Deployment Rollback Skill

Quick Rollback via Vercel

Using Vercel Dashboard

1. Go to Vercel Dashboard → Project → Deployments
2. Find the previous working deployment
3. Click the three dots menu → "Promote to Production"

Using Vercel CLI

# List recent deployments
vercel list

# Promote a specific deployment to production
vercel promote <deployment-url>

# Or rollback to previous production deployment
vercel rollback

Database Rollback

# Rollback last migration
pnpm -F @sgcarstrends/database db:rollback

# Rollback to specific migration
pnpm -F @sgcarstrends/database db:rollback --to 20240115_initial

# Restore from backup
pg_dump $DATABASE_URL > backup-pre-deploy.sql  # Before deploy
psql $DATABASE_URL < backup-pre-deploy.sql     # Restore if needed

Git-Based Rollback

# Revert specific commit
git revert <commit-hash>
git push origin main  # Triggers Vercel redeploy

# Create rollback branch
git checkout -b rollback/v1.1.0
git reset --hard v1.1.0
git push origin rollback/v1.1.0
gh pr create --title "Rollback to v1.1.0" --body "Emergency rollback"

Cache Invalidation

# Revalidate Next.js cache
curl -X POST "https://sgcarstrends.com/api/revalidate?tag=all&secret=$REVALIDATE_TOKEN"

# Clear Redis cache
redis-cli -h $REDIS_HOST FLUSHALL

Health Checks During Rollback

curl -f https://sgcarstrends.com || echo "Web unhealthy"
psql $DATABASE_URL -c "SELECT 1" || echo "Database unreachable"

Rollback Checklist

Pre-Rollback:

• Identify issue and severity
• Determine scope (full/partial)
• Check backup availability
• Notify team

During:

• Rollback via Vercel dashboard or CLI
• Rollback database if needed
• Clear caches
• Verify health checks
• Run smoke tests

Post:

• Monitor error rates in Vercel dashboard
• Verify functionality restored
• Document what happened
• Create postmortem

Common Scenarios

Critical Bug:

vercel rollback
curl https://sgcarstrends.com/api/health

Database Migration Failure:

pnpm -F @sgcarstrends/database db:rollback
git revert HEAD
git push origin main

Troubleshooting

Rollback deployment not working:

# Force redeploy from known good commit
git checkout v1.1.0
vercel --prod

Database schema mismatch:

pnpm -F @sgcarstrends/database db:rollback
# Or restore backup: psql $DATABASE_URL < backup-pre-deploy.sql

Best Practices

1. Always Backup: Create database backups before major deployments
2. Test Rollback: Practice rollback procedures in preview deployments
3. Feature Flags: Use for quick feature disabling without rollback
4. Monitor Closely: Watch Vercel analytics during and after rollback
5. Document Everything: Record what happened and why

References

• Vercel Rollbacks: https://vercel.com/docs/deployments/rollbacks
• See monitoring skill for debugging issues