App Router File Conventions Next.js 16 Notes - Use for request-boundary logic. is deprecated in Next.js 16. - runs on the Node.js runtime and cannot be configured for Edge. - Keep matchers narrow. Exclude , static files, and image assets unless the route explicitly needs proxy logic. - Route Handlers in are the right fit for health checks, webhooks, backend-for-frontend endpoints, and server-only proxy calls. Server Components (Default) Server Actions Data Fetching Caching and Revalidation - Use for route-level invalidation after mutations. - Use when data fetches share a cache tag across rou…