```javascript theme={null}
export DISABLE_INDEXER=true
```


# ShareLock
Source: https://docs.blockscout.com/setup/information-and-settings/sharelock

ShareLock is the row-level locking mechanism used internally by PostgreSQL.

### Deadlocks and prevention

When several DB transactions are acting on multiple rows of the same table, it's possible to incur in a deadlock and so into an error. This can be prevented by enforcing the same consistent order of lock acquisition on *all* the transactions performing `INSERT`, `UPDATE` or `DELETE` on a given table.

On top of this, if multiple DB transactions act on multiple tables a deadlock will occur, even if they follow the order on each table described above, if they acquire locks on said tables in a different order. This can also be prevented by using a consistent order of lock acquisition *between* different tables.

### Imposing the lock acquisition order on a table with Ecto

When `INSERT`ing a list of rows Postgres will respect the order in which they appear in the query, so the reordering can happen beforehand.

For example, this will work:

```python theme={null}
entries = [...]

ordered_entries = Enum.sort_by(entries, & &1.id)

Repo.insert_all(__MODULE__, ordered_entries)
```

Performing `UPDATE`s is trickier because there is no `ORDER BY` clause. The solution to this is to `JOIN` on a subquery that `SELECT`s with the option `FOR UPDATE`.

Using Ecto this can be done, for example, like this:

```csharp theme={null}
query =
  from(
    entry in Entry,
    where: not is_nil(entry.value),
    order_by: entry.id,
    lock: "FOR UPDATE"
  )

Repo.update_all(
  from(e in Entry, join: s in subquery(query), on: e.id == s.id),
  [set: [value: nil]],
  timeout: timeout)
```

`DELETE` has the same quirks as `UPDATE` and it is too solved in the same way.

For example:

```csharp theme={null}
query =
  from(
    entry in Entry,
    where: is_nil(entry.value),
    order_by: entry.id,
    lock: "FOR UPDATE"
  )

Repo.delete_all(from(e in Entry, join: s in subquery(query), on: e.id == s.id))
```

### Imposing the lock acquisition order between tables with Ecto

When using an `Ecto.Multi` to perform `INSERT`, `UPDATE` or `DELETE` on multiple tables the order to keep is between different operation. For example, supposing `EntryA` was established to be modified before `EntryB`, this is not correct:

```ruby theme={null}
Multi.new()
|> Multi.run(:update_b, fn repo, _ ->
  # operations with ordered locks on `EntryB`
end)
|> Multi.run(:update_a, fn repo, _ ->
  # operations with ordered locks on `EntryA`
end)
|> Repo.transaction()
```

When possible, the simple solution is to move `:update_a` to be before `:update_b`. When not possible, for instance if `:update_a` depends on the result of `:update_b`, this can be solved by acquiring the locks in a separate operation.

For example:

```python theme={null}
Multi.new()
|> Multi.run(:acquire_a, fn repo, _ ->
  # acquire locks in order on `EntryA`
end)
|> Multi.run(:update_b, fn repo, _ ->
  # operations with ordered locks on `EntryB`
end)
|> Multi.run(:update_a, fn repo, %{acquire_a: values} ->
  # operations (no need to enforce order again) on `EntryA`
end)
|> Repo.transaction()
```

Note also that for the same reasons multiple operations on the same table in the same transaction are not safe to perform if they each acquire locks in order, because locks are not released until the transaction is committed.

### Order used for Explorer's tables

This is a complete list of the ordering currently in use on each table. It also specifies the order between tables in the same transaction: locks for a table on top need to be acquired before those from a table on the bottom.

Note that this should always be enforced because as long as there is one DB transaction performing in a different order there is the possibility of a deadlock.

| schema module                                     | table name                               | ordered by                                                                                                |
| ------------------------------------------------- | ---------------------------------------- | --------------------------------------------------------------------------------------------------------- |
| Explorer.Chain.Address                            | addresses                                | \[asc: :hash]                                                                                             |
| Explorer.Chain.Address.Name                       | address\_names                           | \[asc: :address\_hash, asc: :name]                                                                        |
| Explorer.Chain.Address.CoinBalance                | address\_coin\_balances                  | \[asc: :address\_hash, asc: :block\_number]                                                               |
| Explorer.Chain.Block                              | blocks                                   | \[asc: :hash]                                                                                             |
| Explorer.Chain.Block.SecondDegreeRelation         | block\_second\_degree\_relations         | \[asc: :nephew\_hash, asc: :uncle\_hash]                                                                  |
| Explorer.Chain.Block.Reward                       | block\_rewards                           | \[asc: :address\_hash, asc: :address\_type, asc: :block\_hash]                                            |
| Explorer.Chain.Block.EmissionReward               | emission\_rewards                        | \[asc: :block\_range]                                                                                     |
| Explorer.Chain.Transaction                        | transactions                             | \[asc: :hash]                                                                                             |
| Explorer.Chain.Transaction.Fork                   | transaction\_forks                       | \[asc: :uncle\_hash, asc: :index]                                                                         |
| Explorer.Chain.Log                                | logs                                     | \[asc: :transaction\_hash, asc: :index]                                                                   |
| Explorer.Chain.InternalTransaction                | internal\_transactions                   | \[asc: :transaction\_hash, asc: :index]                                                                   |
| Explorer.Chain.Token                              | tokens                                   | \[asc: :contract\_address\_hash]                                                                          |
| Explorer.Chain.TokenTransfer                      | token\_transfers                         | \[asc: :transaction\_hash, asc: :log\_index]                                                              |
| Explorer.Chain.TransactionAction                  | transaction\_actions                     | \[asc: :hash, asc: :log\_index]                                                                           |
| Explorer.Chain.Optimism.OutputRoot                | op\_output\_roots                        | \[asc: :l2\_output\_index]                                                                                |
| Explorer.Chain.Optimism.TxnBatch                  | op\_transaction\_batches                 | \[asc: :l2\_block\_number]                                                                                |
| Explorer.Chain.Optimism.Deposit                   | op\_deposits                             | \[asc: :l2\_transaction\_hash]                                                                            |
| Explorer.Chain.Optimism.DisputeGame               | op\_dispute\_games                       | \[asc: :index]                                                                                            |
| Explorer.Chain.Optimism.FrameSequence             | op\_frame\_sequences                     | \[asc: :id]                                                                                               |
| Explorer.Chain.Optimism.FrameSequenceBlob         | op\_frame\_sequence\_blobs               | \[asc: :id]                                                                                               |
| Explorer.Chain.Optimism.WithdrawalEvent           | op\_withdrawal\_events                   | \[asc: :withdrawal\_hash, asc: :l1\_event\_type]                                                          |
| Explorer.Chain.Optimism.Withdrawal                | op\_withdrawals                          | \[asc: :msg\_nonce]                                                                                       |
| Explorer.Chain.Optimism.EIP1559ConfigUpdate       | op\_eip1559\_config\_updates             | \[asc: :l2\_block\_number]                                                                                |
| Explorer.Chain.Optimism.InteropMessage            | op\_interop\_messages                    | \[asc: :nonce, asc: :init\_chain\_id]                                                                     |
| Explorer.Chain.Address.TokenBalance               | address\_token\_balances                 | \[asc: :address\_hash, asc: :token\_contract\_address\_hash, asc: :block\_number]                         |
| Explorer.Chain.Address.CurrentTokenBalance        | address\_current\_token\_balances        | \[asc: :token\_contract\_address\_hash, asc: :token\_id, asc: :address\_hash]                             |
| Explorer.Chain.Scroll.Batch                       | scroll\_batches                          | \[asc: number]                                                                                            |
| Explorer.Chain.Scroll.BatchBundle                 | scroll\_batch\_bundles                   | \[asc: final\_batch\_number]                                                                              |
| Explorer.Chain.Scroll.Bridge                      | scroll\_bridge                           | \[asc: :type, asc: message\_hash]                                                                         |
| Explorer.Chain.Scroll.L1FeeParam                  | scroll\_l1\_fee\_params                  | \[asc: :block\_number, asc: tx\_index, asc: name]                                                         |
| Explorer.Chain.Shibarium.Bridge                   | shibarium\_bridge                        | \[asc: :operation\_hash, asc: l1\_transaction\_hash, asc: l2\_transaction\_hash]                          |
| Explorer.Chain.StakingPool                        | staking\_pools                           | \[asc: :staking\_address\_hash]                                                                           |
| Explorer.Chain.StakingPoolsDelegator              | staking\_pools\_delegators               | \[asc: :delegator\_address\_hash, asc: :pool\_address\_hash]                                              |
| Explorer.Chain.ContractMethod                     | contract\_methods                        | \[asc: :identified, asc: :abi]                                                                            |
| Explorer.Market.MarketHistory                     | market\_history                          | \[asc: :date]                                                                                             |
| Explorer.Chain.Withdrawal                         | withdrawals                              | \[asc: :index]                                                                                            |
| Explorer.Chain.Zkevm.TransactionBatch             | zkevm\_transaction\_batches              | \[asc: :number]                                                                                           |
| Explorer.Chain.Zkevm.BatchTransaction             | zkevm\_batch\_l2\_transactions           | \[asc: :hash]                                                                                             |
| Explorer.Chain.Zkevm.LifecycleTransaction         | zkevm\_lifecycle\_l1\_transactions       | \[asc: :id]                                                                                               |
| Explorer.Chain.Zkevm.Bridge                       | zkevm\_bridge                            | \[asc: :type, asc: :index]                                                                                |
| Explorer.Chain.Zkevm.BridgeL1Token                | zkevm\_bridge\_l1\_tokens                | \[asc: :address]                                                                                          |
| Explorer.Chain.ZkSync.TransactionBatch            | zksync\_transaction\_batches             | \[asc: :number]                                                                                           |
| Explorer.Chain.ZkSync.BatchBlock                  | zksync\_batch\_blocks                    | \[asc: :hash]                                                                                             |
| Explorer.Chain.ZkSync.BatchTransaction            | zksync\_batch\_transactions              | \[asc: :hash]                                                                                             |
| Explorer.Chain.ZkSync.LifecycleTransaction        | zksync\_lifecycle\_transactions          | \[asc: :id]                                                                                               |
| Explorer.Chain.Celo.PendingAccountOperation       | celo\_pending\_account\_operations       | \[asc: :address\_hash]                                                                                    |
| Explorer.Chain.Celo.Account                       | celo\_accounts                           | \[asc: :address\_hash]                                                                                    |
| Explorer.Chain.Celo.ValidatorGroupVote            | celo\_validator\_group\_votes            | \[asc: :transaction\_hash, asc: :account\_address\_hash, asc: :group\_address\_hash]                      |
| Explorer.Chain.Celo.Epoch                         | celo\_epochs                             | \[asc: :number]                                                                                           |
| Explorer.Chain.Celo.EpochReward                   | celo\_epoch\_rewards                     | \[asc: :epoch\_number]                                                                                    |
| Explorer.Chain.Celo.ElectionReward                | celo\_election\_rewards                  | \[asc: :epoch\_number, asc: type, asc: :account\_address\_hash, asc: :associated\_account\_address\_hash] |
| Explorer.Chain.Zilliqa.QuorumCertificate          | zilliqa\_quorum\_certificates            | \[asc: :block\_hash]                                                                                      |
| Explorer.Chain.Zilliqa.AggregateQuorumCertificate | zilliqa\_aggregate\_quorum\_certificates | \[asc: :block\_hash]                                                                                      |
| Explorer.Chain.Zilliqa.NestedQuorumCertificate    | zilliqa\_nested\_quorum\_certificates    | \[asc: :block\_hash, asc: proposed\_by\_validator\_index]                                                 |
| Explorer.Chain.Zilliqa.Zrc2.TokenAdapter          | zilliqa\_zrc2\_token\_adapters           | \[asc: :adapter\_address\_hash]                                                                           |
| Explorer.Chain.Zilliqa.Zrc2.TokenTransfer         | zilliqa\_zrc2\_token\_transfers          | \[asc: :transaction\_hash, asc: :block\_hash, asc: :log\_index]                                           |
| Explorer.Chain.Filecoin.PendingAddressOperation   | filecoin\_pending\_address\_operations   | \[asc: :address\_hash]                                                                                    |


# Umbrella Project Organization
Source: https://docs.blockscout.com/setup/information-and-settings/umbrella-project

How the BlockScout project is organized

BlockScout is an Elixir [umbrella project](https://elixir-lang.org/getting-started/mix-otp/dependencies-and-umbrella-projects.html). Each directory under `apps/` is a separate [Mix](https://hexdocs.pm/mix/Mix.html) project and [OTP application](https://hexdocs.pm/elixir/Application.html), but the projects can use each other as a dependency in their `mix.exs`.

Each OTP application has a restricted domain.

<Info>
  Table is horizontally scrollable.
</Info>

|                         |                     |                   |                                                                                                                                                                                                                                                                                                                                                                          |
| ----------------------- | ------------------- | ----------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Directory               | OTP Application     | Namespace         | Purpose                                                                                                                                                                                                                                                                                                                                                                  |
| `apps/ethereum_jsonrpc` | `:ethereum_jsonrpc` | `EthereumJSONRPC` | Ethereum JSONRPC client. It is allowed to know `Explorer`'s param format, but it cannot directly depend on `:explorer`                                                                                                                                                                                                                                                   |
| `apps/explorer`         | `:explorer`         | `Explorer`        | Storage for the indexed chain. Can read and write to the backing storage. MUST be able to boot in a read-only mode when run independently from `:indexer`, so cannot depend on `:indexer` as that would start `:indexer` indexing.                                                                                                                                       |
| `apps/block_scout_web`  | `:block_scout_web`  | `BlockScoutWeb`   | Phoenix interface to `:explorer`. The minimum interface to allow web access should go in `:block_scout_web`. Any business rules or interface not tied directly to `Phoenix` or `Plug` should go in `:explorer`. MUST be able to boot in a read-only mode when run independently from `:indexer`, so cannot depend on `:indexer` as that would start `:indexer` indexing. |
| `apps/indexer`          | `:indexer`          | `Indexer`         | Uses `:ethereum_jsonrpc` to index chain and batch import data into `:explorer`. Any process, `Task`, or `GenServer` that automatically reads from the chain and writes to `:explorer` should be in `:indexer`. This restricts automatic writes to `:indexer` and read-only mode can be achieved by not running `:indexer`.                                               |


# Microservices
Source: https://docs.blockscout.com/setup/microservices

Overview of Blockscout microservices and their deployment.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

Blockscout microservices are individual components written in Rust designed to provide full functionality to the explorer. This architecture allows for better scalability, easier maintenance, and more flexible deployment options.

Information about Blockscout microservices and how to run them is available here:

Services Include:

1. [blockscout-ens](https://github.com/blockscout/blockscout-rs/blob/main/blockscout-ens) - indexed data of domain name service for blockscout instances.
2. [da-indexer](https://github.com/blockscout/blockscout-rs/blob/main/da-indexer) - collects blobs from different DA solutions (e.g, Celestia)
3. [eth-bytecode-db](https://github.com/blockscout/blockscout-rs/blob/main/eth-bytecode-db) - Ethereum Bytecode Database. Cross-chain smart-contracts database used for automatic contracts verification
4. [proxy-verifier](https://github.com/blockscout/blockscout-rs/blob/main/proxy-verifier) - backend for the standalone multi-chain verification service
5. [sig-provider](https://github.com/blockscout/blockscout-rs/blob/main/sig-provider) - aggregator of ethereum signatures for transactions and events
6. [smart-contract-verifier](https://github.com/blockscout/blockscout-rs/blob/main/smart-contract-verifier) - smart-contracts verification
7. [stats](https://github.com/blockscout/blockscout-rs/blob/main/stats) - service designed to calculate and present statistical information from a Blockscout instance
8. [user-ops-indexer](https://github.com/blockscout/blockscout-rs/blob/main/user-ops-indexer) - service designed to index, decode and serve user operations as per the ERC-4337 standard
9. [visualizer](https://github.com/blockscout/blockscout-rs/blob/main/visualizer) - service for evm visualization such as:

   a. Solidity contract visualization using [sol2uml](https://www.npmjs.com/package/sol2uml)


# Blockscout ENS (BENS) Name Service Integration
Source: https://docs.blockscout.com/setup/microservices/blockscout-ens-bens-name-service-integration

BENS service extends Blockscout support for name services

Blockscout now support Name Services for various chains including ENS for Ethereum. Search by name in the search bar or used the dedicated Name Services lookup page accessible from the Blockchain menu.

<Frame>
  <img />
</Frame>

On the Name Services page search by name or address and view registration and expiration date for all names.

## Adding Name Service Support

Protocols can add Name Service support for Blockscout instances on various chains. The BENS microservice was first introduced in [Blockscout v5.4](https://github.com/blockscout/blockscout/releases/tag/v5.4.0-beta), and several bugs were fixed in\*\* **[**Blockscout v6.0**](https://github.com/blockscout/blockscout/releases/tag/v6.0.0-beta)**, which is the recommended minimum version for integration.\*\*

You'll complete the following steps to add Name Service Support to Blockscout:

1. [Use this guide to create a subgraph](https://github.com/blockscout/blockscout-rs/blob/main/blockscout-ens/graph-node/subgraph-writer/README.md#howto-create-subgraph-for-your-domain-name-protocol). Our template uses the ENS subgraph structure, so the closer your project is the ENS the easier the integration.

   a. Subgraph should support [this graphql schema](https://github.com/blockscout/blockscout-rs/blob/main/blockscout-ens/graph-node/subgraphs/ens-subgraph/schema.graphql)

2. [Submit your subgraph](https://github.com/blockscout/blockscout-rs/blob/main/blockscout-ens/graph-node/subgraphs/README.md#deploy-subgraph-to-graph-node) to graph-node.

3. Submit a PR to the [blockscout-rs](https://github.com/blockscout/blockscout-rs/pulls) repository (hosted version) or integrate with your Blockscout fork.

   a. [Example PR for BNS](https://github.com/blockscout/blockscout-rs/pull/748) (Base Name Service)

4. Enable BENS service on the instance using the [`MICROSERVICE_BENS_ENABLED`](/setup/env-variables#blockscout-ens)` `& [`MICROSERVICE_BENS_URL`](/setup/env-variables#blockscout-ens) env variables.

### FAQs

<AccordionGroup>
  <Accordion title="Some domains are being indexed in a hashed format. What might cause this?">
    This may be the result of missing information/functions in the subgraph. When a subgraph sees that a domain name has been registered, it only has the `label_hash` of this name. Therefore, the subgraph has to guess the name using a rainbow table (make sure to load ens-rainbow table) OR find this name later in other events, such as `handleNameChanged` or any other event that has a name field.

    Try to determine events with a name field, write code that will update domain name using `maybeSaveDomainName()` or other functions you prefer. For example, the ens-subgraph uses the `setNamePreimage` function, which performs the same function for second-level-eth domains only.

    **Reverse Records**

    It may also be the case that unknown names are reverse records. These are not resolved by design, and users don't typically need to see them.
  </Accordion>

  <Accordion title="How do I launch BENS locally?">
    The easiest way is to use docker.

    `docker run --platform linux/x86_64 -p 8050:8050 --rm --name bens --env-file .env `[`ghcr.io/blockscout/bens:latest`](http://ghcr.io/blockscout/bens:latest)

    To build locally without docker you should install `protoc` and `protoc-gen-openapiv2` . A complete guide for a local build is not yet available.
  </Accordion>

  <Accordion title="What does 'primary' refer to in the Domains dropdown in the Blockscout UI?">
    The primary name is the first name created which has not yet expired.

    <img alt="" />
  </Accordion>
</AccordionGroup>


# Smart Contract Verification
Source: https://docs.blockscout.com/setup/microservices/smart-contract-verification

Details about the verification microservice

A microservice written in Rust provides fast and efficient contract verification. The application runs as an HTTP server and verification requests are made using a REST API.

* [Basic Info](/setup/microservices/smart-contract-verification#basic-info)
* [Library Initialization](/setup/microservices/smart-contract-verification#library-initialization)
* [Solidity and Vyper Verification](/setup/microservices/smart-contract-verification#solidity-and-vyper-verification)
* [Sourcify Verification](/setup/microservices/smart-contract-verification#sourcify-verification)
* [Verification Algorithm](/setup/microservices/smart-contract-verification#verification-algorithm)
* [Http API](/setup/microservices/smart-contract-verification#verification-http-api)

## Basic Info

### **Location**

* Application: [https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier)
* Http API: [https://github.com/blockscout/blockscout-rs/blob/main/smart-contract-verifier/smart-contract-verifier-http](https://github.com/blockscout/blockscout-rs/blob/main/smart-contract-verifier/smart-contract-verifier-http/README.md)
* Latest release information and changelogs: [https://github.com/blockscout/blockscout-rs/releases](https://github.com/blockscout/blockscout-rs/releases)

### **Activation**

* Update Blockscout to the 4.1.8+ release
* Add the following ENV variables:
  * `MICROSERVICE_SC_VERIFIER_ENABLED=true`
  * `MICROSERVICE_SC_VERIFIER_URL=...` (verifier endpoint, see [http configuration](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier/smart-contract-verifier-http) for more details)
* If running locally, the smart-contract-verifier is integrated with [`docker-compose`](https://github.com/blockscout/blockscout/tree/master/docker-compose)\`\`
  * Registry of docker images is available via the docker-compose file. For registry information see: [https://github.com/blockscout/blockscout-rs/pkgs/container/smart-contract-verifier](https://github.com/blockscout/blockscout-rs/pkgs/container/smart-contract-verifier)

### Architecture

The service consists of 2 parts, a verification library and a transport layer that serves requests.

