Safely evolving database schemas in production systems
Database migration strategies cover the patterns and tools for modifying production database schemas without downtime. This includes migration frameworks (Prisma Migrate, Flyway, Alembic), zero-downtime patterns (expand-contract), data backfills, and rollback strategies. Schema changes are among the riskiest operations in production systems. Understanding how to make them safe, reversible, and non-blocking is essential for any backend developer working on evolving applications.