> For the complete documentation index, see [llms.txt](https://docs.lightlink.io/lightlink-protocol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lightlink.io/lightlink-protocol/tools-for-developers/data-indexers.md).

# Data Indexers

### The Graph

[The Graph](https://thegraph.com/) is the most popular blockchain indexing solution to simplify data delivery. The Graph indexes blockchain data based on subgraph descriptions and allows for effectively querying and filtering data with GraphQL.

[Official documentation](https://thegraph.com/docs/en/about/)

### Envio

[Envio](https://envio.dev/) is a self-hosted indexer for custom EVM chains. It is a simple tool to index data from your dApp and to use it to track stats or deliver data to the frontend.

[Official documentation](https://docs.envio.dev/docs/overview)

### Flair

[Flair](https://docs.flair.dev/) is a free indexing solution for maintaining an indexed database of filtered transactions for any EVM chain.

[Official documentation](https://docs.flair.dev/)


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