route-handler-design

To design a Next.js App Router route handler for webhooks, implement `route.ts` exports that read the raw body using `request.text` or `arrayBuffer` to verify signatures before returning an explicit success status code like 200.

Use Next.js Route Handlers when the caller is an external client such as a mobile app, third-party integration, or server-to-server webhook, whereas Server Actions are better suited for typed UI form submissions.

The best way to configure CORS in a Next.js Route Handler is to export an explicit `OPTIONS` method function that sets the appropriate `Access-Control-Allow` headers, alongside enforcing consistent header behavior for external callers.

Control caching and runtime selection in a Next.js API endpoint by applying segment config exports such as `dynamic`, `revalidate`, and `runtime` in your `route.ts` file to override default GET caching behavior.

Yes, you can stream binary downloads and large responses in a Next.js Route Handler by returning a Web-standard `ReadableStream` within the Response object for efficient data transfer.

Reading the request body twice in a Next.js route handler fails because Web-standard Request streams can only be consumed once, requiring you to buffer the raw body if multiple reads are needed for parsing and verification.