Clerk Upgrade & Migration Skill

Clerk Upgrade & Migration

Current State

!npm list @clerk/nextjs @clerk/clerk-react @clerk/express 2>/dev/null | grep clerk || echo 'No Clerk packages found'

Overview

Safely upgrade Clerk SDK versions and handle breaking changes. Covers version checking, upgrade procedures, common migration patterns, and rollback planning.

Prerequisites

Current Clerk integration working
Git repository with clean working state
Test environment available for validation

Instructions

Step 1: Check Current Version and Available Updates

# Check installed version
npm list @clerk/nextjs

# Check latest available
npm view @clerk/nextjs version

# Check all Clerk packages and their versions
npm outdated | grep clerk

Step 2: Review Breaking Changes

# View changelog for the target version
npx open-cli https://clerk.com/changelog

# Check GitHub releases for migration notes
npx open-cli https://github.com/clerk/javascript/releases

Key version milestones to watch for:

v5 to v6: auth() became async (must await auth())
v5 to v6: authMiddleware renamed to clerkMiddleware
v5 to v6: Import paths changed to @clerk/nextjs/server

Step 3: Upgrade Process

# Create upgrade branch
git checkout -b chore/upgrade-clerk

# Upgrade all Clerk packages together (they must version-match)
npm install @clerk/nextjs@latest @clerk/themes@latest

# If using other Clerk packages:
# npm install @clerk/clerk-react@latest @clerk/express@latest @clerk/backend@latest

# Verify no version mismatches
npm list | grep clerk

Step 4: Handle Common Migration Patterns

v5 to v6: auth() is now async

// BEFORE (v5): auth() was synchronous
// const { userId } = auth()

// AFTER (v6): auth() returns a Promise
const { userId } = await auth()

Find all affected files:

# Search for synchronous auth() calls that need await
grep -rn "const.*= auth()" --include="*.ts" --include="*.tsx" | grep -v "await"

v5 to v6: Middleware migration

// BEFORE (v5):
// import { authMiddleware } from '@clerk/nextjs'
// export default authMiddleware({ publicRoutes: ['/'] })

// AFTER (v6):
import { clerkMiddleware, createRouteMatcher } from '@clerk/nextjs/server'

const isPublicRoute = createRouteMatcher(['/'])

export default clerkMiddleware(async (auth, req) => {
  if (!isPublicRoute(req)) {
    await auth.protect()
  }
})

v5 to v6: Import path changes

// BEFORE:
// import { auth, currentUser } from '@clerk/nextjs'

// AFTER:
import { auth, currentUser } from '@clerk/nextjs/server'

Fix import paths across codebase:

# Find files using old import path
grep -rn "from '@clerk/nextjs'" --include="*.ts" --include="*.tsx" | grep -v "node_modules" | grep -v "/server"

Step 5: Update Type Definitions

// If using custom type extensions, update them
// BEFORE:
// declare module '@clerk/nextjs' { ... }

// AFTER:
declare module '@clerk/nextjs/server' {
  interface AuthObject {
    // Custom session claims type
    sessionClaims?: {
      metadata?: {
        role?: string
      }
    }
  }
}

Step 6: Test Upgrade

# Build to catch type errors
npm run build

# Run tests
npm test

# Start dev server and test manually
npm run dev

# Test critical flows:
# 1. Sign in with email/password
# 2. Sign in with OAuth
# 3. Protected route access
# 4. API route authentication
# 5. Webhook endpoint
# 6. Sign out

Step 7: Rollback Plan

# If upgrade fails, rollback to previous version
git stash  # Save any manual changes

# Install previous version
npm install @clerk/nextjs@5.x.x  # Replace with your previous version

# Or restore from git
git checkout main -- package.json package-lock.json
npm install

# Verify rollback works
npm run build && npm test

Output

Clerk SDK upgraded to latest version
Breaking changes migrated (async auth, new middleware, import paths)
Type definitions updated
All tests passing
Rollback procedure documented

Error Handling

| Error | Cause | Solution | |-------|-------|----------| | Type errors after upgrade | API signature changes | Add await to auth(), update imports | | authMiddleware is not exported | Renamed in v6 | Use clerkMiddleware from @clerk/nextjs/server | | auth() returns Promise | Now async in v6 | Add await to all auth() calls | | Import not found | Path changed | Use @clerk/nextjs/server for server-side imports | | Version mismatch | Clerk packages on different versions | Update all @clerk/* packages together |

Examples

Automated Migration Script

#!/bin/bash
# scripts/migrate-clerk-v6.sh
set -euo pipefail

echo "=== Clerk v5 to v6 Migration ==="

# 1. Fix auth() calls (add await)
echo "Adding await to auth() calls..."
find . -name "*.ts" -o -name "*.tsx" | xargs grep -l "const.*= auth()" 2>/dev/null | while read file; do
  sed -i 's/const \(.*\) = auth()/const \1 = await auth()/g' "$file"
  echo "  Fixed: $file"
done

# 2. Fix import paths
echo "Updating import paths..."
find . -name "*.ts" -o -name "*.tsx" | xargs grep -l "from '@clerk/nextjs'" 2>/dev/null | while read file; do
  if grep -q "auth\|currentUser\|clerkClient" "$file"; then
    sed -i "s/from '@clerk\/nextjs'/from '@clerk\/nextjs\/server'/g" "$file"
    echo "  Fixed: $file"
  fi
done

echo "Done. Run 'npm run build' to check for remaining issues."

Resources

Next Steps

After upgrade, review clerk-ci-integration for CI/CD updates.

Agent Skills: Clerk Upgrade & Migration

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