Clerk Auth

This covers the essential Clerk patterns you need for Next.js App Router projects: setting up ClerkProvider, protecting routes with middleware, and accessing auth state in server components. The middleware guidance is solid, emphasizing a single root file and createRouteMatcher for route groups. There's a sharp edges table that lists eight issues from critical to medium severity, though the actual problems aren't described in what I'm seeing. If you're adding Clerk to a Next.js 14 or 15 app, this gives you the core implementation patterns for sign in, sign up, route protection, and user session handling without hunting through docs.