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name: clerk-auth description: "Expert patterns for Clerk auth implementation, middleware, organizations, webhooks, and user sync Use when: adding authentication, clerk auth, user authentication, sign in, sign up." source: vibeship-spawner-skills (Apache 2.0)

Clerk Authentication

Patterns

Next.js App Router Setup

Complete Clerk setup for Next.js 14/15 App Router.

Includes ClerkProvider, environment variables, and basic sign-in/sign-up components.

Key components:

• ClerkProvider: Wraps app for auth context
• <SignIn />, <SignUp />: Pre-built auth forms
• <UserButton />: User menu with session management

Middleware Route Protection

Protect routes using clerkMiddleware and createRouteMatcher.

Best practices:

• Single middleware.ts file at project root
• Use createRouteMatcher for route groups
• auth.protect() for explicit protection
• Centralize all auth logic in middleware

Server Component Authentication

Access auth state in Server Components using auth() and currentUser().

Key functions:

• auth(): Returns userId, sessionId, orgId, claims
• currentUser(): Returns full User object
• Both require clerkMiddleware to be configured

⚠️ Sharp Edges

Issue	Severity	Solution
Issue	critical	See docs
Issue	high	See docs
Issue	high	See docs
Issue	high	See docs
Issue	medium	See docs
Issue	medium	See docs
Issue	medium	See docs
Issue	medium	See docs