Blockchain data indexing turns raw on-chain data into a database you can query quickly. A blockchain node is built to validate and serve blocks, not to answer questions such as "all trades of this token in the last hour" or "every wallet that bought in its first minute". An indexer reads blocks, transactions and events as they arrive, decodes them, and stores them in a structure that an application, dashboard or trading system can query in milliseconds.
Why a Node Alone Is Not Enough
- Event queries over large block ranges are slow and limited by RPC providers.
- Nodes do not aggregate: no volumes, candles, holder counts or rankings.
- Data from multiple contracts and chains has to be combined in your own model.
How an Indexer Works
- Ingest new blocks and logs from one or more RPC endpoints, websocket streams or, on Solana, Geyser plugins.
- Decode events and calls with the contract ABIs (or program layouts) into typed records: swaps, transfers, mints, liquidity changes.
- Store and aggregate in a database, with rollups per time frame, from seconds to months.
- Handle reorgs: blocks near the chain tip can be replaced, so the indexer tracks confirmations and rolls back data from orphaned blocks.
- Backfill history from the contract's deployment block, and replay safely when the data model changes.
- Serve the data through a REST or GraphQL API, websocket feeds or alerts.
Hosted Subgraphs or a Custom Indexer?
Subgraphs on The Graph and similar hosted indexers are a quick way to make one protocol's events queryable. A custom indexer fits better when you need low latency for trading, data across many chains or protocols, heavy aggregations, or full control over cost and uptime. We build custom indexers in Rust for throughput and reliability.
Typical Applications
- Detecting new token launches and liquidity pools as they appear.
- Price, volume, buyer and seller metrics per token over any time frame.
- Portfolio and position tracking, and data for trading tools and DeFi dashboards.
- Real-time feeds for alerts and bots, built on event listeners.
Frequently Asked Questions
How fast is indexed data available?
For live data, typically within moments of the block being produced. The trade-off is how many confirmations you wait for before treating data as final.
Can you index historical data?
Yes. A backfill processes history from the deployment block onward, after which the indexer follows the chain tip.
Which chains can be indexed?
Any EVM chain and Solana. Each chain has its own data sources and finality rules, which the indexer must respect.
Who owns the code?
Ownership of the source code is set out in the contract, and the code can be fully yours, including documentation and tests.
Part of our blockchain development work. See also on-chain trading bots.
Build Your Blockchain Data Pipeline
Tell us which chains, contracts and metrics you need, and how fast. We will design an indexer and API that keep up with the chain.