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Open Ethereum Indexer

Open Ethereum Indexer is a flexible and modular blockchain indexing service that allows you to index, query, and monitor Ethereum (or any other EVM-compatible chain) blockchain data. It provides a modular architecture for building applications that need to track and/or index blockchain events and transactions.

It is designed to allow you to quickly build a custom blockchain monitoring solution with support for indexing without having to worry about the technical details of blockchain monitoring and indexing.

Why Use Open Ethereum Indexer?

Building blockchain applications often requires tracking on-chain events and state changes. Open Ethereum Indexer provides:

  • A ready-to-use infrastructure for monitoring blockchain activity
  • Real-time blockchain event tracking and backfilling from a historical block
  • Postgres database for storing indexed data
  • Customizable event and block handlers
  • Optional API and GraphQL endpoints for querying indexed data
  • Modular architecture for easy extension and customization
  • Support for any network (including custom networks) that conforms to the Ethereum JSON RPC Specification (opens in a new tab)
  • Monitoring and metrics with Prometheus

Technical Architecture

Open Ethereum Indexer is built on NestJS (opens in a new tab), providing a dependency-injected application that's easy to extend. It connects to an Ethereum node via JSON-RPC and processes blocks and events as they occur on the blockchain.

Data is stored in PostgreSQL, allowing for efficient querying and retrieval of indexed information. The app uses TypeORM (opens in a new tab) to interact with the database which should be used for any database operations inside event handlers too.

Use Cases

Open Ethereum Indexer is ideal for:

  • DeFi applications that need to track token swaps, deposits, or other financial events
  • NFT marketplaces requiring indexing of transfers and sales
  • DAOs that want to monitor governance events
  • Applications that want to be notified if on-chain events meeting specific criteria occur
  • Any application that needs to store, query and analyze on-chain data

Getting Started

Check out the Getting Started guide to get started with Open Ethereum Indexer and see the examples.

Contributing

We welcome contributions! Please see our Contributing Guide for details.

Getting Started