> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.bigcommerce.com/_mcp/server.

# Module 2: Key Architecture

> Build amazing commerce solutions powered by the BigCommerce platform

## Docs

- [React and Next.js](https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/react-nextjs.md)
- [Routing](https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/routing.md)
- [The API Client](https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/api-client.md)
- [Components and Theming](https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/components.md)
- [Performance Checklist](https://docs.bigcommerce.com/developer/learn/courses/catalyst-core/architecture/performance.md)