> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sqd.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Build an Indexer from Scratch

> Learn to compose SDK packages into a complete indexer

An indexer built with the Squid SDK (a *squid*) is an ordinary Node.js project. Building one from scratch means initializing an npm package, installing the SDK packages you need — a Fuel data source for retrieving and filtering the raw data, a [data store](../reference/data-stores/typeorm-store) for saving the processed records, and optionally the [GraphQL server](../reference/openreader/overview) — then wiring them together in a short `main.ts`. See the [packages overview](../reference/packages-overview) for the full list of building blocks.

For a complete walkthrough of developing a Fuel squid, follow the dedicated tutorial:

<Card title="Indexing Fuel receipts" icon="graduation-cap" href="./indexing-receipts">
  Build a Fuel indexer that tracks contract receipts step by step.
</Card>