Migration Safety

CRITICAL: Migrations can destroy production data. This skill prevents catastrophic data loss.

The Problem This Solves

Real disaster scenarios:

• Migration fails halfway, rollback deletes all records
• Re-running migration truncates existing data
• Column drop removes 50,000 user records
• Foreign key constraint fails, cascade deletes everything
• "Fresh migration" on wrong database wipes production

Golden Rules

1. NEVER run migrations without checking for existing data first
2. ALWAYS create a backup before ANY migration
3. NEVER re-run a migration that previously partially completed without investigation
4. ALWAYS verify you're on the correct database/environment