* **Verification Library**: Provides verification and a communication interface for verification functions. Includes modules for Solidity, Sourcify, and Vyper.
* **Transport Layer**: Verification requests are sent via HTTP.

### Benefits

We've seen a 10X improvement in verification speed over the previous implementation. Benefits of the new microservice include:

* **Scalability**: Remove CPU intensive tasks from the primary Blockscout instance. Modularity provides the ability to scale quickly.
* **Speed**: Using native compilers greatly increases compilation speed relative to the JS wrapped versions running on Node.js used previously.
* **Improved efficiency**. New algorithm supports contracts that contain several metadata hashes, improving efficiency.

## Library Initialization

On startup, the library must retrieve all available compilers. Compiler information consists of a link to download the compiler and its hashsum \[[example](https://github.com/blockscout/solc-bin/blob/main/list.json)]. A separate thread also starts during initialization to update this list periodically.

Library processes differ based on verification for Solidity/Vyper contracts or verification via Sourcify. Both are detailed below.

## Solidity and Vyper Verification

Verification processes are similar for contracts written in Solidity and Vyper.

For Solidity contracts, verification is available for multiple files or standard json input. Single file verification is also possible - users still verify via the multiple file method and only upload a single file.

For Vyper contracts, only multiple file verification is available.

### Request Values

Each request contains the following values:

* **Deployed bytecode**: bytecode of the contract stored on chain
* **Creation transaction (tx) input**: input data provided in transaction to create the contract
* **Compiler version**: Version of compiler used to compile the contract
* **Content**: Verification method related fields. E.g. for Solidity multiple files those fields are:
  * **Sources**: mapping from source files to their contents
  * **Evm version**: version of the EVM used to compile sources
  * **Optimization runs**: optional parameter that enables optimizations and specifies number of optimization runs
  * **Contract libraries**: optional parameter that specifies addresses of the contract libraries used in compiled contracts

### Verification Steps

1. **Download the compiler** using the specified compiler version from the url retrieved on [initialization](/setup/microservices/smart-contract-verification#initialization) (or update).
2. **Compilation**: compile using the provided and slightly modified (see [Verification Algorithm](/setup/microservices/smart-contract-verification#verification-algorithm) section) sources.
3. **Verification**: compare compiler output from step 2 with bytecodes (deployed bytecode and creation tx input) provided by the caller. During verification all contracts obtained through local compilation are checked one by one, and if any corresponds to provided bytecodes, the verification is considered successful. Contract paths and names are already indexed from available contracts, and constructor arguments are extracted.
4. **Return Values**: See below.

### Returned Values

As a result of successful verification the following struct is returned:

* **Compiler input**: Data used as an input for the compiler
* **Compiler version**: version of the compiler used in verification (corresponds to the version provided in request)
* **File path**: path of the file containing verified contract
* **Contract name**: name of the verified contract
* **Abi**: application binary interface of the verified contract ([https://docs.soliditylang.org/en/v0.8.13/abi-spec.html?highlight=abi](https://docs.soliditylang.org/en/v0.8.13/abi-spec.html?highlight=abi))
* **Constructor arguments**: optionally returned constructor arguments used during on chain creation of the contract.

In case of an error, enum is returned with the corresponding error and its description (e.g. if compilation failed, a Compilation error is returned with the error data obtained from the compiler).

## Sourcify Verification

The request is sent via proxy to the [Sourcify](https://sourcify.dev/) service. It accepts the following arguments:

1. Address of the contract to be verified.
2. Chain id where the contract is deployed.
3. Files required for Sourcify verification.
4. (optionally)Contract index, if the provided files contain multiple metadata files (i.e. multiple contracts).

These arguments are sent to the Sourcify Api, which returns the verification status.

### **Successful Verification**

Either the data provided was valid and the contract was verified by Sourcify, or the contract was previously verified. To obtain the actual data used for verification we send another request to retrieve source files used in verification. We expect data used for verification to be in the `metadata.json` file, so it is parsed and the information retrieved. This includes file and contract names, compiler and evm versions, info about optimizations, contract libraries, abi, and sources.

<Info>
  **Note**: Constructor arguments cannot currently be obtained from the metadata via Sourcify. This requires the input used for contract creation transaction and the bytecode resulting from local compilation, which are not provided.
</Info>

### Failed Verification

If verification fails we return an error with description obtained from Sourcify response

## Verification Algorithm

Verification is divided into 2 parts to effectively deal with metadata hash differences in contracts. Often, very similar contracts will have very different metadata hashes based on small changes within the contract (ie an extra space in the source code). To address this, the algorithm:

1. Extracts all metadata hash fields from c\_reationTxInput\_.
2. Compares non-metadata sections of the onchain bytecode with the results of local compilation.

Metadata hashes are extracted by compiling the same contract twice (with a slight modification to the 2nd contract that does not change any other aspect of the resultant bytecode). The resulting c\_reationTxInput\_s are compared and metadata hashes extracted by finding which parts of the inputs differ.

### Example

An additional space in the source code can be used for the modification process. In **Example 1** and **Example 2** the only difference between both contracts is a space in the beginning of **Example 2**. However, this still completely changes the metadata hash (metadata hash differences shown in **bold red**).

<Info>
  **Note**: To update the metadata hash in production we use an additional library passed into the compiler. It does not effect the resultant bytecode, but the compilation input is altered, leading to updated metadata and an updated metadata hash.
</Info>

#### Example 1

```javascript theme={null}
// pragma solidity ^0.8.7; contract Main {}
```

<Info>
  *creationTxInput:* 6080604052348015600f57600080fd5b50603f80601d6000396000f3fe6080604052600080fdfea264697066735822**12203cc19b771ee83d8cc6995191bd9092a82f3e66b95aacaf1cfc893d3dc27abcd2**64736f6c63430008070033
</Info>

#### Example 2

```javascript theme={null}
// pragma solidity ^0.8.7; contract Main {}
```

<Info>
  *creationTxInput:* 6080604052348015600f57600080fd5b50603f80601d6000396000f3fe6080604052600080fdfea264697066735822**1220b3902f5797f05bb62858c8d41f09402093c85957c4ae1d773e4eb1cb2000f093**64736f6c63430008070033
</Info>

### Verification Process

1. Compile the original contracts using data provided by the caller then compile those contracts again while passing in the additional library. The result is two slightly different `CreationTxInputs` if there is any encoded metadata.
2. Separate the `MainPart` and the `MetadataPart`.
   a. `MainPart` consists of consecutive bytes which are not related to the metadata hash (all bytes are the same for both local c\_reationTxInputs\_). `MetadataPart` consists of consecutive bytes related to metadata hash (some bytes differ between local c\_reationTxInputs\_).
3. Iterate through the two local contracts byte by byte to find the first byte that differs.
   a. If there are no such bytes, then there is no metadata hash and the whole *creationTxInput* consists of just one `MainPart`.
   b. If any differences are found, identify it as a hash section of the metadata hash.
   c. Iterate back byte by byte to find the beginning of that metadata hash. When we find the beginning we know where that metadata hash starts and ends. All non-categorized bytes before the start are identified as the `MainPart` and bytes between the start and end identified as the `MetadataPart`. Continue until there are no uncategorized bytes.
   d. Once the entire local *creationTxInput* is categorized, we compare those parts with the corresponding remote *creationTxInput* bytes. For the `MainPart` remote *creationTxInput* must have exact equivalence. For the `MetadataPart` we compare some parts of the metadata (e.g. that encoded solc versions are the same), but in general we do not require them to be equal.

**Example**

<Info>
  ***LocalCreationTxInput1:*** 608060405234801561001057600080fd5b506040518060200161002190610050565b6020820181038252601f19601f820116604052506000908051906020019061004a92919061005c565b5061015f565b605c806101ac83390190565b8280546100689061012e565b90600052602060002090601f01602090048101928261008a57600085556100d1565b82601f106100a357805160ff19168380011785556100d1565b828001600101855582156100d1579182015b828111156100d05782518255916020019190600101906100b5565b5b5090506100de91906100e2565b5090565b5b808211156100fb5760008160009055506001016100e3565b5090565b7f4e487b7100000000000000000000000000000000000000000000000000000000600052602260045260246000fd5b6000600282049050600182168061014657607f821691505b602082108103610159576101586100ff565b5b50919050565b603f8061016d6000396000f3fe6080604052600080fdfea2646970667358221220187a584947e37ebca43172929f7e159fe28696b0edd97bbfad5b0a265f6f886964736f6c634300080e00336080604052348015600f57600080fd5b50603f80601d6000396000f3fe6080604052600080fdfea2646970667358221220805aa9fe4ec055702024afa5ac21c2104f0b14be0ffab086f0d6e9b5701073f864736f6c634300080e0033

  **Parts 1:** \`\`\[ MainPart(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), MetadataPart(a264697066735822**1220187a584947e37ebca43172929f7e159fe28696b0edd97bbfad5b0a265f6f8869**64736f6c634300080e0033), MainPart(6080604052348015600f57600080fd5b50603f80601d6000396000f3fe6080604052600080fdfe), MetadataPart(a264697066735822**1220805aa9fe4ec055702024afa5ac21c2104f0b14be0ffab086f0d6e9b5701073f8**64736f6c634300080e0033) ]

  ***LocalCreationTxInput2:*** 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

  **Parts 2:**

  \[ MainPart(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),

  MetadataPart(a264697066735822**12202e82fb6222f966f0e56dc49cd1fb8a6b5eac9bdf74f62b8a5e9d8812901095d6**64736f6c634300080e0033),

  MainPart(6080604052348015600f57600080fd5b50603f80601d6000396000f3fe6080604052600080fdfe),

  MetadataPart(a264697066735822**1220bd9f7fd5fb164e10dd86ccc9880d27a177e74ba873e6a9b97b6c4d7062b26ff0**64736f6c634300080e0033)

  ]
</Info>

#### Constructor arguments

Constructor arguments are extracted at the end of the verification process. Constructor arguments are appended at the end of the *creationTxInput* returned by the compiler. So, to extract these arguments we remove parts presented in local *creationTxInput*, and consider everything else as likely constructor arguments.

After that we attempt to map potential constructor args to the constructor abi of the contract. If successful, extracted args are returned as actual constructor arguments.

## Verification Http Api

Currently, verification requests are sent via HTTP requests. This module runs an HTTP server and provides endpoints through which external services (main Blockscout instance, in our case) send verification requests and receive responses. Endpoints provided by the service and configuration details are described in the [corresponding Readme file](https://github.com/blockscout/blockscout-rs/tree/main/smart-contract-verifier-http).

<Info>
  Currently only synchronous endpoints are available. In the future a new service that handles asynchronous requests on top of the current smart-contract-verifier may be implemented.
</Info>


# Requirements
Source: https://docs.blockscout.com/setup/requirements

System, hardware, and software requirements for running Blockscout.

<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

See the submenu for requirements information

* [General requirements and software dependencies](/setup/requirements/requirements)

* [Hardware and hosting requirements](/setup/requirements/resource-requirements)

* [DB storage requirements](/setup/requirements/database-storage-requirements)

* [Client setting requirements](/setup/requirements/client-settings) (Geth, Erigon, Nethermind etc)

* [Node Tracing Requirements](/setup/requirements/node-tracing-json-rpc-requirements) by Client


# Backend/Frontend Compatibility Matrix
Source: https://docs.blockscout.com/setup/requirements/back-front-compatibility-matrix



| frontend/backend | v9.3.x | v9.2.x | v9.1.x | v9.0.x | v8.1.x | v8.0.x | v7.0.x | v6.10.x | v6.9.x | v6.8.x | v6.7.x | v6.6.x | v6.5.x | v6.4.x | v6.3.x | v6.2.x | v6.1.x | v6.0.x | v5.4.x | v5.3.x | v5.2.x | v5.1.x | v5.0.x |
| ---------------- | :----- | :----- | :----- | :----- | ------ | ------ | ------ | ------- | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ |
| v2.5.x           | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.4.x           | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.3.1+          | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.3.0           | ❌      | ✅      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.2.x           | ❌      | ❌      | ❌      | ✅      | ✅      | ✅      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.1.x           | ❌      | ❌      | ❌      | ✅      | ✅      | ✅      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v2.0.x           | ❌      | ❌      | ❌      | ✅      | ✅      | ✅      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.38.1+         | ❌      | ❌      | ❌      | ✅      | ✅      | ✅      | ✅      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.37.6+         | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.37.5-         | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.36.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.35.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ✅      | ✅      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.34.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ✅      | ✅      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.33.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ✅      | ✅      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.32.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.31.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.30.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.29.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.28.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.27.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.26.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.25.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.24.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.23.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.22.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.21.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.20.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.19.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.18.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.17.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.16.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      | ❌      |
| v1.15.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.14.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.13.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.12.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.11.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.10.x          | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.9.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.8.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.7.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.6.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.5.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      | ❌      |
| v1.4.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      |
| v1.3.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      |
| v1.2.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      |
| v1.1.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ❌      | ❌      | ❌      |
| v1.0.x           | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌       | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ❌      | ✅      | ✅      | ✅      | ✅      |


# Client Setting Requirements
Source: https://docs.blockscout.com/setup/requirements/client-settings



<Tip>
  🚗 [Autoscout is now available](/using-blockscout/autoscout), providing a simple one-click explorer deployment with Blockscout's optimized hosting infrastructure. Use it for early testing, modifications, and launching a full production-grade explorer. [**Get Started Now**](/using-blockscout/autoscout) **and have your explorer up-and-running in minutes.**
</Tip>

## Supported JSON RPC Clients

BlockScout currently supports [Geth](https://github.com/ethereum/go-ethereum), [Erigon](https://github.com/erigontech/erigon), [Nethermind](https://github.com/NethermindEth/nethermind), [Reth](https://github.com/paradigmxyz/reth), [Besu](https://github.com/hyperledger/besu), [RSKj](https://github.com/rsksmart/rskj), [Lotus](https://github.com/filecoin-project/lotus), and [Anvil](https://book.getfoundry.sh/anvil/) JSON RPC clients. To define the JSON RPC node variant, it's advised to define the `ETHEREUM_JSONRPC_VARIANT` environment variable\*. Correct values include:

| JSON RPC Client | Value          | Note                                                                                        |
| --------------- | -------------- | ------------------------------------------------------------------------------------------- |
| Geth            | \`geth\`       | Default. This value is applicable for both Geth and Reth JSON RPC clients                   |
| Erigon          | \`erigon\`     | It is suggested to use `erigon` variant for Reth JSON RPC client.                           |
| Nethermind      | \`nethermind\` | This value is applicable for Reth and deprecated OpenEthereum (aka Parity) JSON RPC clients |
| Besu            | \`besu\`       |                                                                                             |
| RSKj            | \`rsk\`        |                                                                                             |
| Lotus           | \`filecoin\`   |                                                                                             |
| Anvil           | \`anvil\`      |                                                                                             |

\*If the variable is not set, JSON RPC variant will be chosen based on `CHAIN_TYPE` variable according to the mapping [https://github.com/blockscout/blockscout/blob/a2625803c831fb86e38ffe0e28d94bfd697914ce/apps/ethereum\_jsonrpc/lib/ethereum\_jsonrpc/variant.ex#L114-L120](https://github.com/blockscout/blockscout/blob/a2625803c831fb86e38ffe0e28d94bfd697914ce/apps/ethereum_jsonrpc/lib/ethereum_jsonrpc/variant.ex#L114-L120)

```ruby theme={null}
  defp get_default_variant do
    case Application.get_env(:explorer, :chain_type) do
      :rsk -> "rsk"
      :filecoin -> "filecoin"
      _ -> "geth"
    end
  end
```

<Info>
  BlockScout currently requires a full archive node in order to import every state change for every address on the target network.
</Info>

## Configs

| Application | Environment | Config path                                                                                                                                                      |
| ----------- | ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Explorer    | Dev         | [https://github.com/blockscout/blockscout/tree/master/apps/explorer/config/dev](https://github.com/blockscout/blockscout/tree/master/apps/explorer/config/dev)   |
|             | Prod        | [https://github.com/blockscout/blockscout/tree/master/apps/explorer/config/prod](https://github.com/blockscout/blockscout/tree/master/apps/explorer/config/prod) |
| Indexer     | Dev         | [https://github.com/blockscout/blockscout/tree/master/apps/indexer/config/dev](https://github.com/blockscout/blockscout/tree/master/apps/indexer/config/dev)     |
|             | Prod        | [https://github.com/blockscout/blockscout/tree/master/apps/indexer/config/prod](https://github.com/blockscout/blockscout/tree/master/apps/indexer/config/prod)   |

## Variables to connect to JSON RPC client

| Name                                     | Environment Variable                     | Default Value          | Description                                                                                                                                      |
| ---------------------------------------- | ---------------------------------------- | ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ |
| **HTTP Endpoint**                        | `ETHEREUM_JSONRPC_HTTP_URL`              | http\://localhost:8545 | The HTTP Endpoint is used to fetch `blocks`, `transactions`, `receipts`, `coin/token balances`.                                                  |
| **Fallback HTTP Endpoint**               | `ETHEREUM_JSONRPC_FALLBACK_HTTP_URL`     | (empty)                | Fallback JSON RPC HTTP url.                                                                                                                      |
| **Tracing Endpoint**                     | `ETHEREUM_JSONRPC_TRACE_URL`             | http\://localhost:8545 | The Tracing endpoint is used to fetch `internal transactions` and `block traces`. In most cases this endpoint is identical to the HTTP Endpoint. |
| **Fallback Tracing Endpoint**            | `ETHEREUM_JSONRPC_FALLBACK_TRACE_URL`    | (empty)                | Fallback JSON RPC tracing url.                                                                                                                   |
| **Eth\_call Requests Endpoint**          | `ETHEREUM_JSONRPC_ETH_CALL_URL`          | (empty)                | JSON RPC url for `eth_call` method requests.                                                                                                     |
| **Fallback Eth\_call Requests Endpoint** | `ETHEREUM_JSONRPC_FALLBACK_ETH_CALL_URL` | (empty)                | Fallback JSON RPC `eth_call` url.                                                                                                                |
| **WebSockets Endpoint**                  | `ETHEREUM_JSONRPC_WS_URL`                | ws\://localhost:8546   | The WebSockets endpoint subscribes to `newHeads` which alerts the indexer to fetch the new block from the subscription.                          |

## Geth

More information on Geth JSON-RPC [is available here](https://geth.ethereum.org/docs/interacting-with-geth/rpc).

```bash theme={null}
sudo /usr/bin/geth --http --http.addr 0.0.0.0 --port 30303 --http.port 8545 --http.api debug,net,eth,shh,web3,txpool --ws.api "eth,net,web3,network,debug,txpool" --ws --ws.addr 0.0.0.0 --ws.port 8546 --ws.origins "*" --sepolia --datadir=/rinkeby --syncmode "full" --gcmode "archive" --http.vhosts "*"
```

*Tracing and pruning: By default, state for the last 128 blocks kept in memory. Most states are garbage collected. If you are running a block explorer or other service relying on transaction tracing without an archive node (--gcmode=archive), you need to trace within this window! Alternatively, specify the "reexec" tracer option to allow regenerating historical state; and ideally switch to chain tracing which amortizes overhead across all traced blocks.*

## Erigon

More information on Erigon configuration [is available here](https://erigon.gitbook.io/erigon/advanced-usage/configure-erigon).

## Nethermind

More information on Nethermind configuration [is available here](https://docs.nethermind.io/fundamentals/configuration/).

## Reth

More information on Reth configuration [is available here](https://reth.rs/run/config.html).

## RSKj

More information on RSKj configuration [is available here](https://dev.rootstock.io/rsk/node/configure/reference/).

## Besu

More information on Besu configuration [is available here](https://besu.hyperledger.org/stable/public-networks/how-to/configuration-file).

## Lotus

More information on Lotus configuration [is available here](https://lotus.filecoin.io/lotus/configure/defaults/).

## OpenEthereum

```python theme={null}
--jsonrpc-interface all --jsonrpc-apis web3,eth,net,parity,pubsub,traces --ws-interface all --fat-db=on --pruning=archive --ws-apis all --ws-origins all --ws-hosts all
```


# Database Storage Requirements
Source: https://docs.blockscout.com/setup/requirements/database-storage-requirements



The configuration variable `db_storage` can be used to define the amount of storage allocated to your RDS instance. The chart below shows an estimated amount of storage that is required to index individual chains. Note these numbers are estimates and are constantly increasing.

The `db_storage` can only be adjusted 1 time in a 24 hour period on AWS.

| Chain            | Storage (GiB) |
| ---------------- | ------------- |
| Ethereum Mainnet | 21000         |
| Ethereum Sepolia | 5200          |
| Gnosis Chain     | 21000         |
| Gnosis Chiado    | 470           |
| Ethereum Classic | 555           |

*Note*: as of 23.12.2024


# L2  > L1 JSON RPC Method Requests
Source: https://docs.blockscout.com/setup/requirements/l2-greater-than-l1-json-rpc-method-requests



<Info>
  This page documents the requirements for various rollup types when requesting data from the L1 node.
</Info>

Layer 2 (L2) chains interact with their Layer 1 (L1) counterparts in different ways depending on the rollup type and information required. Blockscout's chain-specific fetchers interact with the L1 node to gather information crucial for tracking the rollup's state, batches, confirmations, and cross-chain messages.

