How does Remix's data flow architecture compare to traditional React apps?

Traditional React apps use useEffect + fetch + useState (or React Query) for data — each component manages its own loading state. Remix completely replaces this pattern. In Remix, the URL is the source of truth: Each route URL has a loader that fetches all data needed for that UI. No client-side data fetching on mount — loaders run on the server (or via fetch on navigation). No loading spinners for initial data — data is available before the page renders. Automatic cache invalidation: after a mutation (action), Remix re-runs all loaders — no manual cache updates. Parallel loading: all loaders in the route hierarchy run in parallel, not in a tree of sequential useEffects. Error handling: errors in loaders surface to ErrorBoundary, not try/catch in useEffect. This architecture eliminates most client-side data fetching complexity — no loading/error/data state management, no race conditions, no stale cache issues. The trade-off: this pattern requires server-side routing and doesn't map directly to offline-first apps.