# 31. Backup Strategy & Point-in-Time Recovery

meta:
  id: web-production-31
  feature: web-production
  priority: P1
  depends_on: []
  tags: [database, reliability, production]

objective:
- Implement automated database backups with point-in-time recovery capability

deliverables:
- Automated daily backups
- Point-in-time recovery setup
- Backup testing and verification
- Retention policy

steps:
1. Set up automated backups:
   - If PostgreSQL: configure pg_dump cron job or managed backups (RDS, Cloud SQL)
   - If SQLite/Turso: configure Turso database branching/backups
   - Daily full backups at off-peak hours (3 AM UTC)
   - Hourly incremental backups (WAL archiving for Postgres)
2. Configure backup storage:
   - Store in separate region/cloud provider (S3, GCS, R2)
   - Encrypt backups at rest
   - Versioning enabled (protect against deletion)
3. Implement point-in-time recovery:
   - WAL archiving for PostgreSQL
   - Transaction log backups every 15 minutes
   - Test recovery to specific timestamp
4. Add backup monitoring:
   - Alert on backup failure
   - Track backup size and duration
   - Verify backup integrity (checksum)
5. Test restore procedures:
   - Monthly restore test to staging environment
   - Document step-by-step restore process
   - Measure RTO (Recovery Time Objective) and RPO (Recovery Point Objective)
   - Target: RTO < 1 hour, RPO < 15 minutes
6. Document retention:
   - Daily backups: 7 days
   - Weekly backups: 4 weeks
   - Monthly backups: 12 months
   - Annual backups: 7 years (compliance)
7. Add Redis backup:
   - RDB snapshots every 6 hours
   - AOF persistence for point-in-time
   - Backup to S3/GCS

tests:
- Integration: Test backup creation
- Recovery: Test restore to staging
- Monitoring: Verify backup alerts

acceptance_criteria:
- Daily automated backups running successfully
- Backups stored in separate region with encryption
- Point-in-time recovery tested and working
- Backup failures trigger alerts within 5 minutes
- Monthly restore test completed and documented
- RTO < 1 hour, RPO < 15 minutes
- Retention policy enforced automatically
- Redis backups included in strategy

validation:
- Check backup storage → daily backups present
- Trigger restore test → staging database restored successfully
- Simulate backup failure → alert received
- Check retention → old backups purged per policy

notes:
- Turso offers automatic backups for SQLite — verify configuration
- RDS automated backups are easiest for PostgreSQL
- Test restores are critical — untested backups are useless
- Document restore process for on-call engineers