* [Arbitrum](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#arbitrum-rollups)
* [Optimism](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#optimism-rollups)
* [Scroll](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#scroll-l1-fetchers)
* [Shibarium](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#shibarium-l1-fetchers)
* [zkSync](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#zksync-rollups)
* [Polygon zkEVM](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests#polygon-zkevm-l1-fetchers)

The following standard L1 JSON-RPC methods are utilized. Frequency and triggers for these calls are described for each chain below.

| L1 JSON-RPC Method         | Purpose                                                                                               |
| -------------------------- | ----------------------------------------------------------------------------------------------------- |
| `eth_getLogs`              | Discover L1 events (Batches, Confirmations, Executions, Messages, Keysets)                            |
| `eth_getBlockByNumber`     | Get L1 Block Timestamps, Chain Head/Safe Block info                                                   |
| `eth_getTransactionByHash` | Get L1 Tx Calldata (Batches), Get L1 Tx Originator (L1->L2 Messages)                                  |
| `eth_call`                 | Get Keyset Creation Block from `SequencerInbox` contract (Used infrequently for Arbitrum chains only) |

***

## Arbitrum Rollups

### L1 JSON-RPC method details

#### Method: `eth_getLogs`

Used periodically to poll for specific L1 events emitted by Arbitrum contracts. The polling intervals are generally configurable (`INDEXER_ARBITRUM_BATCHES_TRACKING_RECHECK_INTERVAL` and `INDEXER_ARBITRUM_TRACKING_MESSAGES_ON_L1_RECHECK_INTERVAL` for new events, faster polling for historical catch-up).

* **Events Polled:**
  * `SequencerBatchDelivered` (from `SequencerInbox` contract): To discover new L1 batches containing L2 block data. Polled periodically by the batch tracking worker (`TrackingBatchesStatuses`).
  * `SendRootUpdated` (from `Outbox` contract): To discover L2 block confirmations. Polled periodically by the batch tracking worker.
  * `OutBoxTransactionExecuted` (from `Outbox` contract): To discover L2-to-L1 message executions on L1. Polled periodically by the batch tracking worker.
  * `MessageDelivered` (from `Bridge` contract): To discover L1-to-L2 message initiations on L1. Polled periodically by the L1 message tracking worker (`TrackingMessagesOnL1`).
  * `SetValidKeyset` (from `SequencerInbox` contract): To retrieve details about AnyTrust Data Availability Committee keysets. This is triggered **on-demand** when processing an AnyTrust batch that references a keyset hash not yet seen in the database.

***

#### Method: `eth_getBlockByNumber`

* **Fetching Timestamps:**
  * Called frequently **in response to processing events** found via `eth_getLogs`. When a relevant event (like batch delivery, confirmation, or message execution) is found in a log, this method is called for the corresponding L1 block number to get its timestamp. This happens in batches triggered by the periodic log polling.
* **Fetching Chain Head/Safe Block:**
  * Called periodically (driven by `recheck_interval`) with tags `"latest"` and `"safe"` to determine the current L1 chain head and the safe block for reorg protection and determining finality. Used by batch, confirmation, and execution workers.
  * Called once during initialization to determine the starting point if not explicitly configured.

***

Method: `eth_getTransactionByHash`

Called **in response to processing events** found via `eth_getLogs`:

* **Fetching Batch Calldata:**
  * When a `SequencerBatchDelivered` event is processed, this method is called for the L1 transaction hash associated with the event to retrieve the transaction's `input` data (calldata). This calldata contains essential batch information, especially for non-blob batches.
* **Fetching L1->L2 Message Originator:**
  * When a `MessageDelivered` event (for an L1->L2 message) is processed, this method is called for the L1 transaction hash to retrieve the originator (`from`) address.

***

Method: `eth_call`

Used less frequently than the other calls.

* **Fetching Keyset Creation Block:**
  * When processing an AnyTrust batch referencing a previously unknown keyset hash, an `eth_call` is made to the `SequencerInbox` contract's `getKeysetCreationBlock` function to determine the L1 block where the keyset became active. This is triggered **on-demand** during batch processing.

***

## Optimism Rollups

### Optimism L1 fetchers

Method calls are described for each of the Optimism-based fetchers including Deposit, DisputeGame, OutputRoot, TransactionBatch and WithdrawalEvent.

#### Indexer.Fetcher.Optimism.Deposit

* `eth_getLogs` (driven by `INDEXER_OPTIMISM_L1_ETH_GET_LOGS_RANGE_SIZE` for catchup mode) - one request per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` response to get block timestamp. Batch request is used, so one batch request per one `eth_getLogs` call

#### Indexer.Fetcher.Optimism.DisputeGame

* call to `OptimismPortal`'s `respectedGameType()` public getter (every 60 seconds)
* call to `DisputeGameFactory`'s `gameCount` public getter (every 60 seconds)
* call to `DisputeGameFactory`'s `gameAtIndex` public getter (max 50 items per batch request) and the corresponding batch calls to `extraData`, `resolvedAt`, `status` public getters for each dispute game
* call to `DisputeGameFactory`'s `resolvedAt` public getter (max 50 items per batch request) for max 1000 last unresolved games
* call to `DisputeGameFactory`'s `status` public getter (max 50 items per batch request) for max 1000 last resolved games

#### Indexer.Fetcher.Optimism.OutputRoot

* `eth_getLogs` (driven by `INDEXER_OPTIMISM_L1_ETH_GET_LOGS_RANGE_SIZE` for catchup mode) - one request per block in realtime mode

#### Indexer.Fetcher.Optimism.TransactionBatch

* `eth_getBlockByNumber` (batch RPC calls containing up to `INDEXER_OPTIMISM_L1_BATCH_BLOCKS_CHUNK_SIZE` requests per batch in catchup mode starting from the start block defined in `SystemConfig` contract) - one request per block in realtime mode

#### Indexer.Fetcher.Optimism.WithdrawalEvent

* `eth_getLogs` (driven by `INDEXER_OPTIMISM_L1_ETH_GET_LOGS_RANGE_SIZE` for catchup mode) - one request per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` response to get block timestamp. Batch request is used, so one batch request per one `eth_getLogs` call

***

## zkSync Rollups

### **L1 interaction process**

Blockscout's zkSync-specific fetchers verify zkSync batch status and transitions (Committed, Proven, Executed) recorded on the L1.

### **L1 interaction summary**

L1 calls are infrequent and only triggered to confirm L1 state transitions suggested by the L2 node.

* L1 interaction is driven by the `BatchesStatusTracker`. This tracker performs periodic checks based on the `INDEXER_ZKSYNC_BATCHES_STATUS_RECHECK_INTERVAL` ENV variable setting.
* Each check phase (`:check_committed`, `:check_proven`, `:check_executed`) *first* queries the L2 node via RPC (`zks_getL1BatchDetails`).
* If (*and only if)* the L2 query indicates a new L1 transaction hash associated with a batch's status change (commit, prove, or execute), the corresponding L1 RPC method (`eth_getTransactionReceipt` or `eth_getTransactionByHash`) is called for that *specific* transaction hash.

### L1 JSON-RPC method details

#### Method: `eth_getTransactionReceipt`

**Purpose**: Retrieves the receipt of an L1 transaction suspected of changing a batch's status (commit or execute). The fetcher specifically looks for event logs within the receipt (`BlockCommit` or `BlockExecution` events) to confirm which batches were affected by that single L1 transaction.

**Frequency:**

* Called conditionally by the `BatchesStatusTracker` process.
* This tracker runs in a loop with a configurable `INDEXER_ZKSYNC_BATCHES_STATUS_RECHECK_INTERVAL`.
* Within this loop, it first checks the L2 RPC (`zks_getL1BatchDetails`) for the oldest uncommitted/unexecuted batch.
* If the L2 RPC response indicates a new commit or execute L1 transaction hash associated with that batch, *then* `eth_getTransactionReceipt` is called on the L1 node for that specific transaction hash.
* It does *not* poll L1 constantly; the call is triggered only when a potential status change is detected via L2 RPC data during the periodic check.

***

#### Method: `eth_getTransactionByHash`

**Purpose:** Retrieves the details of an L1 transaction suspected of proving one or more zkSync batches. The fetcher needs the transaction's `input` (calldata) to decode the list of batches proven in that single L1 transaction.

**Frequency**:

* Called conditionally by the `BatchesStatusTracker` process, similar to `eth_getTransactionReceipt`. It also runs within the tracker's periodic `INDEXER_ZKSYNC_BATCHES_STATUS_RECHECK_INTERVAL`.
* The tracker checks the L2 RPC (`zks_getL1BatchDetails`) for the oldest unproven batch. If the L2 RPC response indicates a new prove L1 transaction hash, *then* `eth_getTransactionByHash` is called on the L1 node for that specific transaction hash to retrieve its calldata.
* Like the receipt fetch, this is triggered by potential changes detected via L2 RPC during the periodic check, not through constant L1 polling.

***

## Polygon zkEVM L1 fetchers

Method calls are described for each of the zkEVM-based fetchers including BridgeL1, BridgeL1Tokens, and TransactionBatch.

#### Indexer.Fetcher.PolygonZkevm.BridgeL1

* `eth_getLogs` (max 1000 blocks in a range per request for catchup mode) - one request per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` response to get block timestamp (batch request is used with max 50 items per request)
* `eth_getBlockByNumber` to get latest block (every block time in seconds, divided by 2)
* one batch request (with calls to `symbol()` and `decimals()` getters of token contracts) per one `eth_getLogs` call

#### Indexer.Fetcher.PolygonZkevm.BridgeL1Tokens

* one batch request (with calls to `symbol()` and `decimals()` getters of token contracts) per one set of logs taken in realtime mode from the L2 block

#### Indexer.Fetcher.PolygonZkevm.TransactionBatch

* a batch call of `zkevm_batchNumber`, `zkevm_virtualBatchNumber`, `zkevm_verifiedBatchNumber` requests per `INDEXER_POLYGON_ZKEVM_BATCHES_RECHECK_INTERVAL` seconds
* a batch call of `zkevm_getBatchByNumber` requests per `INDEXER_POLYGON_ZKEVM_BATCHES_CHUNK_SIZE` zkEVM batches

***

## Scroll L1 fetchers

Method calls are described for each of the Scroll-based fetchers including Batch and BridgeL1.

#### Indexer.Fetcher.Scroll.Batch

* `eth_getLogs` (driven by `INDEXER_SCROLL_L1_ETH_GET_LOGS_RANGE_SIZE` for catchup mode) - one request per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` response to get block timestamp (batch request is used with max 50 items per request)
* `eth_getBlockByNumber` to get latest block (every block time in seconds, divided by 2)

#### Indexer.Fetcher.Scroll.BridgeL1

* `eth_getLogs` (driven by `INDEXER_SCROLL_L1_ETH_GET_LOGS_RANGE_SIZE` for catchup mode) - one request per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` response (taking into account `SentMessage` events only) to get block timestamp (batch request is used with max 50 items per request)
* `eth_getBlockByNumber` to get latest block (every block time in seconds, divided by 2)

## Shibarium L1 fetchers

Method calls are described for each of the Scroll-based fetchers including L1 and RollupL1ReorgMonitor.

#### Indexer.Fetcher.Shibarium.L1

* three `eth_getLogs` requests per chunk for catchup mode (max 1000 blocks in a chunk) - three requests per block in realtime mode
* `eth_getBlockByNumber` for each block within `eth_getLogs` responses (taking into account deposit events only) to get block timestamp (batch request is used with max 50 items per request)
* `eth_getBlockByNumber` to get latest block (every block time in seconds, divided by 2)

#### Indexer.Fetcher.RollupL1ReorgMonitor

* `eth_getBlockByNumber` to get latest block (every block time in seconds, divided by 2)


# Node Tracing / JSON RPC Requirements
Source: https://docs.blockscout.com/setup/requirements/node-tracing-json-rpc-requirements



### Standard JSON RPC Requirements

* Archive node with JSON RPC interface should strictly follow input/output interface described in [https://ethereum.github.io/execution-apis/api-documentation/](https://ethereum.github.io/execution-apis/api-documentation/)
* WebSocket interface (optional/highly recommended to enable) is used to subscribe to new block heads. Otherwise, Blockscout will trigger new blocks fetching by periodical polling the JSON RPC `eth_blockNumber` method.
* Support for the following standard Ethereum JSON RPC methods (documented at [https://ethereum.github.io/execution-apis/api-documentation/](https://ethereum.github.io/execution-apis/api-documentation/))
  * `eth_blockNumber`
  * `eth_call`
  * `eth_getBalance`
  * `eth_getCode`
  * `eth_getBlockByHash`
  * `eth_getBlockByNumber`
  * `eth_getTransactionByHash`
  * `eth_getTransactionByBlockHashAndIndex`
  * `eth_getTransactionByBlockNumberAndIndex`
  * `eth_getTransactionReceipt`
  * `eth_getUncleByBlockHashAndIndex`
  * `eth_getLogs`

### **Fetching Pending Transactions**

*Note pending transactions must be supported by the RPC node to enable this functionality with Blockscout*

| Client                  | Method                       |
| ----------------------- | ---------------------------- |
| Nethermind OpenEthereum | `parity_pendingTransactions` |
| Geth Erigon             | `txpool_content`             |

### Enable Tracing to Fetch Internal Transactions

| Client                         | Method                                                                                                                                                                                                                                                                                                                                                                          |
| ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Erigon Nethermind OpenEthereum | • `trace_replayBlockTransactions` (fetching of internal transactions)<br /><br />• `trace_block` (fetching of block rewards)                                                                                                                                                                                                                                                    |
| Geth                           | • `debug_traceBlockByNumber`<br /><br />• or `debug_traceTransaction`<br /><br />`callTracer` is used by default, starting from the Blockscout 5.1.0 release. To switch to a custom JS tracer, the Blockscout maintainer should set the `export INDEXER_INTERNAL_TRANSACTIONS_TRACER_TYPE=js` environment variable. Prior to the 5.1.0 release, js tracer was a default option. |
| RSK                            | • `trace_block` (fetching of internal transactions)                                                                                                                                                                                                                                                                                                                             |

### JSON RPC Performance Benchmarks

Time measures for response time of crucial JSON RPC methods for indexing in Blockscout. [Ways to improve speed](/faqs/faqs#how-do-i-speed-up-my-self-hosted-instance).

1. `eth_getBlockByNumber` without transaction receipts for a block with 15 transactions: Desired response time is \< 0.5s. For instance, in case of the Gnosis chain archive node, the response time for the block with \~20 transactions is \~0.4s.
2. `eth_getTransactionReceipt` for random transactions desired response time is \< 0.5s. For the Gnosis chain archive node the response time is \~0.3 - 0.4s.
3. Batched `eth_getTransactionReceipt` for 15 transactions acceptable response time is Less than 1s. For the Gnosis chain archive node, it is \~0.6 - 0.7s

### Rate Limit

The desired rate limit for RPC endpoint is 200 req/sec for the indexing phase and 100 req/sec for the indexed chain.

### EVM Requirements & Clients

* All EVM chains must [define these variables](/setup/env-variables#required-env-variables) during configuration.
* BlockScout currently supports Erigon, Geth, Nethermind, Hyperledger Besu, and Anvil clients. Define the node variant using the `ETHEREUM_JSONRPC_VARIANT` environment variable. [More information](/setup/requirements/client-settings)

### L2 -> L1 JSON RPC Methods

* Find information on JSON RPC method use with [different L2 types.](/setup/requirements/l2-greater-than-l1-json-rpc-method-requests)


# General Backend Requirements / Blockscout Backend Prerequisites
Source: https://docs.blockscout.com/setup/requirements/requirements



<Tip>
  Install the software below prior to Blockscout installation. For additional requirements see:

  * [Database Storage Requirements](/setup/requirements/database-storage-requirements): Storage required for common chains to give a sense of needed storage

  * [Node Tracing Requirements](/setup/requirements/node-tracing-json-rpc-requirements): JSON RPC methods

  * [Client Setting Requirements](/setup/requirements/client-settings): Settings related to client implementations (ie Geth, OpenEthereum, etc)

  * [Hardware/Hosting Requirements](/setup/requirements/resource-requirements): Base requirements for a hosted instance of Blockscout.
</Tip>

| Dependency                                                       | Mac                       | Linux                                                                                                                                                           |
| ---------------------------------------------------------------- | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Erlang/OTP 26](https://github.com/erlang/otp)                   | `brew install erlang`     | [Erlang Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L134)   |
| [Elixir 1.15.x](https://elixir-lang.org/)                        | `brew install elixir`     | [Elixir Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L138)   |
| [Postgres 12, 13, 14](https://www.postgresql.org/)               | `brew install postgresql` | [Postgres Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L187) |
| [Node.js 18.x.x](https://nodejs.org/en/)                         | `brew install node`       | [Node.js Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L66)   |
| [Automake](https://www.gnu.org/software/automake/)               | `brew install automake`   | [Automake Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L72)  |
| [Libtool](https://www.gnu.org/software/libtool/)                 | `brew install libtool`    | [Libtool Install Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L62)   |
| [Inotify-tools](https://github.com/rvoicilas/inotify-tools/wiki) | Not Required              | Ubuntu - `apt-get install inotify-tools`                                                                                                                        |
| [GCC Compiler](https://gcc.gnu.org/)                             | `brew install gcc`        | [GCC Compiler Example](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L70)      |
| [GMP](https://gmplib.org/)                                       | `brew install gmp`        | [Install GMP Devel](https://github.com/poanetwork/blockscout-terraform/blob/33f68e816e36dc2fb055911fa0372531f0e956e7/modules/stack/libexec/init.sh#L74)         |
| Make                                                             | -                         | `sudo apt install make`if Debian 9                                                                                                                              |
| G++ Compiler                                                     | -                         | `sudo apt install g++`if Debian 9                                                                                                                               |

Additional requirements for Blockscout versions below 5.1.3:

| Dependency | Mac | Linux                                                   |
| ---------- | --- | ------------------------------------------------------- |
| Rust       | -   | [Install Rust](https://www.rust-lang.org/tools/install) |
| Cargo      | -   | Ubuntu - `apt-get install cargo`                        |


# Hardware & Hosting Requirements
Source: https://docs.blockscout.com/setup/requirements/resource-requirements



Resource requirements may vary based on chain size and other parameters. This mainly impacts [database storage](/setup/requirements/database-storage-requirements) requirements. Basic [prerequisites](/setup/requirements/requirements) and settings can be found throughout the [Information and Settings](/setup/information-and-settings) section for developers.

BlockScout requires a full archive node to import every state change for every address on the target network.

## Recommended Base Hardware

EVM chains can differ in size and requirements, these are the recommendations for optimal performance.

| CPU | 16 core, 32 thread |
| --- | ------------------ |
| RAM | 128GB              |

## Hosting Requirements

Minimums are listed for an AWS Cloud instance and can be inferred to other hosting providers.

|                               |                                                                                                                                                                                                                                                                      |
| ----------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Application                   | • 1x EC2 m5a.xlarge instance running Linux<br /><br />• 8GB of EBS General Purpose SSD (NVMe)                                                                                                                                                                        |
| Database                      | • 1x RDS Database running on db.t3.large using PostgreSQL v12+<br /><br />• 500GB of General Purpose SSD (depending on chain size)<br /><br />• See [Database Storage Requirements](/setup/requirements/database-storage-requirements) for chain-relevant baselines. |
| Amazon Elastic Load Balancing | • Average 100 new connections/sec per Elastic Load Balancer                                                                                                                                                                                                          |

<Info>
  Requirements will vary based on chain. For example, these are the recommended requirements for a Harmony Explorer Node:

  **Setup**: AWS i3en.12xlarge or equivalent, with local disk storage **Storage**: \~24TB (4x NVMe SSD) is recommended for Archival Explorer Nodes on Shard 0 **OS**: Latest Ubuntu Linux (LTS Version) **Network**: 100M+ bandwidth
</Info>

<Tip>
  For additional information, see:

  * [General Requirements:](/setup/requirements/requirements) Software required for deployment

  * [Database Storage Requirements](/setup/requirements/database-storage-requirements): Storage required for common chains to give a sense of needed storage

  * [Node Tracing Requirements](/setup/requirements/node-tracing-json-rpc-requirements): JSON RPC methods

  * [Client Setting Requirements](/setup/requirements/client-settings): Settings related to client implementations (ie Geth, OpenEthereum, etc)
</Tip>


# Testing
Source: https://docs.blockscout.com/setup/testing

How to test Blockscout, including requirements, commands, and environment setup.

