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Flair

Real-time and historical custom data indexing for any evm chain.

Flair offers reusable indexing primitives (such as fault-tolerant RPC ingestors, custom processors, re-org aware database integrations) for receiving, transforming, storing, and accessing your onchain data.

Flair architecture

Why Flair?

  • 🚀 A parallel and distributed processing paradigm, rather than constrained sequential processing, supports your indexing stack's scalability and resiliency.
  • 🧩 Focused on primitives, which means on the left you plug in an RPC and on the right you output the data to any destination database.
  • 🚄 Native real-time stream processing for certain data workloads (such as aggregations, rollups) for things like total volume per pool, or total portfolio per user wallet.
  • ☁️ Managed cloud services avoid DevOps and irrelevant engineering costs for dapp developers.
  • 🧑‍💻 Avoid decentralization overhead (consensus, network hops, etc.). We believe the best UX for dapps reading data must be as close to the developers as possible.

Features

  • ✅ Listen to any EVM chain with just an RPC URL.
    • Free managed RPC URLs for 8+ popular chains already included.
    • Works with both websocket and https-only RPCs.
  • ✅ Track and ingest any contract for any event topic.
    • Auto-track new contracts deployed from factory contracts.
  • Custom processor scripts with Javascript runtime (with Typescript support)
    • Make external API or Webhook calls to third-party or your backend.
    • Get current or historical USD value of any ERC-20 token amount of any contract address on any chain.
    • Use any external NPM library.
  • Stream any stored data to your destination database (Postgres, MongoDB, MySQL, Kafka, Elasticsearch, Timescale, etc).

Get started

  1. Clone the starter boilerplate template and follow the instructions:
git clone https://github.com/flair-sdk/starter-boilerplate.git
# ... follow instructions in README.md
info

Boilerplate instructions will create a new cluster, generate an API Key, and set up a manifest.yml to index your first contract with sample custom processor scripts.

Learn more about the structure of manifest.yml.

  1. Configure Linea RPC nodes. Set a unique namespace, Linea chainId and RPC endpoint in your config. Remember that you can add up to 10 RPC endpoints for resiliency.
{
"cluster": "dev",
"namespace": "my-awesome-linea-indexing-dev",
"indexers":
[
{
"chainId": 59140,
"enabled": true,
"ingestionFilterGroup": "default",
"processingFilterGroup": "default",
"sources": [
# Having at least 1 websocket endpoint is highly recommended
"wss://linea-mainnet.infura.io/v3/xxxxxxxxxx",
"https://linea-mainnet.infura.io/v3/xxxxxxxxxx",
# You can add multiple endpoints for failover
"https://rpc.linea.build",
],
},
],
}
  1. Sync some historical data using the backfill command. Remember that the enabled: true flag in your config already enables your indexer to capture data in real-time.
# backfill certain contracts or block ranges
pnpm flair backfill --chain 59140 --address 0x0872ec4426103482a50f26ffc32acefcec61b3c9 -d backward --max-blocks 10000
# backfill for a specific block number, if you have certain events you wanna test with
pnpm flair backfill --chain 59140 -b 409652
# backfill for the recent data in the last X minute
pnpm flair backfill --chain 59140 --min-timestamp="30 mins ago" -d backward
  1. Query your custom indexed data.

  2. Stream the data to your own database.

Examples

Explore real-world usage of Flair indexing primitives for various use cases.

DeFi

NFT

Need help?

Our engineers are available to help you at any stage.

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