migration-helper

What problem does it solve?

Database and code migrations are often risky, leading to downtime, data loss, or application errors if not executed carefully. This Skill provides expert guidance and proven patterns for performing safe, incremental, and zero-downtime migrations, minimizing risk.

Core Features & Use Cases

• Migration Safety Rules: Enforces critical rules like backing up data, testing on staging, making changes reversible, and monitoring during execution.
• Database Migration Patterns: Offers strategies for schema changes (add/remove/rename columns, add index concurrently) and a detailed zero-downtime deployment pattern.
• Code Migration Strategies: Guides through techniques like feature flags and the Strangler Fig Pattern for safe code transitions.
• Use Case: When adding a new required column to a large production table, use this skill to follow the zero-downtime pattern: add nullable, dual-write, backfill, switch reads, remove old writes, then safely drop the old column.

Quick Start

Help me plan a zero-downtime database migration to add a new required column 'status' to the 'users' table