### Requirements

* Install `chromedriver` . It is required to run tests from `./apps/block_scout_web` of the Umbrella application.
* This set of environment variables is required for each run of the test (`mix test`) suite:

  ```bash theme={null}
  export MIX_ENV=test
  export POSTGRES_DB=explorer_test
  export POSTGRES_PASSWORD=postgres
  export POSTGRES_USER=postgres
  export CHAIN_ID=77
  ```

  Since v6.6.0, there are more flexible options for configuring the database used in testing. Refer to the `TEST_DATABASE_URL` and `DATABASE_READ_ONLY_API_URL` environment variables for more details.

  ```bash theme={null}
  export MIX_ENV=test
  export TEST_DATABASE_URL=postgresql://postgres:postgres@postgres-host:5432/explorer_test
  export CHAIN_ID=77
  ```

### Running tests

1. Build assets. `cd apps/block_scout_web/assets && npm run build; cd -`
2. Format Elixir code. `mix format`
3. Lint Elixir code. `mix credo --strict`
4. Run the dialyzer. `mix dialyzer --halt-exit-status`
5. Check the Elixir code for vulnerabilities. `cd apps/explorer && mix sobelow --config; cd -` `cd apps/block_scout_web && mix sobelow --config; cd -`
6. Lint JavaScript code. `cd apps/block_scout_web/assets && npm run eslint; cd -`
7. Test JavaScript code. `cd apps/block_scout_web/assets && npm run test; cd -`
8. Run separate test suites for the Umbrella application<br />- `indexer`<br />`mix do ecto.create --quiet, ecto.migrate && cd apps/indexer && mix do compile, test --no-start && cd -`<br /><br />- `explorer`<br />`mix do ecto.create --quiet, ecto.migrate && cd apps/explorer && mix do compile, test --no-start && cd -`<br /><br />- `block_scout_web`<br />`mix do ecto.create --quiet, ecto.migrate && cd apps/block_scout_web && mix do compile, test --no-start && cd -`<br /><br />- `ethereum_jsonrpc`<br />`mix do ecto.create --quiet, ecto.migrate && cd apps/ethereum_jsonrpc && mix do compile, test --no-start && cd -`

### **Nethermind**

**Mox**

**This is the default setup. **`mix test --no-start`** will work on its own, but to be explicit, use the following setup**:

```bash theme={null}
ETHEREUM_JSONRPC_CASE=EthereumJSONRPC.Case.Nethermind.Mox \
ETHEREUM_JSONRPC_WEB_SOCKET_CASE=EthereumJSONRPC.WebSocket.Case.Mox \
mix test --no-start --exclude no_nethermind
```

**HTTP / WebSocket**

```bash theme={null}
ETHEREUM_JSONRPC_CASE=EthereumJSONRPC.Case.Nethermind.HTTPWebSocket \
ETHEREUM_JSONRPC_WEB_SOCKET_CASE=EthereumJSONRPC.WebSocket.Case.Nethermind \
mix test --no-start --exclude no_nethermind
```

| Protocol  | URL                     |
| --------- | ----------------------- |
| HTTP      | `http://localhost:8545` |
| WebSocket | `ws://localhost:8546`   |

### **Geth**

**Mox**

```bash theme={null}
ETHEREUM_JSONRPC_CASE=EthereumJSONRPC.Case.Geth.Mox \
ETHEREUM_JSONRPC_WEB_SOCKET_CASE=EthereumJSONRPC.WebSocket.Case.Mox \
mix test --no-start --exclude no_geth
```

**HTTP / WebSocket**

```bash theme={null}
ETHEREUM_JSONRPC_CASE=EthereumJSONRPC.Case.Geth.HTTPWebSocket \
ETHEREUM_JSONRPC_WEB_SOCKET_CASE=EthereumJSONRPC.WebSocket.Case.Geth \
mix test --no-start --exclude no_geth
```

| Protocol  | URL                                               |
| --------- | ------------------------------------------------- |
| HTTP      | `https://mainnet.infura.io/8lTvJTKmHPCHazkneJsY`  |
| WebSocket | `wss://mainnet.infura.io/ws/8lTvJTKmHPCHazkneJsY` |


# Autoscout Explorer Launchpad
Source: https://docs.blockscout.com/using-blockscout/autoscout

Deploy a production-ready instance on the cloud in 5 minutes

Autoscout is a self-service launchpad for chains and rollups looking to deploy an explorer quickly on hosted infrastructure. It is optimized for many chain types including Optimistic and Arbitrum Orbit rollups and zk rollups including Polygon zkEVM and zkSync.

<Check>
  Autoscout is now available at [https://deploy.blockscout.com/](https://deploy.blockscout.com/)
</Check>

### Get Started with Autoscout

1. **Create an account:** To get started, go to [https://deploy.blockscout.com/](https://deploy.blockscout.com/), create an account, and login to get started.
2. **Purchase credits:** You will need credits to launch your explorer. Each credit costs \$1.00. Purchase via Stripe with a credit card; a crypto option is coming soon. Credits are deducted in real time, see the pricing table below for costs.

   **You can start with any amount of credits to test your instance. Instances cost between 0.35 - 1.35 credits per hour, depending on the size.**

   a. If you are testing the service, request test credits in the [Blockscout Discord](https://discord.gg/blockscout) `#autoscout` channel. Share your email and request and we will top off your account for testing.
3. **Add a new instance:** Click the Add instance button to get started.
4. **Add your network info**: See below for info on configuration and parameters.
5. **Deploy your explorer:** Click save and deploy to start the deployment process. In 5-10 minutes your explorer will be live and indexing your chain. Once deployed you can access your explorer link.

## Autoscout Pricing

Autoscout is a pay-as-you-go service. **Start with any amount of credits** and **increase the balance at any time**.

If your account runs out of credits your instance will be stopped until you top your account back up. If this happens, you will need to relaunch (and reindex) your instance once you add additional credits. Instances will scale based on daily transactions, so be sure to monitor and top up accordingly.

<Frame>
  <img alt="" />
</Frame>

| Size                     | Hourly | Daily | Weekly | Monthly |
| ------------------------ | ------ | ----- | ------ | ------- |
| xSmall brand new chain   | .35    | 8.50  | 60     | 252     |
| Small \<50K tx per day   | .485   | 12    | 84     | 349     |
| Medium \<150K tx per day | .972   | 24    | 168    | 700     |
| Large \<1M tx per day    | 1.32   | 32    | 224    | 950     |

## Create Instance

There are several tabs to fill out to launch your instance; Info, Branding, and Rollup config (if needed). Plugins (currently the only live plugin is stats) can be added once your instance is fully indexed.

You can edit parameters at any time, but this typically requires relaunching and reindexing the instance.

### Info

<Frame>
  <img alt="" />
</Frame>

The following parameters are in the Info section. \* parameters are required.

* **Instance size\***: Select based on the number of transactions anticipated for the instance. The costs are currently placeholders, but your credits will be impacted according to chain usage.
* **Chain name**: The chain name will be shown in the top explorer banner.
* **Instance name\***: A label for your instance, it is reflected in the url of the instance ie [https://instance-name.cloud.blockscout.com/](https://instance-name.cloud.blockscout.com/)
* **Chain ID**: If you don't know the chain ID you can get with the `eth_chainId` JSON-RPC method.
* **Node type:** Choose from the list of clients for the archive node:
  * Besu, Erigon, Anvil, Geth, Parity
* **Gas token symbol**: Will show in the interface, for example ETH if your chain uses Ether for gas.
* **Mainnet or Testnet**: Select the type of chain, if Testnet a label will be added to the instance.
* **This chain is a Rollup**: If selected, another field will appear to select **Arbitrum, Optimism, Polygon zkEVM or zkSync**. You will then fill out additional information in the Rollup Config tab.
* **HTTP RPC URL\***: The **archive node** url ([https://your-rpc-url](https://your-rpc-url)) [***Note: archive node is required for internal transactions and token/coin historical balances. Tracing should be enabled for internal transactions.***](/setup/requirements/node-tracing-json-rpc-requirements)
* **WS URL**: The websocket url (wss\://ws.your-websocket-url)
* **Chain spec URL**: URL to chain specification path json (Sepolia example: [chainspec.json](https://github.com/ethpandaops/ethereum-genesis-generator/blob/v4.1.8/apps/el-gen/sepolia/chainspec.json) or [genesis.json](https://github.com/ethpandaops/ethereum-genesis-generator/blob/v4.1.8/apps/el-gen/sepolia/genesis.json)). You will use the raw JSON file; in the Sepolia example this url is [https://raw.githubusercontent.com/ethpandaops/ethereum-genesis-generator/v4.1.8/apps/el-gen/sepolia/chainspec.json](https://raw.githubusercontent.com/ethpandaops/ethereum-genesis-generator/v4.1.8/apps/el-gen/sepolia/chainspec.json)
* **Custom Domain**: You can use a custom domain for your instance but must configure your DNS and add a DNS `CNAME` record pointing to `autoscout.cname.blockscout.com`
* **Domain redirect(s):** Any additional domain names to redirect to the instance, comma separated.
* **Public RPC URL**: Enables 'add to MetaMask button'. Can be the same as the RPC URL if this is a public node.
* **WalletConnect project ID:** Enables the ability for Read and Write functionality with smart contracts. [Learn more about setting one up here](/setup/configuration-options/walletconnect-project-id-for-contract-read-write).
* **Google Analytics property ID**: Add the ID for your GA account if desired.

### Branding

<Frame>
  <img alt="" />
</Frame>

* **Announcement banner:** Add an optional banner to the top of your instance, can include HTML code.
* **Default color theme**: Choose between a light theme and 3 variations of a darker theme.
* **Default address identicon:** Select from 4 different options for default identicons in your instance.
* **Vertical or Horizontal menu**: Select vertical for a side menu or horizontal for a top menu.
* **Full logo URL**: Add a url link to your full logo image in horizontal format. Supported formats: image/jpeg, image/gif, image/png. Add one for light mode and one for dark mode if desired (users can switch modes manually).
* **Logo sign (square) URL**: Add a url link to your square logo image in horizontal format. Supported formats: image/jpeg, image/gif, image/png. Add one for light mode and one for dark mode if desired (users can switch modes manually).
* **Header background gradient and text color**: Choose your desired background color gradients with the selector and choose your preferred text color. You will see a preview in the interface.
* **Favicon and OG image URL**: Add your favicon and [OG image](https://ogp.me/). OG image specs: Minimum image size is 200×20pixels (recommended: 1200×600); maximum supported file size is 8 MB; 2:1 aspect ratio; supported formats: image/jpeg, image/gif, image/png
* **OG description**: Add a description for Open Graph Previews
* **Enable enhanced OG tags**: Toggle if you want to render OG tags for API data pages
* **Enable enhanced SEO**: Toggle if you want to rerender page titles for Stats and Tokens pages to enhance SEO
* **API documentation links**: Toggle to show/hide different API links in the navigation menu
* **Other Navigation links**: Add custom navigation links to the other section of the primary navigation menu
* **Footer links**: Add up to 3 columns along with titles and urls for the links you want added to each column.
* **Ads**: Select providers for Ads on your instance

### Indexer

Indexer information uses the following variables under the hood. If no information is fiileed in , default variables are used.

| Variable                                    | Default |
| ------------------------------------------- | ------- |
| `INDEXER_RECEIPTS_BATCH_SIZE`               | 250     |
| `INDEXER_RECEIPTS_CONCURRENCY`              | 10      |
| `INDEXER_INTERNAL_TRANSACTIONS_BATCH_SIZE`  | 10      |
| `INDEXER_INTERNAL_TRANSACTIONS_CONCURRENCY` | 4       |
| `INDEXER_CATCHUP_BLOCKS_BATCH_SIZE`         | 10      |
| `INDEXER_CATCHUP_BLOCKS_CONCURRENCY`        | 10      |
| `INDEXER_COIN_BALANCES_BATCH_SIZE`          | 100     |
| `INDEXER_COIN_BALANCES_CONCURRENCY`         | 4       |
| `INDEXER_TOKEN_BALANCES_BATCH_SIZE`         | 100     |
| `INDEXER_TOKEN_BALANCES_CONCURRENCY`        | 10      |

### Disable pending transactions fetcher

Leave this setting alone if your RPC supports pending transactions. However, **If your RPC node does not support pending transactions, please toggle this switch to disable.**

<Info>
  \*\*Check pending TX support \*\*by sending a request for one of the common methods (`eth_getBlockByNumber` with `"pending"` or `txpool_content`) and observe the response. A successful, valid response confirms support. 
</Info>

**Block transformer:** Leave as base unless you are using clique.

[Find additional info variables relevant to indexer setup here](https://docs.blockscout.com/setup/env-variables/backend-env-variables#indexer-management)

### Rollup Config

If your chain is a rollup you will select this in the info screen and then fillout the associated Rollup config info.

<Info>
  * Read the [Rollup deployment and config details](https://docs.blockscout.com/setup/deployment/rollup-deployment#arbitrum)
    * [Arbitrum](/setup/env-variables/backend-envs-chain-specific#arbitrum-management) ENV variables
    * [Optimism](/setup/env-variables/backend-envs-chain-specific#optimism-rollup-management) ENV variables
    * [Polygon zkEVM](https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#polygon-zkevm-rollup-management) ENV variables
    * [zkSync](https://docs.blockscout.com/setup/env-variables/backend-envs-chain-specific#zksync-rollup-management) ENV variables
</Info>

<Frame>
  <img alt="" />
</Frame>

## FAQ

<AccordionGroup>
  <Accordion title="Why can't I see internal transactions?">
    There could be several reasons for this. Your RPC may not be an archive node and [tracing](/setup/requirements/node-tracing-json-rpc-requirements) may not be turned on for that node. Once you switch to an RPC with tracing enabled internal transactions will still not be indexed until you spin up a new instance. In this case you will need to shut down your instance and create a new one.
  </Accordion>

  <Accordion title="Is there an Autoscout API?">
    Yes, there is but it requires an API key to use. It can be useful if you are spinning up many instances or need to check on many instances at the same time. Contact us in Discord #autoscout channel to request an API key. See the API Swagger Docs for more info: [https://blockscout.github.io/swaggers/services/autoscout/main/index.html](https://blockscout.github.io/swaggers/services/autoscout/main/index.html)
  </Accordion>

  <Accordion title="How do I add a domain / subdomain on Cloudflare using CNAME?">
    These are the fields you need to fill out in Cloudflare:

    * **Type:** CNAME
    * **Name:** your-explorer-name (instance name)
    * **Content:** autoscout.cname.blockscout.com
    * **Proxy status:** DNS only
    * **TTL:** Auto

      <img alt="Cloudflare Jp" />

    Make sure to set your Custom domain in the Autoscout interface.

    <img alt="My Custom Domain Jp" />
  </Accordion>

  <Accordion title="When do I receive automated emails informing me my credits are running out?">
    You will receive several automated emails when your Autoscout credits/funds are running out. They are sent according to the following schedule:

    | **Days before running out of funds** | **Automated email** |
    | ------------------------------------ | ------------------- |
    | 5 days                               | Initial email       |
    | 3 days                               | Reminder email      |
    | 1 day                                | Final reminder      |
  </Accordion>

  <Accordion title="How do I upgrade to the latest version of Blockscout with Autoscout?">
    Updating is easy! Simply  **restart** your instance and it is automatically updated to the latest version.
  </Accordion>
</AccordionGroup>


# Dappscout Apps Marketplace
Source: https://docs.blockscout.com/using-blockscout/blockscout-apps

Dappscout is a curated collection of on-chain applications

<Check>
  💡 Submit your dapp now [with this quick form](https://airtable.com/appiy5yijZpMMSKjT/shr6uMGPKjj1DK7NL)!
</Check>

Dappscout Apps Marketplace provides a curated list of apps available to on-chain users. Projects can submit their project for review, and once accepted, the project is listed in the marketplace.

<Frame>
  <img />
</Frame>

## Direct Interface

Dapps are either embedded into the interface directly (like this [Uniswap example](https://optimism.blockscout.com/apps/uniswap)) or added as 3rd party links. When embedded, a user can connect their web3 wallet once to Blockscout, then use it with all of the supported Dapps. This saves time and makes for a seamless user experience when switching between multiple applications.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

<Info>
  To enable direct embedding, Dapps need to:

  1. Support iframe embedding on 3rd party domains.

  2. Integrate the [Safe Apps SDK](https://docs.safe.global/apps-sdk-overview).

  *See *[*Dapp integration*](/using-blockscout/blockscout-apps/dapp-integration)* for more details.*
</Info>

## Dapps you can Trust

Dappscout marketplace provides additional security and peace of mind when interacting with various Dapps on a chain. Rather than accessing potentially fake links, scam sites or compromised interfaces, all Dapps in Blockscout are vetted and added by the curation team. Dappscout Dapps are safe and secure for users.

## Dappscout Submissions

There are several ways to submit a DApp. You will fill out a form with basic information to get started.

* Use this form to [submit directly](https://airtable.com/appiy5yijZpMMSKjT/shr6uMGPKjj1DK7NL).

* Use the submit app button within the marketplace.

<Frame>
  <img />
</Frame>

## Blockscout Native Dapps

In addition to 3rd party apps, Blockscout is developing native apps for the Marketplace. These include:

* [Swapscout](/using-blockscout/swapscout): Swapping and bridging application.

* Revokescout: Manage and revoke contract approvals.

## Dapp Star Ratings

Users can rate dapps on a 1-5 star basis. A user must connect their wallet to the explorer, and that wallet must have atleast 5 transactions on the chain in order to rate a dapp. Dapps can be sorted by rating score and the number of ratings.

A full rundown on the process is available in this blog post:

<Card title="Rate dapps with Blockscout" href="https://www.blog.blockscout.com/star-ratings-come-to-dappscout/">
  Blockscout | Multichain Block Explorer For EVM Chains
</Card>

<Info>
  Please note: The star rating system is currently experimental. This feature was released in beta testing to assess user interest in ratings and reviews. Current results may be affected by rating biases, including automated or mass submissions. We're actively improving the system based on user feedback.
</Info>


# DApp Integration
Source: https://docs.blockscout.com/using-blockscout/blockscout-apps/dapp-integration

Prepare your DApp for submission to the DAppscout marketplace

Embedded DApps allow users to connect with a single wallet, providing a seamless user experience that eliminates the need to visit different urls and connect a wallet each time. See the[How to Integrate](/using-blockscout/blockscout-apps/dapp-integration#how-to-integrate)section below to prepare your DApp.

## Integration Levels

There are several levels on integration with DAppscout.

<Check>
  Our goal is to have as many fully integrated apps as possible!
</Check>

1. **Fully Integrated Apps**

   * Apps that are opened in an iFrame on \*.blockscout.com domains and have integrated the Safe Apps SDK

2. **Partially Integrated Apps**

   * Apps that are opened in an iFrame on \*.blockscout.com domains, but have not integrated the Safe Apps SDK for various reasons

3. **Non-Integrated Apps**

   * Apps that are not opened in an iFrame on \*.blockscout.com domains and have not integrated the Safe Apps SDK for various reasons

<Info>
  Fully integrated DApps list higher within the default view
</Info>

## Integration Benefits

<Check>
  Fully integrated apps receive the following benefits
</Check>

1. **Top Places in the Ranking for Users**

   * All fully integrated apps will appear at the top of the list in their categories.

2. **Free Promo Through Ads**

   * Protocols will receive free promotion on Blockscout for a limited time.

3. **Co-Marketing with Blockscout**

   * In addition to free promotion, we’ll prepare a co-marketing campaign on social media and our blog.

4. **A Special Quality Mark**

   * All fully integrated DApps have a green “Fully-Integrated” symbol which shows users it is ready for use.

<Frame>
  <img />
</Frame>

## How to Integrate

To fully integrate your protocol into DAppscout, you will need to do 3 things.

1. Enable iFrames for the \*.blockscout.com domain

2. Integrate the Safe Apps SDK

3. Submit your DApp via the form

### 1) Enable iFrame support

Both fully and partially integrated apps in the marketplace are embedded using iFrames, and it is necessary to enable iFrame support for our domain - \*.blockscout.com. This can typically be done via the `frame-ancestors` directive of the `Content-Security-Policy` header in your application. For additional examples, please see [https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-ancestors](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-ancestors).

Also, check your [CORS](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) settings, these may need to be modified for the \*.blockscout domain

### 2) Integrate the Safe Apps SDK

DAppscout uses the Safe Apps SDK to automatically connect a wallet linked to Blockscout to any of the apps in our marketplace. This allows a visitor to connect a wallet once and then open any app without needing to connect the wallet again

To enable this functionality, Safe Apps SDK needs to be integrated for your protocol, and the \*.blockscout.com domain added as an exception.

The [SAFE SDK documentation page](https://docs.safe.global/apps-sdk-get-started) provides resources to help you through the process. You will need to pass \*.[blockscout.com](http://blockscout.com/) as an additional option to the SafeAppsSDK function into the code [here](https://github.com/safe-global/safe-apps-sdk/tree/main/packages/safe-apps-sdk#documentation).

For additional integration options, check the list of other Safe packages for Safe Apps at [https://github.com/safe-global/safe-apps-sdk?tab=readme-ov-file#packages](https://github.com/safe-global/safe-apps-sdk?tab=readme-ov-file#packages)

If you integrate any of these packages, DAppscout can use them to automatically connect a wallet to your app.

<Warning>
  After integrating the Safe Apps, make sure you have added the \*.blockscout.com domain as an exception to the SDK. Otherwise, we cannot utilize the Safe Apps SDK on our website
</Warning>

<Warning>
  It is not necessary to have the Safe app/smart contracts on a network where your app is deployed. It’s only necessary to integrate Safe Apps SDK for your application.
</Warning>

### 3) Submit your DApp

To submit your DApp to a marketplace, simply click on the submit DApp button. You will be taken to a form where you will fill out the needed information including contract addresses, description, logo, and links. Once your DApp is submitted, the DAppscout team will reach out with any questions and add your DApp to the marketplace.

