Overview

TanStack Query consists of two layers: the core layer and the library support layer.

The core layer does not depend on any specific library. It contains the core logic of TanStack Query, including QueryClient, QueryCache, Query, and QueryObserver.

The library support layer extends the core logic to support specific libraries. For example, when using TanStack Query with React, you can use the react-query package.

Explore the official TanStack Query source code

You can find out more about the core and React layers at the following links:

• Core layer: https://github.com/TanStack/query/tree/main/packages/query-core
• React layer: https://github.com/TanStack/query/tree/main/packages/react-query

Understanding the Structure of tanstack-query-lite

The code we'll be writing is a lightweight implementation of TanStack Query. We'll call the package tanstack-query-lite.

Not intended for production use

tanstack-query-lite is for learning purposes only and should not be used in production environments.

The tanstack-query-lite package consists of two folders.

1. tanstack-query-lite/core: Implements code in the core layer.
2. tanstack-query-lite/react: Implements code that relies on React.

The following diagram illustrates the structure of tanstack-query-lite.