Imported from jeremylongshore/tons-of-skills-marketplace (skills/.curated/clerk-upgrade-migration/SKILL.md). Install upstream with npx skills add jeremylongshore/tons-of-skills-marketplace --skill clerk-upgrade-migration. Copyright stays with the author (MIT).

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npm outdated | grep clerk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

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

• Clerk Changelog
• Clerk Upgrade Guides
• GitHub Releases

Next Steps

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