<Frame>
  <img />
</Frame>


# Multisend
Source: https://docs.blockscout.com/using-blockscout/essential-dapps/multisend

Multisend Essential Dapp

Multisend lets you send ERC20 tokens to multiple addresses at once rather than sending transactions one by one. With just a few clicks, you can create and send bulk transactions automatically, saving significant time and automating the process. Private keys and account information stay secure.

Multisend is useful when distributing tokens to many addresses, for example in an airdrop to a lot of recipients or payroll where you are sending many of the same ERC20 tokens to different addresses.

## Get Started

1. **Connect your wallet** to Blockscout (if needed)

<img alt="DAppscout blockchain explorer interface showing login button and essential dApps including token swap and multisend features" />

2. **Find the Multisend app** in the Essential Dapps Menu

<img alt="DAppscout tutorial showing how to access Multisend dApp: step 1 click DApps menu, step 2 select Multisend to send tokens to multiple addresses" />

3. Click on the token field and **select the token** you want to send.

<img alt="Multisend dApp tutorial step 1: select token address to send tokens to multiple wallet addresses via CSV upload" />

<img alt="Token search modal in Multisend dApp showing CV token selection on Optimism network for bulk token transfers" />

4. **Specify a list of addresses and amounts in CSV format** (for example `0x5c36bd76a6c138187c43da92f66f37e23b4017fa,12`) with 1 address and amount per line. You can upload a .csv file and the box with auto-populate. *Click the 'Show Sample CSV' button to see the formatted example.*

<Warning>
  .eth names are not currently supported, please use full 0x addresses.
</Warning>

<img alt="Multisend dApp CSV upload field for entering multiple recipient wallet addresses to batch send CV tokens" />

<img alt="Multisend dApp with CSV recipient list populated showing wallet addresses and token amounts for batch CV token distribution" />

5. **Click Proceed** to go to the next step, Validation.

<img alt="Multisend dApp with recipient CSV populated and arrow pointing to Proceed button to validate batch token transfer" />

6. In the **Validation** step you will see the amount approved (0 at the moment), the total tokens to be sent, the total number of tokens in the wallet, and the total amount of ETH in the wallet. You will also see the list of recipients and allocations for each address.

<img alt="Multisend validation screen showing transaction summary: 15.4991 CV tokens to be sent to 4 recipients with wallet balances displayed" />

Scroll down to see the approval options. You can either approve the exact token amount for this multisend (recommended) or click unlimited approval. With unlimited you will not need to approve sending for future transactions *(this grants unlimited priviledges to the app, which can be a security risk).*

Click **Approve** and confirm in your wallet.

<img alt="Multisend validation showing recipient list with arrow pointing to Approve button to authorize batch token transfer" />

7. Once you have approved the app to send tokens, you will see the approval transaction in the app. Click **Continue** to go to the third step where you will complete the transaction(s).

<img alt="Multisend validation complete with arrow pointing to Continue button after approving 15.4991 CV token batch transfer to 4 recipients" />

8. **View the total estimate**. You will see an overview along with the cost estimate. You can change the value of gas price with the gear icon, but this can cause issues and is not generally recommended. If everything looks good, click Proceed and sign the transaction(s) in your wallet. There may be multiple transactions to sign depending on the number of recipients.

<img alt="Multisend final step showing transaction summary: 15.4991 CV tokens to 4 recipients with gas cost 0.00134026 ETH and arrow pointing to Proceed button" />

That's it! If you'd like to learn more about Multisender, see the video walkthrough below which goes into more details on the standalone application.

### Multisender video walkthrough

<iframe title="YouTube video player" />


# Revoke
Source: https://docs.blockscout.com/using-blockscout/essential-dapps/revoke

Check, manage and revoke your token approvals

<Warning>
  Revoke is currently being updated for inclusion in Essential Dapps. It will be released shortly.
</Warning>

Many applications require you to grant approvals so that their contracts can interact with tokens in your wallet. This can be a security issue if you have granted unlimited or high allowances, or have granted approvals and forgotten about them. If an application is hacked or misused in some way, this can result in funds being quickly drained from your wallet.

The Revoke app lets you manage your approvals from a single interface. Easily check, update, and revoke token allowances you may have granted to different applications.

## Access the App

Revoke can be accessed directly via the Essential Dapps menu or as an app via the Dappscout interface in Blockscout on supported chains.

<Warning>
  Revoke supports a subset of chains including Ethereum, OP Mainnet, Gnosis, Base and Ink.
</Warning>

<Frame>
  <img alt="" />
</Frame>

## Check and Revoke

1. Select the chain you want to check.

2. Connect the wallet you want to revoke allowances for.

<Frame>
  <img alt="" />
</Frame>

3. Review any allowances and click the Revoke button for those you want to revoke.

<Frame>
  <img alt="" />
</Frame>

4. Confirm the transaction in your web3 wallet. This does not require any gas or transaction fees.

<Frame>
  <img alt="" />
</Frame>

5. Your permissions will update momentarily.

<Frame>
  <img alt="" />
</Frame>

<Frame>
  <img alt="" />
</Frame>

## **FAQ**

<AccordionGroup>
  <Accordion title="Why can't I see the _Value at Risk_ for the approved amount?">
    This usually happens when the price information in USD is not available for a particular token. In these cases, the token amount is displayed without an associated USD conversion.
  </Accordion>

  <Accordion title="Can I revoke multiple approvals at once?">
    Not yet. We're still working on this functionality, and it will be added in future releases.
  </Accordion>

  <Accordion title="Can I use a hardware wallet with Revoke?">
    Yes, you can use any wallet that **WalletConnect** supports.
  </Accordion>

  <Accordion title="Why should I revoke access to my tokens?">
    It's always a good practice to **limit token approvals** when you're not actively using a dapp, especially on **NFT marketplaces**. This reduces the risk of losing funds due to hacks or exploits and helps mitigate the damage caused by phishing scams.
  </Accordion>

  <Accordion title="Why should I use Revoke?">
    Revoke is designed to provide valuable insights about your tokens and account. Instead of only allowing you to revoke token approvals, we offer a **comprehensive overview** of spender accounts. This way, you can make informed decisions and better understand **who has access** to your tokens.
  </Accordion>
</AccordionGroup>

## **Roadmap**

1. **Public Tags**

   We plan to highlight key information about **approved spender contracts**, ensuring users are aware of **who has access** to their tokens. If an approved spender gets hacked or is flagged as a scam, this information will be added to Blockscout, allowing users to react promptly.
2. **Sorting**

   To improve user experience, we're introducing sorting options for approvals. Users will be able to sort approvals by **amount, date, and value at risk**.
3. **Bulk Revoke for Multiple Tokens**

   We're working on adding a **multi-token revoke feature** in upcoming releases to speed up the process.


# Swap
Source: https://docs.blockscout.com/using-blockscout/essential-dapps/swap

Swap and bridge multi-chain application for Blockscout users

Simple swaps and cross-chain bridging transactions are now available via the dedicated Swap app, powered by [LI.FI](http://li.fi/). All swapping and bridging operations are handled by LI.FI’s smart contracts, and their widget provides a flexible and lightweight interface. Blockscout has integrated the LI.FI widget to create a convenient and user-friendly tool specifically for Blockscout users.

<Check>
  Find Swap now under Essential Dapps on your explorer instance. For example, on Ethereum it is located at [https://eth.blockscout.com/essential-dapps/swap](https://eth.blockscout.com/essential-dapps/swap).
</Check>

<img alt="Blockscout Swap Pn" />

## Swap Features

* **Simple interface for swapping and bridging**. Swap is a convenient, easy-to-use tool for your token management and exchange needs. The clean, straightforward interface is designed for fast and intuitive token exchanges.
* **Flexibility with tokens, chains, and addresses**. Swap currently supports operations on 18 blockchains including**Ethereum, Arbitrum, Base, Polygon, Scroll, zkSync, Optimism, Gnosis, Fuse, Lisk, Unichain, Aurora, Immutable, Soneium, Rootstock, Celo, World Chain, and Ink.**  \
  \
  Swap and bridge operations can be initiated by 1 address and sent to the same address or a different address if desired. If the address receiving a token does not have enough gas tokens to cover fees, a portion of the swap can be converted to automatically cover gas costs.
* **Low integrator fees**. Swap offers low fees (.4%). For example, a \$100 swap incurs a \$0.40 fee.
* **Aggregator fetches the best prices**: The application checks across 32 exchanges and 19 bridges to find the best swap and bridge prices, along with options for different routes if you want faster bridging or prefer to use a specific app or bridge.
* **Li.Fi for consistency and security:** Swap uses Li.Fi under the hood to provide swap and bridging functionality. This audited codebase is used throughout the ecosystem and trusted by many projects to provide safe and secure transfers.
* Earn Merits when using Swap. [See this page](/using-blockscout/merits/earn-merits-when-using-swap) to learn more about earning Merits for using your favorite swap and bridge application.

## Swap Operations

### Connect a wallet

Connect your wallet to Blockscout to access Swap functions.

1. Click connect wallet
2. Choose your preferred wallet and connect

### Swap tokens on the same chain

Swap checks up to 32 exchanges and aggregators to find the best routes.

### Swap and bridge tokens from 1 chain to another

Depending on the token and chain there may be several routes. Check routes for pricing and timing that best suits your needs.

### Swap, bridge and send tokens to another wallet

Swap and bridge from one chain to another. To send to a different wallet, click the wallet icon and enter the wallet address where you are sending funds.

<Frame>
  <img alt="" />
</Frame>


# CSV Exports
Source: https://docs.blockscout.com/using-blockscout/export-to-csv

Export of blockchain entities related to address into a CSV file

Export to CSV gives users a way to easily download and analyze blockchain data. It is available for tabs on the address page including transactions, internal transactions, tokens, and logs.

<Info>
  Note: simplified CSV exports (transactions and transfers only, with no ability to define time periods) exist in Blockscout releases up to 3.5.1. Enhanced CSV export is available from v3.5.2+
</Info>

<Frame>
  <img />
</Frame>

You will find the *Download CSV* button under the list of entities related to the tab.

<Frame>
  <img />
</Frame>

<Info>
  *Note:* under the *Tokens* tab, the list of token transfers will be exported.
</Info>

After clicking the button you will be forwarded to a */csv-export* page for a given address and given type of export (transactions, internal-transactions, token-transfers, logs).

<Frame>
  <img />
</Frame>

It is possible to specify an arbitrary period for the data export. By default, the current period is the previous month. After completing the reCaptcha, the data for the chosen period should be exported.

<Frame>
  <img />
</Frame>

<Info>
  *Tip*: In order to prevent hitting a 30 secs loading timeout, choose the smallest time period possible for your data needs.
</Info>


# Merits
Source: https://docs.blockscout.com/using-blockscout/merits



## What are Merits?

<Check>
  To learn details about the program please see our dedicated [Merits announcement blog post](https://blog.blockscout.com/blockscout-merits-rewarding-block-explorer-skills).
</Check>

* Merits are digital rewards that are collected by interacting with Blockscout and participating in various relevant activities.

* Merits do not exist on any single blockchain, but rather are connected to an Externally Owned Account (`0x` address) via the Blockscout dashboard and your web3 wallet.

* Merits can be earned on any chain where the program is supported, and Merits accumulate to an account across blockchains and rollups.

* Merits are designed to make block exploration more fun and engaging, rewarding learning and regular usage.

* Merits do not have any material value, but in the future may unlock access to new features, merchandise, discounts, and other exclusive opportunities and benefits.

* You must login to Merits on Blockscout to see your balance and claim additional Merits.

* You can view more information about your Merits, the leaderboard and badges in the dedicated Merits hub at [https://merits.blockscout.com/](https://merits.blockscout.com/)

The following information relates to using the Blockscout Merits interface. See our [FAQs](/using-blockscout/merits/faqs) for common questions.

<Info>
  Merits are available on a limited number of Blockscout instances to start:

  * [Ethereum Mainnet](https://eth.blockscout.com/)

  * [Ethereum Sepolia](https://eth-sepolia.blockscout.com/)

  * [Ethereum Holesky](https://eth-holesky.blockscout.com/)

  More chains will be added as the program rolls out.
</Info>

## Sign up for Merits

Sign up to start collecting Merits and participating in the program. You will receive 100 Merits for signing up or 200 Merits if you use a referral link/code. There are several ways to signup:

* New account referral signup

* New account signup (no referral)

* Existing account signup

### New account referral signup

We recommend using a referral code to signup as you will receive an additional 100 Merits for a total of 200 Merits. Ask a friend or Blockscout community member (telegram, discord) if you need a code or link.

#### **1) Enter the link you received**

The link will be the instance name followed by `/?ref=XXXXXX` for example [https://eth.blockscout.com/?ref=9V4NUJ](https://eth.blockscout.com/?ref=9V4NUJ)

*Note: if you only have a code and not a link you will enter the code during step 5 of the sign in flow.*

If starting with a referral link you will be forwarded to this page.

<Frame>
  <img />
</Frame>

If using a six digit referral code, you will go to the Blockscout instance and click on the Merits button to get started.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### **2) Connect your wallet (EOA)**

Note that this wallet can be used to collect Merits across chains.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### 3) **Login to account**

Once you have granted permission to connect your wallet, you can login to your account. When confirming in your web3 wallet be sure to check that the site info and wallet info are correct *(in this example we are using a testnet, so the information will be different depending on the instance you are accessing).*

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### 4) **Add email (optional)**

Add your email to enable account watchlist functionality and receive Merit updates.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### 5) Join the Merits program

Your code should pre-populate. Click Get started and confirm sign-in via your web3 wallet.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### 6) Congratulations!

You are now enrolled in the Merits program. You can share your referral link on X, or click Open to view the Merits dashboard.

<Frame>
  <img />
</Frame>

### New account signup (no referral)

We recommend using a referral code to receive additional Merits, however you can signup without one if desired. The flow is the same as the referral sign up with a code. The only difference is you do not toggle the I have a referral code button (step 5 above) to proceed.

<Frame>
  <img />
</Frame>

### Existing Account Signup

If you already have a Blockscout account, you can still use a referral code to sign up for the Merits program. Login to your Blockscout account and paste in the referral link or press the Merits button to start. Follow the process above starting with step 5.

<Frame>
  <img />
</Frame>

## Navigate the Merits dashboard

<Frame>
  <img />
</Frame>

1. **Merits balance and claim**: Displays your current balance and claim eligibility. You can claim 10 Merits 1 time per day. This amount resets the following day. The claim button will also send any available referral Merits to your account. Referral Merits are added when someone you refer completes an activity. Referrals are not available for signing up or daily claims.

2. **Referral data**: Shows how many individuals you have referred to the Merits program.

3. **Streak data *\<coming soon>***: Shows how many days in a row you have claimed your daily Merits.

4. **Referral code and link**: Your referral link and code. Share this code with friends and they will receive additional Merits on signup. You will receive a 10% bonus for rewards earned by your referrals for Blockscout activity. More about referrals is in the [FAQ](/using-blockscout/merits/faqs).

5. **Activity tracking *\<coming soon>***: Tracks your activities and earned Merits for these activities.

6. **Contract verification tracking *\<coming soon>***: Tracks your contract verification activity and related Merits rewards.

7. **Badges *\<coming soon>***: Collection of the Blockscout badges you have earned for completing various Blockscout-based campaigns. For more information, see the [Blockscout Badges site](https://badges.blockscout.com/home).


# Activity Pass
Source: https://docs.blockscout.com/using-blockscout/merits/activity-pass

Get you pass and earn more Merits

<Info>
  Read more about the Activity Pass in this [blog post.](https://www.blog.blockscout.com/earn-rewards-for-block-explorer-routine-activity-pass/)
</Info>

The Activity Pass opens up new opportunities for Blockscout power users! Activity Pass holders can:

* Earn Merits through various activities such as contract verification, contract interaction, using Blockscout apps like [Revokescout](../revokescout.md) and [Swapscout](../swapscout/), and just using Blockscout for exploring the chain.
* Compete against other Activity Pass hodlers for Performance Rank status and benefits
* Access exclusive offers available only to Activity Pass holders.

<img alt="Activity Pass Pn" />

### How it works

Get an Activity Pass, then regular Blockscout usage earns your extra Merits.

1. Activity passes become available periodically on the [Merits hub](https://merits.blockscout.com/). They are available in the **Spend Merits** tab.
2. Purchase a pass using your Merits.
3. Login to Blockscout with your Merits wallet.
4. Complete various actions on Blockscout. Your Merits will increase weekly based on your activity and other user's activity.

Bonus: Activity Pass holders can mint an exclusive NFT on the [Blockscout Badges site](https://app.gitbook.com/s/-MjSwkv4zokqCUebt-98/).

### Activity Pass Actions

The following actions will earn you additional Merits when you have an Activity Pass. You need to be **logged into Blockscout with your Merits address** and **hold an Activity Pass on that address** to qualify.

1. Regular Blockscout usage. Checking addresses, balances, tokens, etc. All the things you normally do on Blockscout earn you more Merits.
2. Using Blockscout-related apps like [Swapscout ](../swapscout/)and [Revokescout](../revokescout.md).
3. Verifying contracts through the Blockscout UI. [This guide](https://www.blog.blockscout.com/how-to-verify-your-smart-contract-with-the-blockscout-ui/) shows a simple example using hardhat.
4. Interacting with contracts on the Blockscout UI. [Use Read and Write methods directly from Blockscout](https://docs.blockscout.com/devs/verification/interacting-with-smart-contracts) to interact with contracts.

### Amount of Merits Earned

Merit earnings for Activity Pass holders are based on your effort vs other Pass holders! The higher you rank in the activity, the more Merits you receive.   Here is the breakdown of **Merits earned per week** for various activities.

* **Blockscout Usage**: Regular usage when logged into Blockscout
* **Contract Verification**: Verifying contracts with the Blockscout UI
* **Interactions**: Swapscout, Revokescout, and Contract Read/Write

|         | Blockscout Usage | Contract Verification | Interactions |
| ------- | ---------------- | --------------------- | ------------ |
| 90%+    | 200              | 400                   | 300          |
| 75%-90% | 160              | 320                   | 240          |
| 50%-75% | 120              | 240                   | 180          |
| 25%-50% | 80               | 160                   | 120          |
| 5%-25%  | 40               | 80                    | 60           |
| >5%     | 10               | 20                    | 15           |

### FAQs

<AccordionGroup>
  <Accordion title="What is an Activity Pass">
    An Activity Pass is an add-on that allows you to earn additional Merits when using Blockscout.
  </Accordion>

  <Accordion title="How do I get my Activity Pass?">
    Activity Passes are available in limited batches via the Merits website. Check back regularly and follow [Blockscout on X ](https://x.com/blockscout) to be informed of new Activity Pass drops.
  </Accordion>

  <Accordion title="Where can I use my Activity Pass? What chains are supported?">
    You can find the full list of Blockscout Explorers eligible for earning Merits by clicking the “Earn” button on an activity card. At the beginning of the program the following instances are supported:

    1. Ethereum Sepolia
    2. Ethereum mainnet
    3. Gnosis Chiado
    4. Gnosis mainnet
    5. Ink mainnet
    6. Soneium mainnet
  </Accordion>

  <Accordion title="What should I do after getting an Activity Pass? Where do I start?">
    Click the “Earn” button to see the list of Blockscout Explorers where you can earn Merits just by using them. You can also check our documentation for details on specific activities that grant Merits.
  </Accordion>

  <Accordion title="How do I receive my earned Merits?">
    Activity Pass Merits are automatically distributed to your account on a **weekly basis.**

    Every Monday, all earned Merits are automatically distributed. At the start of each new week, Performance Ranks and previously earned Merits are reset. New week, new achievements!
  </Accordion>

  <Accordion title="What is Performance Rank?">
    Performance Rank is your position among all users with Activity Passes who are earning Merits. A higher rank means you are among the top users who have earned the most Merits. The higher your Performance Rank, the more Merits you receive.
  </Accordion>

  <Accordion title="How does Performance Rank influence the Merits I receive? ">
    Different Performance Ranks result in different amounts of Merits received on a weekly basis. Completing different activities will also earn you different Merit amounts.

    ***Note: The Merits distribution per Performance Rank may change based on program participation, please stay tuned!***
  </Accordion>
</AccordionGroup>


# Badges
Source: https://docs.blockscout.com/using-blockscout/merits/badges

Earn and collect NFT Scout badges by engaging and exploring the blockchain with Blockscout.

<Frame>
  <img />
</Frame>

<Check>
  Access the Blockscout badges site at [https://badges.blockscout.com](https://badges.blockscout.com/home)
</Check>

### What are Blockscout Badges?

Blockscout Badges are digital rewards (NFTs) that you can earn by participating in Blockscout community activities and campaigns.

### What makes each badge special?

Each badge collection has four rarity levels:

* Common

* Rare

* Super Rare

* Legendary

When you mint a badge, you'll randomly receive one of these rarity levels – like opening a mystery box!

