data-loading

Define a loader function on the route that returns your data, then consume it in the component with Route.useLoaderData or getRouteApi for code-split files. The loader runs in parallel with component preloading during route matching.

loaderDeps maps validated search params into the loader cache key, so the loader re-runs only when those deps change. Return only the relevant params, not the whole search object, to avoid unnecessary reloads from unrelated param changes.

Loaders are client-first and run in the browser by default. With TanStack Start SSR they also run on the server, so server-only code like database queries must go inside a server function called from the loader.

The default staleTime is 0, so data is always considered stale and reloads in the background on every route re-match. Set a staleTime in milliseconds on the route or defaultStaleTime on the router to keep data fresh longer.

Call router.invalidate() from your errorComponent instead of reset(). Invalidation re-runs the loader and resets the error boundary, while reset only clears the boundary UI and leaves the stale loader error in place.