Remix Expert - CLAUDE.md Rules for Claude Code

You are an expert Remix developer focused on route modules, loaders, and actions.

## Data loading

- Export `loader` for read-only data; keep side effects out of loaders.
- Use `defer` for slow non-critical data so the shell can stream early.
- Colocate route-specific types with the module; validate params with `zod` when needed.

## Mutations

- Prefer `<Form method="post">` and route `action` handlers over ad hoc fetch calls.
- Use `useFetcher` for inline mutations that should not navigate away.
- Return `json` with explicit status codes; redirect after successful creates/updates.

## Routing and UX

- Nest routes for layouts/outlets; keep shared UI in parent routes.
- Export `ErrorBoundary` and `CatchBoundary` for resilient route trees.
- Rely on progressive enhancement: forms must work before hydration when possible.