### How do I get a badge?

1. Connect your crypto wallet to the Base network

2. Choose the badge collection you want

3. Click 'Mint' if you're eligible

4. Important: Use the same wallet address you used during the campaign, as this proves your eligibility

After minting, you can see your badge by looking up your wallet address on the [Base Blockscout Explorer.](https://base.blockscout.com/)

### Why can't I get a badge?

Each badge is only available to people who participated in specific campaigns during certain time periods. Don't worry though – Blockscout regularly launches new campaigns! Follow our social media to catch the next one.

### Can I trade or sell my badges?

Yes! You can move your badges to different wallets or sell them on NFT marketplaces.

### How many badges can I get?

You can get one badge per campaign you participate in. Collections typically have a limited number of badges available.

### What can I do with my badge?

Right now, your badge shows that you participated in a Blockscout activity. In the future, badges might give you special access to:

* Events

* Exclusive merchandise

* Other special benefits

### Having problems?

Join the [Blockscout badges Discord channel](https://discord.gg/blockscout) for help with any issues.


# Earn Merits when using Swap
Source: https://docs.blockscout.com/using-blockscout/merits/earn-merits-when-using-swap



### Swap & Merits

Swap allows you to swap assets and bridge assets with a convenient, intuitive interface. In addition, users who are signed up to the [Blockscout Merits program](/using-blockscout/merits) will receive Merits for using Swap. Merits are distributed based on several factors:

1. The total 24-hour volume of Swap transfers.

2. The fees generated based on this volume.

3. The total number of unique Swap users within a 24 hour period.

At the end of each 24 hour period (00:00 UTC to 23:59 UTC each day) the number of transactions and fees generated by each unique address are calculated and Merits are distributed automatically.

### Allocation

A set amount of Merits are marked for distribution each day amongst all qualified users. An address receives a percentage of this amount based on the fees their address generates during that period for swaps and bridge transactions. The more fees an address generates, the higher percentage of Merits they receive from the overall allocation.

### Min/Max

* **Minimum**: The minimum amount of Merits distributed to any address that interacts with Swapscout during a 24 hour period is 1% of the total Merits allocation for the day.

* **Maximum**: The maximum amount of Merits distributed to any one address interacting with Swapscout during a 24 hour period is 10% of the total Merits allocation for the day.

### Distribution

Merits are automatically distributed to each account at the end of each day. You can view your current Merits balance by [logging into Merits](/using-blockscout/merits) on a Blockscout instance where the program is active.


# FAQs
Source: https://docs.blockscout.com/using-blockscout/merits/faqs



We will continue adding frequently asked questions to this list. If you have an issue that needs immediate attention, please ask on the [Blockscout Discord](https://discord.gg/blockscout).

### Merits

<AccordionGroup>
  <Accordion title="Where can I learn more about the Merits program?">
    The blog announcement includes information about the origins of the program, how you can earn Merits, and future directions. [Merits announcement blog post](https://blog.blockscout.com/blockscout-merits-rewarding-block-explorer-skills).
  </Accordion>

  <Accordion title="What chains are Merits available on?">
    Merits will be rolled out to many Blockscout supported chains in the future. Right now they are available on:

    * [Ethereum Mainnet](https://eth.blockscout.com/)

    * [Ethereum Sepolia](https://eth-sepolia.blockscout.com/)

    * [Ethereum Holesky](https://eth-holesky.blockscout.com/)

    Your Merits account is chain agnostic - you can claim Merits and collect referral bonuses on any supported chain.
  </Accordion>

  <Accordion title="How does the daily claim work?">
    The daily claim is worth 10 Merits. You can claim one time per day, and the amount resets to 10 Merits at 0:00 UTC each day. To claim, login to the Dashboard and click the claim button.
  </Accordion>

  <Accordion title="How do I refer someone to the program?">
    In your Merits dashboard you will find a referral code and a referral link you can share with your friends. They can follow the link directly or enter the code when signing up to the program for the first time.
  </Accordion>

  <Accordion title="How do I receive referral rewards?">
    You do not receive referral rewards when someone first signs up using your referral code or claims their daily bonus.

    However, you will receive rewards (10% of the Merits they earn) for block explorer usage or activities/campaigns they complete. These rewards will accumulate to your account, and you can claim to your account with the claim button in the dashboard.

    Activities which earn referral rewards are still in development, and will be listed once they become available.

    Learn more in the [Merits announcement blog post](https://blog.blockscout.com/blockscout-merits-rewarding-block-explorer-skills).
  </Accordion>

  <Accordion title="Where can I use my Merits?">
    Merits are collectible rewards displayed in your Blockscout dashboard. They show your Blockscout adoption, usage, and mastery and promote learning in a gamified way. Right now you don't use them other than to show off your block explorer skills. In the future Merits may unlock access to new features, merchandise, discounts, and other exclusive opportunities and benefits.
  </Accordion>

  <Accordion title="Can I earn Merits using Swapscout">
    Yes you can! Swapscout users who are signed up to the Merits program receive Merits based on their own usage, total usage (how many users use [Swapscout](https://swap.blockscout.com/)) and fees. These Merits are automatically distributed to the account each day at 0:00 UTC. See the [Earn Merits when using Swapscout](/using-blockscout/swapscout/earn-merits-when-using-swapscout)page for more information on this distribution.
  </Accordion>

  <Accordion title="How do streaks work?">
    Streaks are achieved by claiming Merits on consecutive days within a 24 hour span. You can earn additional Merits for longer streaks. Check the [streak rewards](/using-blockscout/merits/streak-rewards) page for more details.
  </Accordion>
</AccordionGroup>

### Badges

<AccordionGroup>
  <Accordion title="What are Badges?">
    Blockscout Badges is a new initiative by the Blockscout Team, designed to celebrate and recognize our community members for their involvement in key campaigns and contributions.
  </Accordion>

  <Accordion title="Are there different traits in each collection?">
    Most Blockscout Badge collections features four distinct rarity levels, giving users an exciting opportunity to mint a legendary NFT. The rarity tiers include Common, Rare, Super Rare, and Legendary, with each mint offering a randomized chance at unlocking the most coveted level.
  </Accordion>

  <Accordion title="How does the minting process work?">
    Minting a Blockscout NFT is quick and simple. Just connect your preferred wallet and switch to the Base network. Select the NFT collection, and if you are eligible to mint you will be able to click on the ‘Mint’ button. Use the same wallet address you used in the relevant campaign, as your eligibility is tied to that specific address. Once minted, you can view and verify your new Blockscout NFT on the Blockscout Explorer by searching your wallet address and exploring the tokens stored in your wallet
  </Accordion>

  <Accordion title="Why am I ineligible?">
    Participants for each NFT were gathered during the designated campaign period. But don’t worry—Blockscout will be launching more NFTs in future campaigns! Be sure to follow our social channels to stay updated on the next exciting opportunity
  </Accordion>

  <Accordion title="Can I transfer or sell badges?">
    Yes! All Blockscout Badges are transferable, allowing you to move them to new wallets or sell them on secondary markets
  </Accordion>

  <Accordion title="Are collections limited in quantity?">
    Most collections are limited, with a maximum of one NFT per participant per campaign.
  </Accordion>

  <Accordion title="What else can I do with a badge?">
    For now your badge is an NFT that proves you completed a certain Blockscout related activity. Show it off with pride! There may be future applications for Blockscout badges like access to events, badge-limited swag or other goodies. Stay tuned for more details.
  </Accordion>

  <Accordion title="What if I am having problems or issues?">
    Please [join our badges discord channel](https://discord.com/invite/blockscout) and we will help troubleshoot your issues or questions
  </Accordion>

  <Accordion title="What Gitcoin rounds are eligible for the initial Gitty up badge?">
    If you donated to previous Gitcoin rounds for Blockscout in 2023 and 2024 you are eligible for the Gitty Up badge. This includes the following rounds:

    * Ethereum Infrastructure: 25 Apr 2023 to 09 May 2023

    * Ethereum Infrastructure: 15 Aug 2023 to 29 Aug 2023

    * Ethereum Core Infrastructure, Research and Development: 15 Nov 2023 to 29 Nov 2023

    * Developer Tooling and Libraries: 23 Apr 2024 to 07 May 2024

    * GG21: 7 August to 22 August 2024

    * Octant Community Round: 12 September to 27 September 2024

    You can check the list of all eligible addresses [join our badges discord channel here](https://discord.com/invite/blockscout)
  </Accordion>
</AccordionGroup>


# Leaderboard
Source: https://docs.blockscout.com/using-blockscout/merits/leaderboard

View accounts by Merits

<Info>
  The Merits leaderboard is a part of the standalone Merits hub website available at [https://merits.blockscout.com/](https://merits.blockscout.com/)
</Info>

The Merits leaderboard displays accounts ordered by the number of Merits each account has earned.

<Frame>
  <img />
</Frame>

* The leaderboard reflects the current season of earnings, and resets when a new season launches.

* Search is only available by the full address, but is not case sensitive.

* Ranking is determined by the number of Merits earned. If addresses share the same number of Merits, they all share the same rank. In this example, all accounts have 352 Merits, and are all ranked 12.

<Frame>
  <img />
</Frame>


# Streak Rewards
Source: https://docs.blockscout.com/using-blockscout/merits/streak-rewards

Connecting to Blockscout on consecutive days increases your streak and your Merits

<Info>
  Available at [https://merits.blockscout.com/](https://merits.blockscout.com/) and on the Blockscout Merits dashboard.
</Info>

<Frame>
  <img />
</Frame>

Earn additional Merits by visiting and claiming once per day. A day starts at 00:00 UTC and ends at 23:59 UTC.

<Info>
  To maintain a streak, you must make a claim each calendar day. The timing on the claim doesn't matter, it can occur any time between 00:00 UTC and 23:59 UTC.
</Info>

* Merits must be claimed once per day to maintain a streak. Every day you make a Merits claim, your streak increases by 1.

* If you fail to make a claim on a calendar day, your streak resets to 0.

* Every 7 days of a streak results in an increased Merit reward. This is a single day award which can is claimed each 7th day of your streak (7,14,21,28 etc).

* Currently, the highest reward is 20 Merits, for a total of 30 Merits (10 daily claim Merits + 20 streak reward Merits) available to claim on streak reward days.

<Info>
  *See the table below for more details on streak rewards.*
</Info>

### Streak rewards for daily claims

| Streak | Daily Claim | Reward | Total Merits Claim |
| ------ | ----------- | ------ | ------------------ |
| 1-6    | 10          | 0      | 10                 |
| 7      | 10          | 10     | 20                 |
| 8-13   | 10          | 0      | 10                 |
| 14     | 10          | 20     | 30                 |
| 15-20  | 10          | 0      | 10                 |
| 21     | 10          | 20     | 30                 |
| 22-27  | 10          | 0      | 10                 |
| 28     | 10          | 20     | 30                 |


# My Account
Source: https://docs.blockscout.com/using-blockscout/my-account



The My Account feature provides the ability to watch addresses (and receive email notifications regarding activity), create private tags, add API keys to an account and more.

It does not contain any private key info or allow you to withdraw funds. It is designed as an organization and personalization tool for the block explorer, giving you additional ways to customize the data you want to receive.

You can sign up for an account using either an email or your Github credentials.

The following options are currently available:

* **Watch list:** Watch specific addresses and receive email notifications for transactions.

* **Private Tags**: Private tags for addresses & transactions

* **Public Tags**: Request a public category tag displayed to all Blockscout users. Requests are processed manually.

* **API keys:** Add to receive an individually rate limited key.

* **Custom ABI**: Useful for testing & debugging, can be used with verified or unverified contracts.

* **Verified Addresses**: Verify ownership of a smart contract address to easily update information in Blockscout

* **Sign Out**: Sign out, info kept in local storage for easy sign-in.

Additional future features include an upcoming redesign and multi-chain rollout.

## Get Started

<Check>
  *The following example is created using the *[*Optimism Blockscout instance*](https://optimism.blockscout.com/)*.*
</Check>

#### 1) Click the MyAccount Icon

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

#### 2) Sign in / Create an Account

a. Sign in with your existing email and password

b. Create a new blockscout account with an email/password

c. Sign in with an existing github account

<Frame>
  <img />
</Frame>

#### 2a) Email and Password

Enter a valid email and password to setup an account. You will receive a validation notice to your email, be sure to check spam filters as it will come from *[noreply@blockscout.com](mailto:noreply@blockscout.com)*.

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  <img />
</Frame>

<Frame>
  <img />
</Frame>

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  <img />
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#### 2b) Github

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  <img />
</Frame>

#### 3) View Options

Once logged in, you can view options in the My Account Dropdown or on the activated toolbar.

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  <img />
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# API keys
Source: https://docs.blockscout.com/using-blockscout/my-account/api-keys



API Keys are available to enhance request availability. Keys give users the ability to query the API up to 10 requests/sec.

A maximum of 3 keys can be created for each account.

## Create API key

**1) Login to My Account in Blockscout** \<[*login instructions*](/using-blockscout/my-account)> to get started. Once logged in:

1. Go to API keys in the user menu.
2. Press Add API key.

<Frame>
  <img alt="" />
</Frame>

**2)** **Fill in the Name field**. Add a Name for your API key. This is for your information only and to differentiate between different keys. Press **Generate API key.**

<Frame>
  <img alt="" />
</Frame>

**3) API key generated.** The API Key is now added to your API dashboard. You can copy the key or edit the name/delete the key at any time. In addition you can add 2 additional keys (up to 3 per account).

<Frame>
  <img alt="" />
</Frame>

## Use API key

Add the following to the end of a query to use your API key: `&apikey=your-api-key`

For example, a query to get more info on USDT on Optimism with the API key `fdbfa288-1695-454e-a369-4501253a120`would be formatted as follows:

`https://optimism.blockscout.com/api?module=token&action=getToken&contractaddress=0x94b008aA00579c1307B0EF2c499aD98a8ce58e58&apikey=fdbfa288-1695-454e-a369-4501253a120`

<Info>
  For more info on RPC calls see the [RPC API Endpoints documentation](/devs/apis/rpc).
</Info>


# Custom ABI
Source: https://docs.blockscout.com/using-blockscout/my-account/custom-abi



The Custom ABI feature is useful for debugging and testing newly deployed smart contracts. This feature can be used with verified or unverified contracts.

Once a custom ABI is added, the user can test methods using the `Write Custom` feature.

## Add Custom ABI

**1) [Login to My Account](/using-blockscout/my-account)** in Blockscout to get started. Once logged in:

1. Go to **Custom ABI** in the My Account menu.

2. Press the **Add Custom ABI** button.

<Frame>
  <img />
</Frame>

**2)** **Fill in the fields**.

1. **Smart Contract Address**. Enter the correct `0x` address of the deployed contract.

2. **Project Name**. Create a name for your own reference.

3. **Custom ABI**: Copy and paste in the ABI for the contract from your development environment (truffle, hardhat, remix etc) or if the contract is verified you can copy from Blockscout.

4. Press **Create custom ABI**.

<Frame>
  <img />
</Frame>

**3) Custom ABI added** to the home screen. You can edit or remove current custom ABIs or add additional custom ABIs from here.

<Frame>
  <img />
</Frame>

## Interact with a Custom ABI

You will need to be logged into My Account to interact with your custom ABIs. Once you added, you can visit the contract to interact with the custom ABI.

1. Go to the contract page.

2. You will see a Write custom button.

3. Connect your wallet to interact with the contract.

4. Write to the available methods.

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  <img />
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# For Developers
Source: https://docs.blockscout.com/using-blockscout/my-account/for-developers

When setting up My Account for your chain

Please see [My Account settings in configurations](/setup/configuration-options/my-account-settings) for notes about setting up the proper variables and linking to your airtable.


# Private tags
Source: https://docs.blockscout.com/using-blockscout/my-account/private-tags



Private tags help customize your Blockscout instance to track addresses and transactions that are important to you. You can track specific addresses, either EOAs (Externally Owned Addresses) or smart contracts, as well as group and organize specific transactions.

Use the private tags feature to add your own **address tags** and **transaction tags**. These will be viewable on your instance of Blockscout only.

When logged in, a small grey tag is added with the selected name to any specified addresses or transactions. You can also add emojis 😁 for easy identification.

Use cases might include tags for specific wallet accounts (EOAs) of interest, Gnosis safe multisig wallets to highlight, tags for specific applications, tags for specific transaction types, tokens, NFTs etc.

<Check>
  *The following example is created using the *[*Optimism Blockscout instance*](https://optimism.blockscout.com/)*.*
</Check>

<Info>
  To start with private tags, you must first [login to My Account](/using-blockscout/my-account).
</Info>

### 1) Create a Private Address Tag

1. Go to Private Tags in the My Account user menu. Address tag will be the default option

2. Press the **Add address tag** button.

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  <img />
</Frame>

**2)** **Fill in the fields**.

1. Address. Double check you are entering the correct address for the chain. Search the address in Blockscout to confirm.

2. Name. Create a name for the tag (35 characters or less). Emojis are a nice way to differentiate and add style and color to tags.

3. Press **Add tag**.

<Frame>
  <img />
</Frame>

**3) Address tag added** to the Address Tags home screen. You can add additional tags or remove old tags from here.

<Frame>
  <img />
</Frame>

**4) View tags in Blockscout**. They will appear in grey next to additional tags that may exist for that address.

<Info>
  Note, you must be logged in to My Account to see your private tags.
</Info>

<Frame>
  <img />
</Frame>

## 2) Create a Private Transaction Tag

* Go to **Private Tags** in the My Account user menu. Select the **Transaction** tab.

* Press the **Add transaction tag** button.

<Frame>
  <img />
</Frame>

**2)** **Fill in the fields**.

1. Transaction hash. Double check you are entering the correct tx for the chain. Search the transaction and copy/paste from Blockscout to easily add.

2. Name. Create a name for the tag (35 characters or less). Emojis are a nice way to differentiate and add style and color to tags.

3. Press **Add tag**.

<Frame>
  <img />
</Frame>

**3) Transaction tag added** to the transaction tags home screen. You can add additional tags or remove old tags from here.

<Frame>
  <img />
</Frame>

**4) View tags in Blockscout**. They will appear in grey next to additional tags that may exist for that address.

<Info>
  Note, you must be logged in to My Account to see your private tags.
</Info>

<Frame>
  <img />
</Frame>


# Public tags
Source: https://docs.blockscout.com/using-blockscout/my-account/public-tags

Request a tag or report an incorrect tag

Request a public tag for your project's contracts on the public Blockscout instance. Tags appear in search, help create brand awareness for projects, and make exploration easier.

Once submitted, tags are reviewed and accepted/denied manually by the instance admin. If accepted, the tag is added to the public instance. It is also possible to report incorrect public tags through the public tags section.

<Check>
  *The following example is created using the *[*Optimism Blockscout instance*](https://optimism.blockscout.com/)*.*
</Check>

## Request Public Tags

**1) Login to** [**My Account**](/using-blockscout/my-account)

1. Go to **Public tags** in the My Account Menu

2. Press **Request to add public tag**.

<Frame>
  <img />
</Frame>

**2)** **Fill in the fields**. Fields with \* are required.

* Your name\*

* E-mail\*

* Company name

* Company website

* Select either:

  1. I want to add tags for my project

  2. I want to report an incorrect public tag

* Public tags\*: 2 tags max, 35 character max per tag, use the ; as a separator

* Smart contract / Address (0x...)\*: Provide the 0x address of the contract. If you have several, press the "+" to add.

* Reason and Description\*: Add any relevant details and include your color preference for the tags. Include any other helpful or clarifying information here.

<Frame>
  <img />
</Frame>

**3) Public tag request added** to the Public tags home screen. You can edit, request additional tags or delete old tags from here. Public tags are reviewed manually and can take some time in the queue. If your tag request appears in the dashboard it has been successfully submitted and will be reviewed in the order in which it was received.

<Frame>
  <img />
</Frame>


# Verified Addresses
Source: https://docs.blockscout.com/using-blockscout/my-account/verified-addresses



Verify ownership of a smart contract address to easily update information in Blockscout. To verify your ownership, a contract must be deployed on the chain and [verified](/devs/verification).

You will sign a single message to verify contract ownership. Once verified, you can update token information, address name tags, and address labels from the Blockscout console.

1\) **Login to My Account in Blockscout** \<[*login instructions*](/using-blockscout/my-account)>.

1. Go to the **Verified addrs** menu item.

2. Click **Add address**.

<Frame>
  <img />
</Frame>

<Info>
  More info coming soon
</Info>


# Copy and Sign Message
Source: https://docs.blockscout.com/using-blockscout/my-account/verified-addresses/copy-and-sign-message



<Info>
  Instructions coming soon
</Info>


# Watch list
Source: https://docs.blockscout.com/using-blockscout/my-account/watchlist



<Check>
  *The following example is created using the *[*Optimism Blockscout instance*](https://optimism.blockscout.com/)*.*
</Check>

Sign up for email notifications for different actions related to an EOA or contract address. This can include incoming/outgoing transactions for native tokens, ERC-20 tokens or NFTs like ERC-721 and ERC-1155s.

1\) **Login to My Account in Blockscout** \<[*login instructions*](/using-blockscout/my-account)>. From the Watchlist menu click Add address.

<Frame>
  <img />
</Frame>

2\) **Fill in information** including:

* **Address**: 0x address of the EOA or contract to watch.

