Is your migration safe or not safe?
This small Postgres migration checker flags common risky DDL before it reaches production. It uses a deterministic rule engine and PostgreSQL’s libpg_query parser compiled to WebAssembly; the browser version runs locally in a worker with no upload, login, or telemetry, and the project also exposes an npx CLI.
Treat it as an early warning, not a proof that a migration is safe: database state, table size, traffic, locks, and application-version overlap can change the real risk. HN commenters liked the local-first approach and suggested CI integration, but stressed those limits. One commenter showed a common false positive around adding a NOT NULL column without a default, while others recommended testing against a replica or reasoning about actual lock behavior.