What problem does it solve? Schema changes in Spring Boot projects often drift from the migration history, break on deployment, or fail silently when wiring is wrong. This Skill enforces a disciplined, forward-only migration workflow so every relational schema change is versioned, reviewed, and reproducible in every environment. ## Core Features & Use Cases - Tool decision and wiring: Reads the recorded Flyway or Liquibase choice from the project profile, asks the user when nothing is recorded, and enforces the Spring Boot 4 starter requirement that prevents migrations from silently never running. - Immutable, ordered history: Enforces never editing applied migrations, resolving branch version conflicts by renumbering the later branch, and one migration per logical change. - Expand-and-contract for breaking changes: Splits renames, type narrowing, NOT NULL additions, and drops into expand, migrate, and contract phases, with separate batched, resumable backfills and business-keyed seed data. - Use Case: A developer adds a status column to a populated users table. The Skill guides them to add it nullable (expand), backfill in a separate batched migration (migrate), and add the NOT NULL constraint in a later release (contract), then verify with a clean install from an empty database. ## Quick Start Ask the assistant to write a Flyway migration that adds a new table with named constraints and indexes, then verify it with a clean run from an empty database.