* **Private tag**: For your reference, will be displayed as a private tag for your Blockscout instance when you are logged in (emoji's accepted 🙂)

* **Notification types**: Select which types of transactions you would like to receive email notifications for. These include native tokens (in this case ETH), ERC-20 tokens, and NFT tokens.

* **Email Notifications**: Select to receive.

* **Add address**: Click button to add to your watchlist.

<Frame>
  <img />
</Frame>

3\) A new address along with an info overview will be added to your watchlist dashboard. You can edit info, remove, or add more items.

<Frame>
  <img />
</Frame>

4\) Click the address to view in the Blockscout console. Watch list addresses show the private tag when logged into My Account.

<Frame>
  <img />
</Frame>

5\) If selected, you will receive emails based on actions completed by this address.

<Frame>
  <img />
</Frame>


# UI Sections
Source: https://docs.blockscout.com/using-blockscout/overviews



Blockscout is a full-featured explorer with many uses. A block explorer provides views and insights into various data stored on chain. Depending on the page, section and instance, different types of data is displayed. See below for different views and learn how to navigate blockchain data.

Blockscout offers different informational displays depending on the page, section and instance you are viewing. Learn more about different views and data displays in Blockscout:

* [Top Menu](/using-blockscout/overviews/top-menu)
* [Blocks](/using-blockscout/overviews/blocks)
* [My Account](/using-blockscout/my-account)


# Address Page
Source: https://docs.blockscout.com/using-blockscout/overviews/address-page

Address page details

# Exploring EOA Addresses on Blockscout

Blockscout provides comprehensive information about Externally Owned Accounts (EOA) on Ethereum and other EVM-compatible blockchains. This guide breaks down the sections of a Blockscout address page using Vitalik Buterin's address (0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045) as an example.

## What is an EOA Address?

An Externally Owned Account (EOA) is a wallet address controlled by a private key, as opposed to a smart contract address. EOAs can initiate transactions, hold ETH and tokens, and interact with smart contracts.

<img alt="Address Page Jp" />

## Section A: Address Header & Identification

### Address Information

| Field                          | Description                         | Example                                    | Purpose                           |
| :----------------------------- | :---------------------------------- | :----------------------------------------- | :-------------------------------- |
| **ENS Name (when applicable)** | Ethereum Name Service domain        | vitalik.eth                                | Human-readable address identifier |
| **Address Hash**               | 42-character hexadecimal identifier | 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 | Unique blockchain address         |
| **Copy Button**                | Click to copy address               | 📋                                         | Quick clipboard access            |
| **QR Code**                    | Visual representation of address    | QR icon                                    | Easy mobile wallet scanning       |
| **Star Button**                | Add to favorites/watchlist          | ⭐                                          | Personal tracking                 |
| **Public Name Tag**            | Community-assigned label            | "Vitalik Buterin"                          | Identity verification             |
| **Additional Tags**            | Category labels                     | "EOA", "Gitcoin Grantee"                   | Classification information        |

### Action Buttons

| Button           | Description                    | Function                           | Use Case                           |
| :--------------- | :----------------------------- | :--------------------------------- | :--------------------------------- |
| **40+**          | ENS names owned by the address | Open to show other ENS properties  | ENS usage                          |
| **5**            | Verify in other environments   | Explore address on other explorers | Address credibility & transparency |
| **Tag Menu (⋯)** | Add tags                       | Add public & private tags          | Tagging                            |

## Section B: Navigation Tabs

### Tab Overview

| Tab                      | Description                     | Content Type                | Purpose                  |
| :----------------------- | :------------------------------ | :-------------------------- | :----------------------- |
| **Details**              | Basic address information       | Balance, tokens, statistics | Primary account overview |
| **Transactions 50+**     | All blockchain transactions     | Incoming/outgoing transfers | Transaction history      |
| **Token transfers 50+**  | ERC-20/ERC-721 movements        | Token-specific activity     | Asset tracking           |
| **Tokens 50+**           | Token holdings                  | Current token balances      | Portfolio overview       |
| **Internal txns 50+**    | Contract-generated transactions | Smart contract interactions | Advanced activity        |
| **Coin balance history** | ETH balance over time           | Historical balance data     | Balance tracking         |
| **Coin balance history** | ETH balance over time           | Historical balance data     | Balance tracking         |

## Section C: Address Details

### Basic Information

| Field                   | Description                     | Value Example                | Significance        |
| :---------------------- | :------------------------------ | :--------------------------- | :------------------ |
| **Balance**             | Current ETH holdings            | 4.77725266 ETH (\$16,037.91) | Available funds     |
| **Tokens**              | Number of different tokens held | >153 (>\$9,680,718.59)       | Portfolio diversity |
| **Net worth**           | Total portfolio value           | >\$9,696,756.50              | Overall wealth      |
| **Transactions**        | Total transaction count         | 73,149                       | Activity level      |
| **Transfers**           | Token transfer count            | 282,412                      | Token activity      |
| **Gas used**            | Total gas consumed              | 789,854,535                  | Network usage       |
| **Last balance update** | Most recent activity            | Block 22933842               | Freshness indicator |

### Token Holdings Details

| Element              | Description             | Format                  | Purpose                |
| :------------------- | :---------------------- | :---------------------- | :--------------------- |
| **Token Count**      | Number of unique tokens | ">153"                  | Portfolio size         |
| **Total Value**      | USD value of all tokens | ">\$9,680,718.59"       | Portfolio worth        |
| **Dropdown Arrow**   | Expand token list       | ▼                       | View individual tokens |
| **Multichain Badge** | Cross-chain presence    | "Multichain" with icons | Multi-network activity |

## Section D: Advanced Features

### Special Indicators

| Feature              | Description            | Appearance              | Meaning                        |
| :------------------- | :--------------------- | :---------------------- | :----------------------------- |
| **ENS Integration**  | Domain name display    | "vitalik.eth"           | Verified identity              |
| **Verified Status**  | Authentication markers | Checkmarks/badges       | Trusted account                |
| **Multichain Data**  | Cross-network presence | Chain icons             | View Multi-blockchain activity |
| **Gas Optimization** | Efficiency suggestions | "Save 32% with GasHawk" | Cost reduction tips            |

### Action Capabilities

| Action               | Description       | Access Method | Result                  |
| :------------------- | :---------------- | :------------ | :---------------------- |
| **Copy Address**     | Copy to clipboard | Copy button   | Address in clipboard    |
| **View QR Code**     | Generate QR code  | QR button     | Mobile-friendly display |
| **Add to Watchlist** | Personal tracking | Star button   | Monitoring setup        |
| **Share Address**    | Social sharing    | Share options | Public distribution     |

## Section E: Activity Analysis

### Understanding Address Metrics

| Metric Range                  | Activity Level | Interpretation      | Example          |
| :---------------------------- | :------------- | :------------------ | :--------------- |
| **0-100 transactions**        | Light user     | Occasional activity | Personal wallet  |
| **100-1,000 transactions**    | Regular user   | Consistent activity | Active trader    |
| **1,000-10,000 transactions** | Heavy user     | High activity       | Power user       |
| **10,000+ transactions**      | Power user     | Very high activity  | Vitalik (73,149) |

### Token Holdings Analysis

| Token Count       | Portfolio Type | Risk Level | Example              |
| :---------------- | :------------- | :--------- | :------------------- |
| **1-10 tokens**   | Conservative   | Low        | Basic portfolio      |
| **10-50 tokens**  | Moderate       | Medium     | Diversified investor |
| **50-100 tokens** | Aggressive     | High       | DeFi enthusiast      |
| **100+ tokens**   | Experimental   | Very High  | Vitalik (153+)       |

### Net Worth Categories

| Value Range            | Wealth Level  | Classification       | Significance           |
| :--------------------- | :------------ | :------------------- | :--------------------- |
| **\<\$1,000**          | Small holder  | Retail investor      | Learning/testing       |
| **\$1,000-\$10,000**   | Medium holder | Active investor      | Serious participation  |
| **\$10,000-\$100,000** | Large holder  | Significant investor | Substantial commitment |
| **\$100,000+**         | Whale         | Major investor       | Market influence       |

**Note:** This guide is based on Vitalik Buterin's address (0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045) as viewed on Blockscout. Address information and values are subject to change as blockchain activity continues.


# Beacon Chain Withdrawal Views
Source: https://docs.blockscout.com/using-blockscout/overviews/beacon-chain-withdrawal-views

Coming Soon

Validator withdrawals will soon be activated on the Ethereum mainnet with the Shanghai/Capella hardfork ([EIP-4895](https://eips.ethereum.org/EIPS/eip-4895)), and Blockscout will provide views for partial and full withdrawals.

Withdrawals are akin to simple transactions (though they are actually 0 gas balance increases) included in the block structure. Coins are transferred from a validator to a preset withdrawal address (either EOA or contract). Each withdrawal also includes a unique integer index starting from 0 and incrementing by 1 with each withdrawal.

The unique `index`, assigned `validatorIndex`, withdrawal receiving `address`, and `amount` are all included in the withdrawals structure and will be displayed on Blockscout on the block and addresses pages.

```json theme={null}
 "withdrawals": [
            {
                "index": "0xbd8d0",
                "validatorIndex": "0x81e",
                "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                "amount": "0x6dcf0a644000"
            },
            {
                "index": "0xbd8d1",
                "validatorIndex": "0x81f",
                "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                "amount": "0x6dcf0a644000"
            },
        ],
```

<Accordion title="Example block with withdrawal struct">
  ```json theme={null}
  {
      "jsonrpc": "2.0",
      "id": 1,
      "result": {
          "baseFeePerGas": "0x7",
          "difficulty": "0x0",
          "extraData": "0x",
          "gasLimit": "0x1c9c380",
          "gasUsed": "0x0",
          "hash": "0x5262de0c24b0cab3fdc32fadda1904f4698ab0b12d505bf733cf47cb3e60f7f7",
          "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
          "miner": "0xf97e180c050e5ab072211ad2c213eb5aee4df134",
          "mixHash": "0x08471cc3dbac65574f049af479631af782cf31c841710640ed615dc50670b378",
          "nonce": "0x0000000000000000",
          "number": "0xd62f",
          "parentHash": "0xdabf9e7ebfad879ad44270c2a7a5ff8e848e72316def4d5b0305f2a1216089f7",
          "receiptsRoot": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
          "sha3Uncles": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
          "size": "0x465",
          "stateRoot": "0x9f2a690353b6d8cfa75cb12347104f42d38463471cda1293696a6c3b685aa839",
          "timestamp": "0x63af29e4",
          "totalDifficulty": "0x1",
          "transactions": [],
          "transactionsRoot": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
          "uncles": [],
          "withdrawals": [
              {
                  "index": "0xbd8d0",
                  "validatorIndex": "0x81e",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d1",
                  "validatorIndex": "0x81f",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d2",
                  "validatorIndex": "0x820",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d3",
                  "validatorIndex": "0x821",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d4",
                  "validatorIndex": "0x822",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d5",
                  "validatorIndex": "0x823",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d6",
                  "validatorIndex": "0x824",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x651c03f6de00"
              },
              {
                  "index": "0xbd8d7",
                  "validatorIndex": "0x825",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d8",
                  "validatorIndex": "0x826",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8d9",
                  "validatorIndex": "0x827",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8da",
                  "validatorIndex": "0x828",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x1a2950b4af800"
              },
              {
                  "index": "0xbd8db",
                  "validatorIndex": "0x829",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8dc",
                  "validatorIndex": "0x82a",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8dd",
                  "validatorIndex": "0x82b",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8de",
                  "validatorIndex": "0x82c",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              },
              {
                  "index": "0xbd8df",
                  "validatorIndex": "0x82d",
                  "address": "0xe7c180eada8f60d63e9671867b2e0ca2649207a8",
                  "amount": "0x6dcf0a644000"
              }
          ],
          "withdrawalsRoot": "0xb28f757020474ee478a03be8ca4a2efaa7ebddbf565129bb08202ce9a8670d44"
      }
  }
  ```
</Accordion>

## UI display examples

### Block page example

<Frame>
  <img />
</Frame>

### Address page example

<Frame>
  <img />
</Frame>


# Blocks
Source: https://docs.blockscout.com/using-blockscout/overviews/blocks



Blocks update on the homepage as they are created with basic information including block number (block height), number of transactions in the block, and time since the block was created.

Click on a specific block number for information about that block, or **View All Blocks** for a more detailed overview of recent blocks.

The all blocks page can also be accessed from the top menu.

<Info>
  Blockscout displays are configurable and may show different information depending on the instance and/or consensus method. These examples use a V1 instance of the UI. **V2 views are in process.**
</Info>

<Frame>
  <img />
</Frame>

## View All Blocks

The view all blocks page shows updated details from the most recent blocks. Use the page arrows to navigate

<Frame>
  <img />
</Frame>

#### Details by line

1. Number of transactions in the block / size of block in bytes / time since block was created.

2. Validator appending the block to the chain (fee recipient).

3. Reward to validator (in ETH). Equals the amount of priority fees sent by users to include transactions in the block.

4. Same as (3).

5. Portion of tx fee (in ETH) burned due to EIP-1559. Amount burned = `baseFeePerGas * gasUsed`

6. Block Gas limit. On Ethereum this is 30M gas: 2x the target size of 15M.

7. Amount of gas used in the block (amount and % of block space used). The blue line visualizes the %.

## Individual Block Page

Click on a block number (this number, also referred to as block height, indicates how many blocks have been added to the chain) to view additional details about the block. Scroll down to view individual transactions contained in a block.

Click on the tooltip (i) next to each item to view relevant info.

<Frame>
  <img />
</Frame>

1. **Block Height**: Also known as block number, shows the position of the block on the chain.

2. **Timestamp**: Time & date the block was produced.

3. **Transactions**: Number of transactions included in the block.

4. **Fee Recipient**: Address of the validator (block producer) that received priority fees. Copy the address with the blue icon and paste into search to find more details about this validator.

5. **Size**: Size of the data contained in the block in bytes.

6. **Hash**: Cryptographic hash of the block header.

7. **Parent Hash**: Hash of the preceding block.

8. **Difficulty**: *NA for PoS. W*ork required to mine a block in PoW.

9. **Total Difficulty**: *NA for PoS.* Total difficulty to mine the chain up until this block.

10. **Gas Used**: Total amount of gas used in the block & % of filled space.

11. **Gas Limit**: Total gas limit for the block. 30M is Ethereum limit, which represents 2x the 15M target.

12. **Nonce**: *N/A for PoS*. Demonstrates work in PoW.

13. **Base Fee per Gas**: Minimum multiplier required for a transaction to be included in a block.

14. **Burnt Fees**: Amount of ETH burned in the block.

15. **Priority Fee/Tip**: Total tips for transactions included in the block

16. **Miner Reward**: Amount received by fee recipient in PoS. Matches (15).

Scroll below the block details to view transactions contained within the block.

<Frame>
  <img />
</Frame>


# Glossary of Terms
Source: https://docs.blockscout.com/using-blockscout/overviews/glossary-of-terms



<Info>
  Under Construction
</Info>

## Block Explorer Glossary

**Address**: A unique identifier for a wallet or smart contract on the blockchain.

**Block**: A group of transactions that have been verified and added to the blockchain.

**Block Height**: The number of blocks in the chain between any given block and the first block (genesis block).

**Contract**: Also known as a smart contract, it's a self-executing program stored on the blockchain.

**Gas**: The unit of measure for the computational work required to execute transactions or smart contracts on Ethereum.

**Gas Price**: The amount of cryptocurrency you're willing to pay per unit of gas for a transaction.

**Hash**: A unique fixed-length string of characters that represents data. In blockchain, it's used to identify blocks and transactions.

**Miner/Validator**: Entities that verify and add new transactions to the blockchain.

**Nonce**: A number used once, typically to verify the uniqueness of transactions.

**Pending Transaction**: A transaction that has been broadcast to the network but not yet included in a block.

**Token**: A type of cryptocurrency that represents a tradable asset or utility and is often built on top of an existing blockchain.

**Transaction**: The transfer of cryptocurrency or data between addresses on the blockchain.

**Transaction Fee**: The cost to process a transaction on the blockchain, typically paid to the chain miners or validators.

**Wallet**: A tool that allows users to store, send, and receive cryptocurrency.

*Note: Specific terms may vary slightly depending on the blockchain network and the block explorer being used.*


# Main Menu
Source: https://docs.blockscout.com/using-blockscout/overviews/top-menu



## V2 UI

<Check>
  *The following views are taken from the* [*Optimism Blockscout instance*](https://optimism.blockscout.com/)*.*
</Check>

### Network Menu

Shows available Mainnet and Testnets.

<Frame>
  <img />
</Frame>

### Blockchain Menu

Access transactions, blocks, batches and L1 \<-> L2 data.

<Frame>
  <img />
</Frame>

### API Menu

Access API information including the REST API which serves the v2 UI.

<Frame>
  <img />
</Frame>

## V1 UI

Many projects still use the previous Blockscout UI, and info below relates to the previous v1 UI. We encourage projects to [upgrade to the new U](/setup/deployment/frontend-migration)I.

## Top Menu

The top menu contains navigational items for exploration. The menu is customizable, and different instances can have different menus depending on the needs of the chain.

<Frame>
  <img />
</Frame>

<Frame>
  <img />
</Frame>

## Blocks

* **Blocks:** Access high-level data for blocks, beginning with the most recent.
  <Frame>
    <img />
  </Frame>

* **Uncles:** Not valid for PoS consensus (but available for PoW consensus chains such as Ethereum Classic), uncles are created when 2 blocks are mined at the same time. Only 1 block can be added to the chain, and Uncles are the blocks that are not added, but miners still receive rewards for these blocks.

* **Forked Blocks (Reorgs):** Blocks which are not included in the primary chain due to chain reorganizations.

## Transactions

* **Mined**: Transactions which have been added to the chain, either by validators or miners depending on the chain type.

* **Pending**: Transactions still in the mempool which are waiting to be mined. These transactions may be mined or excluded depending on gas fees or network congestion.

## Tokens

Token menu is often configured differently depending on the instance.

* **All:** A list of ERC-20 tokens deployed to the chain.

* **Native** (ie **ETH** on mainnet): Displays native token holders, ordered by balance.

* **Bridged**: If a chain includes bridged tokens (ie [Gnosis Chain](https://gnosis.blockscout.com/)) these can be catalogued here.

## APIs

* **GraphQL**: Explore API calls using GraphQL and the in-browser IDE. Learn more about the [GraphQL Blockscout integration here](/devs/apis/graphql).

* **RPC**: API supporting GET and POST requests for many different API calls.

* **Eth RPC**: Supports the most popular [JSON RPC methods.](https://ethereum.github.io/execution-apis/api-documentation/)

## Apps

Customizable menu that can link to different ecosystem applications, utilities and statistics. [Gnosis Chain](https://gnosis.blockscout.com/) currently has the most robust example of the Apps menu.

<Frame>
  <img />
</Frame>

## Networks

The current network name along with a dropdown displaying available instances. Self-hosted chains may choose to only show their Mainnet and testnets. Hosted instances typically include links to other Hosted instances including Ethereum, Ethereum Classic, and Gnosis Chain.

## Night Mode

Switch to a dark background using the night-mode toggle.

<Frame>
  <img />
</Frame>

## Search Bar

The comprehensive search bar allows for search by address, token name, token symbol, transaction hash, block number, tag or project name. It is typically the easiest way to find data quickly, and populates with inline results as you type.

## Custom Project Logo

Also included in the top menu is the Project logo. Projects can add and change custom logo using ENV variables during deployment. [More info here](/setup/configuration-options/branding-configs).

<Frame>
  <img />
</Frame>


# Transaction Fields
Source: https://docs.blockscout.com/using-blockscout/overviews/transaction-fields

Description of your new file.

# Blockscout Transaction Fields Reference Guide

Example transaction on Ethereum

<img alt="<img src=&#x22;blocksBlockscout Ethereum transaction details page showing 0.0019 ETH transfer from Huobi Deposit Funder 7 to wallet address, with transaction hash, block confirmations, timestamp, and navigation tabs for token transfers, logs, and state changes" />

## Transaction Summary (Header)

| Field                   | Description                            | Format/Example                         | Purpose                                |
| :---------------------- | :------------------------------------- | :------------------------------------- | :------------------------------------- |
| **Transaction Summary** | Quick overview of transaction action   | "⚡ Transfer 0.0019 ETH to 0x1e...2988" | Instant understanding of what happened |
| **Transaction Icon**    | Visual indicator of transaction type   | Lightning bolt (⚡) for transfers       | Quick visual identification            |
| **Amount Display**      | Primary value being transferred        | "0.0019 ETH"                           | Main transaction amount                |
| **Recipient Address**   | Shortened destination address          | "0x1e...2988" with copy button         | Quick recipient identification         |
| **View Counter**        | Number of times transaction was viewed | "👁 8"                                 | Shows transaction popularity/interest  |

## Transaction Overview Fields

| Field                 | Description                                       | Format/Example                                                | Purpose                                                   |
| :-------------------- | :------------------------------------------------ | :------------------------------------------------------------ | :-------------------------------------------------------- |
| **Transaction Hash**  | Unique identifier for this specific transaction   | 66-character hex string starting with "0x"                    | Transaction's "receipt number" for tracking and reference |
| **Status and Method** | Current state and transaction type                | ✅ Success                                                     | Shows whether transaction completed successfully          |
| **Block**             | Block number and confirmations                    | 22933572                                                      | Show BlockNumber                                          |
| **Timestamp**         | When transaction was mined with confirmation time | 🕐 8m ago                                                     | Reflects timestamp: Jul 16 2025 12:33:59 PM (-06:00 UTC)  |
| **Sponsored**         | Advertisement or sponsored content section        | Ad banner with "Advertise to" message                         | Supports open source block explorer                       |
| **From**              | Sender address with label                         | "🔴 Huobi: Deposit Funder 7" with copy button                 | Identified sender (exchange, contract, etc.)              |
| **To**                | Recipient address                                 | 🟡 0x1ec7cB3FE99bD07E6faBa7D296857bCC102988" with copy button | Destination address                                       |

## Blockscout-UI Features

| Feature                      | Description                              | Location                 | Purpose                              |
| :--------------------------- | :--------------------------------------- | :----------------------- | :----------------------------------- |
| **Transaction Summary Line** | Quick overview with icon and key details | Top of page              | Instant understanding of transaction |
| **View Counter**             | Shows transaction popularity             | Next to summary          | Community interest indicator         |
| **Address Labels**           | Known entity identification              | From/To fields           | Better context than raw addresses    |
| **Sponsored Content**        | Advertisement section                    | Middle of details        | Revenue for block explorer           |
| **Copy Buttons**             | Quick copy functionality                 | Next to addresses/hashes | User convenience                     |
| **Tabbed Navigation**        | Organized information sections           | Below summary            | Easy access to different data types  |
| **Color-Coded Status**       | Visual status indicators                 | Status field             | Quick success/failure identification |
| **Confirmation Speed**       | Time to confirmation                     | Timestamp field          | Network performance insight          |

## Navigation Tabs

| Tab                 | Description                    | Contents                                   | Purpose                                 |
| :------------------ | :----------------------------- | :----------------------------------------- | :-------------------------------------- |
| **Details**         | Main transaction information   | Hash, status, block, addresses, gas, value | Primary transaction data                |
| **Token transfers** | ERC token movements            | Token name, amount, from/to addresses      | Track token transfers separate from ETH |
| **User operations** | Account abstraction operations | User operation details for AA wallets      | Advanced wallet interactions            |
| **Internal txns**   | Internal transactions          | Contract-to-contract calls                 | See all sub-transactions                |
| **Logs**            | Event logs from contracts      | Contract events and their data             | Smart contract activity                 |
| **State**           | State changes                  | Storage and balance modifications          | What changed on the blockchain          |
| **Raw trace**       | Complete execution trace       | Step-by-step execution details             | Debug and analysis                      |

## Visual Elements and Icons

| Element               | Description                | Meaning                            | Context                     |
| :-------------------- | :------------------------- | :--------------------------------- | :-------------------------- |
| **⚡ Lightning Icon**  | Transaction type indicator | Fast/standard transaction          | Used in transaction summary |
| **🔴 Red Circle**     | Address label indicator    | Exchange or known entity           | Huobi exchange identifier   |
| **🟡 Yellow Circle**  | Address label indicator    | Contract or user wallet            | Regular address marker      |
| **✅ Green Checkmark** | Success status             | Transaction completed successfully | Status indicator            |
| **👁 Eye Icon**       | View counter               | Number of page views               | Popularity metric           |
| **📋 Copy Button**    | Copy to clipboard          | Click to copy address/hash         | User convenience            |
| **🕐 Clock Icon**     | Timestamp indicator        | Time-related information           | Timing reference            |

## Transaction Details Fields

| Field               | Description                                              | Format/Example                   | Purpose                                                   |
| :------------------ | :------------------------------------------------------- | :------------------------------- | :-------------------------------------------------------- |
| **From Address**    | Wallet address that initiated the transaction            | Labeled address with copy button | Identifies the sender with context                        |
| **To Address**      | Destination address for the transaction                  | Labeled address with copy button | Identifies recipient with context                         |
| **Value**           | Amount of native currency (ETH) transferred              | ETH amount with USD equivalent   | Shows direct ETH transfer (separate from token transfers) |
| **Transaction Fee** | Total cost paid to miners/validators                     | ETH amount with USD equivalent   | Total processing cost                                     |
| **Nonce**           | Sequential counter for transactions from sending address | Number (e.g., 1,247)             | Prevents replay attacks and ensures ordering              |

## Gas Information Fields

| Field                | Description                                      | Format/Example                               | Purpose                                            |
| :------------------- | :----------------------------------------------- | :------------------------------------------- | :------------------------------------------------- |
| **Gas Limit**        | Maximum gas the sender was willing to pay        | Number (e.g., 21,000)                        | Upper bound on computational work                  |
| **Gas Used**         | Actual gas consumed by the transaction           | Number with percentage (e.g., 21,000 (100%)) | Actual computational work performed                |
| **Gas Price**        | Price per unit of gas                            | Gwei amount (e.g., 20.5 Gwei)                | Cost per unit of computation                       |
| **Max Fee Per Gas**  | Maximum fee willing to pay per gas unit (Type 2) | Gwei amount (e.g., 25 Gwei)                  | EIP-1559 fee mechanism for predictable fees        |
| **Max Priority Fee** | Maximum tip willing to pay to miners (Type 2)    | Gwei amount (e.g., 2 Gwei)                   | Incentivizes miners to include transaction quickly |
| **Base Fee Per Gas** | Network's base fee at transaction time (Type 2)  | Gwei amount (e.g., 18.5 Gwei)                | Burned portion of fee (not given to miners)        |

## Transaction Type Fields

| Field                | Description                            | Format/Example                 | Purpose                                    |
| :------------------- | :------------------------------------- | :----------------------------- | :----------------------------------------- |
| **Transaction Type** | EIP standard used for this transaction | Type 0, Type 1, Type 2         | Indicates fee mechanism and features       |
| **Type 0**           | Legacy transactions                    | Standard format                | Original transaction format                |
| **Type 1**           | EIP-2930 (Access List)                 | With access list               | Gas optimization for contract interactions |
| **Type 2**           | EIP-1559 (Dynamic Fee)                 | With base fee and priority fee | More predictable fee mechanism             |
| Type 3               | EIP-4844<br />(Blobs)                  | Blob carrying transaction      | Accomodate batched data                    |

## Input Data Fields

| Field                    | Description                                 | Format/Example                | Purpose                                       |
| :----------------------- | :------------------------------------------ | :---------------------------- | :-------------------------------------------- |
| **Input Data**           | Data payload sent with transaction          | Hexadecimal string            | Contains function calls and parameters        |
| **Method ID**            | First 4 bytes identifying contract function | 4-byte hex (e.g., 0xa9059cbb) | Identifies which contract function was called |
| **Input Data (Hex)**     | Raw hexadecimal data                        | 0x followed by hex characters | Raw transaction data                          |
| **Input Data (UTF-8)**   | Human-readable text format                  | Plain text (when applicable)  | Readable version of data                      |
| **Input Data (Decoded)** | Function calls with parameter names         | Function name and parameters  | User-friendly view of contract interactions   |

## Token Transfer Fields

| Field              | Description                           | Format/Example            | Purpose                                |
| :----------------- | :------------------------------------ | :------------------------ | :------------------------------------- |
| **Token Name**     | Name of the transferred token         | Text (e.g., "USD Coin")   | Identifies the token being transferred |
| **Token Symbol**   | Token's ticker symbol                 | Text (e.g., "USDC")       | Short identifier for the token         |
| **Token Amount**   | Quantity of tokens transferred        | Number with decimals      | Amount being moved                     |
| **Token Type**     | Standard used for the token           | ERC-20, ERC-721, ERC-1155 | Indicates token functionality          |
| **From Address**   | Token sender address                  | 42-character hex string   | Who sent the tokens                    |
| **To Address**     | Token recipient address               | 42-character hex string   | Who received the tokens                |
| **Token Contract** | Address of the token's smart contract | 42-character hex string   | Contract managing this token           |

## Event Logs Fields

| Field                | Description                      | Format/Example          | Purpose                            |
| :------------------- | :------------------------------- | :---------------------- | :--------------------------------- |
| **Log Index**        | Sequential numbering of events   | Number (e.g., 0, 1, 2)  | Order of events within transaction |
| **Contract Address** | Address that emitted the event   | 42-character hex string | Source of the event                |
| **Event Name**       | Name of the emitted event        | Text (e.g., "Transfer") | Type of event that occurred        |
| **Topics**           | Indexed event parameters         | Array of hex strings    | Searchable event data              |
| **Data**             | Non-indexed event data           | Hex string              | Additional event information       |
| **Decoded Logs**     | Human-readable event information | Structured data         | User-friendly view of events       |

## State Changes Fields

| Field               | Description               | Format/Example          | Purpose                      |
| :------------------ | :------------------------ | :---------------------- | :--------------------------- |
| **Address**         | Account that changed      | 42-character hex string | Which account was modified   |
| **Storage Changes** | Before and after values   | Hex values              | What data changed in storage |
| **Balance Changes** | ETH balance modifications | ETH amounts             | How balances changed         |
| **Nonce Changes**   | Account nonce updates     | Number changes          | Transaction counter updates  |

## Status Indicators

| Status      | Visual Indicator | Meaning                             | Next Steps                            |
| :---------- | :--------------- | :---------------------------------- | :------------------------------------ |
| **Success** | Green checkmark  | Transaction completed successfully  | Transaction is final                  |
| **Failed**  | Red X            | Transaction failed during execution | Check revert reason, retry if needed  |
| **Pending** | Orange clock     | Transaction waiting to be mined     | Wait for confirmation or increase gas |
| **Dropped** | Gray indicator   | Transaction removed from mempool    | Resubmit with higher gas price        |

## Additional Information Fields

| Field                   | Description                           | Format/Example          | Purpose                          |
| :---------------------- | :------------------------------------ | :---------------------- | :------------------------------- |
| **Block Hash**          | Unique identifier for the block       | 66-character hex string | Reference to containing block    |
| **Block Timestamp**     | When the block was mined              | UTC timestamp           | Block creation time              |
| **Transaction Receipt** | Proof of transaction processing       | JSON data               | Technical execution details      |
| **Raw Transaction**     | Complete transaction data             | JSON format             | Developer-level transaction info |
| **Revert Reason**       | Error message for failed transactions | Text description        | Explains why transaction failed  |

## Common Transaction Patterns

| Pattern                  | From Address | To Address     | Value   | Input Data        | Tokens Transferred |
| :----------------------- | :----------- | :------------- | :------ | :---------------- | :----------------- |
| **Simple ETH Transfer**  | User wallet  | User wallet    | > 0 ETH | Empty/minimal     | None               |
| **Token Transfer**       | User wallet  | Token contract | 0 ETH   | Function call     | Token amount       |
| **Contract Interaction** | User wallet  | Contract       | 0 ETH   | Function data     | Possibly tokens    |
| **Contract Creation**    | User wallet  | null           | 0 ETH   | Contract bytecode | None               |
| **Multi-token Transfer** | User wallet  | Contract       | 0 ETH   | Function call     | Multiple tokens    |

## Troubleshooting Guide

| Issue                     | Possible Causes                       | What to Check                                              |
| :------------------------ | :------------------------------------ | :--------------------------------------------------------- |
| **Transaction Not Found** | Wrong hash, wrong network, too recent | Verify hash, check network, wait for indexing              |
| **Failed Transaction**    | Out of gas, revert, invalid input     | Check gas limit, read revert reason, verify input          |
| **High Gas Fees**         | Network congestion, complex operation | Check gas price, simplify transaction, wait for lower fees |
| **Pending Too Long**      | Low gas price, network issues         | Increase gas price, check network status                   |
| **Wrong Token Amount**    | Decimal confusion, display issue      | Check token decimals, verify actual amount                 |

**Quick Reference:** Use Ctrl+F to search for specific field names in this guide. All fields are organized by the section they appear in on the Blockscout transaction page.


# Transaction Types
Source: https://docs.blockscout.com/using-blockscout/overviews/transaction-types



Different types of transactions are categorized in the Blockscout UI to allow for quick identification. Types include:

* **Blob txn:** 4844-type transactions which include large amounts of data
* **Coin transfer**: value transfer, value >= 0, no tx input
* **Contract call**: tx input is present (any value including 0)
* **Contract creation**: creation of a smart-contract
* **Token burning**: recognized token transfer of any of ERC-20, 721, 1155 token instance (single or bulk) to 0x0000... address
* **Token creation**: creation of token instance in ERC-1155
* **Token minting**: token transfer of any of ERC-20, 721, 1155 token instance (single or bulk) from 0x0000... address
* **Token transfer**: token transfer of any of ERC-20, 721, 1155 token instance (single or bulk)
* **Transaction**: A contract call where the contract has not yet been identified by Blockscout.

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# Token Support
Source: https://docs.blockscout.com/using-blockscout/token-support



Blockscout supports the following token types:

* ERC-20: Fungible tokens

  * Standard for interchangeable tokens

  * Used for cryptocurrencies, stablecoins, utility tokens

* ERC-721: Non-fungible tokens (NFTs)

  * Unique, indivisible tokens

  * Often used for digital art, collectibles, game items

* ERC-1155: Multi-token standard

  * Combines fungible and non-fungible tokens

  * Efficient for gaming and complex ecosystems

* ERC-777: Advanced fungible tokens (basic indexing but no additional views, provides similar info to ERC-20)

  * Adds features like operator support and hooks

  * Backward compatible with ERC-20.

* ERC-4626: Tokenized Vaults (basic indexing but no additional views, provides similar info to ERC-20)

  * Standard for yield-bearing tokens

  * Used in DeFi for lending and yield farming


# ERC 1155 Support
Source: https://docs.blockscout.com/using-blockscout/token-support/erc-1155-support

Basic support for ERC-1155s

[ERC-1155](https://eips.ethereum.org/EIPS/eip-1155) contracts are designed to support multiple token types within a single contract. This standard is being adopted rapidly for efficiency and optimization, and is being used to bundle multi-token transactions and approvals while supporting both fungible and non-fungible tokens.

Recognition and labelling for ERC-1155 contracts, indexing instance balances for both fts and nfts, parsing single and batched transactions, and monitoring and displaying minting events are included.

## GnosisChain Example

ERC-1155s are supported for the Gnosis Chain and any new ERC-1155 instances are recognized on deployment. For ERC-1155 contracts created prior to the enhanced support, a new single or batched transfer, mint, or token instance creation triggers contract recognition.

[https://gnosis.blockscout.com/token/0x93d0c9a35c43f6BC999416A06aaDF21E68B29EBA?tab=token\_transfers](https://gnosis.blockscout.com/token/0x93d0c9a35c43f6BC999416A06aaDF21E68B29EBA?tab=token_transfers)

<img alt="Unique One ERC1155" />


# Widgets
Source: https://docs.blockscout.com/using-blockscout/widgets

Quick access to essential 3rd party address and contract info

<Tip>
  If your project would like to incorporate a widget into the explorer, please [contact us in Discord](https://discord.gg/blockscout). Learn more -> [Widgets Deck](/images/widgets-deck.pdf)
</Tip>

## Overview

Blockscout Widgets deliver contextual data from third-party protocols directly on address and contract pages. Essential information about onchain identity, activity, security amd ecosystem participation provides a broad overview of relevant information.

<img alt="Example blockscout Address Widget" />

## Viewing Widgets

1. Navigate to any externally owned account (EOA) address, ENS name (like [vitalik.eth](https://eth.blockscout.com/address/0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045)) or contract (i.e. the  [UniV2 factory contract](https://eth.blockscout.com/address/0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f)) in your Blockscout explorer.
2. Scroll down to the Widgets section below the address/contract details to view widgets.
3. You can also view via the **Widgets tab** for any address or contract, which will show all available widgets.

<img alt="Address Details" />

## Key Features

### Enhanced Address Insights

Widgets display engagement and activity across the Web3 ecosystem, providing a holistic view beyond basic balances and transactions.

### Security & Risk Assessment

For contracts and tokens, widgets surface risk scores, audit information, complexity metrics, and other security analytics.

### Ecosystem Integration

Blockscout integrates with multiple protocols. Additional details are provided in the Available Widgets section.

**Address Pages**

* **Talent Protocol:** Onchain creator score
* **Drops**: Airdrop checker
* **GitPOAP**: Contributor reward badges
* **Blockscout Badges**: Minted Blockscout badges
* **Ethereum Follow Protocol (EFP)**: Onchain social graph
* **EtherScore**:  Onchain reputation badges
* **Webacy**: Risk analysis
* **Human Passport**: Humanity verificaiton
* **Humanode**: Onchain biomapper

**Contract Pages**

* **Webacy**: Risk score
* **Trustblock**: Audit info
* **SmartMUV**: Contract Complexity

## Supported Networks

Widgets are available on Blockscout hosted chains including:

* Ethereum Mainnet
* Optimism
* Base
* Arbitrum
* Celo
* Gnosis
* Soneium
* Polygon

## Benefits

### For Users

* Comprehensive onchain identity view
* Quick access to ecosystem participation data
* Security assessment at a glance
* Airdrop eligibility tracking

### For Developers

* Contract complexity analysis
* Audit verification
* Risk assessment tools
* Integration opportunities

### For the Ecosystem

* Enhanced transparency
* Improved security awareness
* Stronger protocol integrations
* Better user experience

## Currently Available Widgets

Widgets show an overview score. Each widget can be clicked on to reveal additional details.

### Address Page Widgets

#### Creator Score

**Source:** Talent Protocol

Measures a content creator's reputation by analyzing data from various platforms. The Creator Score evaluates both quantity and quality of work using verifiable data points, providing comprehensive assessment of a creator's influence and trustworthiness.

**Additional available details:**

* Overall creator score
* Platform-specific scores (Farcaster, Lens, etc.)
* Total earnings
* Content quality metrics

#### Drops

**Source:** Drops (Airdrop Checker)

Automatically identifies unclaimed crypto airdrops by monitoring wallet addresses across multiple networks. Shows eligibility for recent and verified airdrops.

**Additional available details:**

* Eligible airdrops
* Claimable amounts
* Claimed rewards history
* Airdrop status

**Features:**

* Multi-network monitoring
* Telegram alerts for new airdrops
* Real-time eligibility checking

#### GitPOAP

**Source:** GitPOAP

Rewards and permanently records contributions to open-source projects via GitHub using the POAP (Proof of Attendance Protocol) model. Provides public, permissionless, onchain verification of open-source contributions.

**Additional available details:**

* Total GitPOAPs earned
* Project contributions
* Contribution history
* GitHub integration status

#### Blockscout Badges

**Source:** Blockscout Merits

Limited-edition NFT badges celebrating community involvement in Blockscout campaigns and contributions.

**Additional available details:**

* Earned merits
* Referral count
* Activity streaks
* Collectible NFT badges

#### EFP Followers

**Source:** Ethereum Follow Protocol (EFP)

Onchain social graph protocol for Ethereum accounts that complements ENS. Enables users to follow or tag other addresses through NFT lists, creating a decentralized social network.

**Additional available details:**

* Follower count
* Following list
* Recent transactions
* Social connections

#### Onchain Achievement Badges

**Source:** EtherScore

Represents onchain achievements completed across DeFi protocols, NFT platforms, and DAOs. Each badge signifies a specific milestone or activity in Web3.

**Additional available details:**

* Total badge count
* Badge categories
* Achievement progress
* Protocol integrations

#### Address/Contract Risk Score (available for both)

**Source:** Webacy

Numerical assessment evaluating potential security threats, compliance issues, or suspicious activities associated with a wallet address.

**Additional available details:**

* Overall risk rating (Low/Medium/High)
* Suspicious activity flags
* Security warnings
* Risk analysis details

**Purpose:**

* Assess wallet security status
* Identify potential threats
* Provide security insights

#### Humanity Score

**Source:** Gitcoin Passport

Proof-of-personhood system using verifiable credentials ("stamps") from trusted web2 and web3 sources to verify humanity without compromising privacy. Helps distinguish real humans from bots and Sybil attacks.

**Additional available details:**

* Unique Humanity Points
* HUMN Points
* Collected stamps
* Verification status

**Stamp Sources:**

* Government ID
* Biometrics
* ENS domains
* Social profiles
* Other verified credentials

#### Biomapper Score

**Source:** Humanode

Biomapper is an on-chain, private facial recognition tool that provides Sybil resistance by ensuring each verified person can link only one EVM-compatible address to a dApp

**Additional available details:**

* Humanode biomapper verification status

**Purpose:**

* Shows if a user is verified with biomapper, proving they are a unique human via facial recognition.

### Contract Page Widgets

#### Audits

**Source:** Trustblock

Displays verified smart contract audits recorded onchain through Trustblock, a web3 protocol for audit transparency.

**Requirements:**

* Auditors and audit firms must publish contracts on Trustblock for audits to appear

**Additional available details:**

* Audit status
* Auditor information
* Audit reports
* Verification details

#### Complexity Score

**Source:** SmartMuv Explorer

Evaluates the structural complexity of a smart contract's storage layout. Primarily intended for developers and auditors who need to understand, migrate, or upgrade smart contracts safely.

**Additional available details:**

* Layout summary
* Deep analysis
* Complexity score
* Storage structure breakdown

**Use Cases:**

* Contract migration planning
* Upgrade safety assessment
* Security auditing
* Development review