A comprehensive reference for Ecto database patterns in Phoenix apps. Covers the full stack: schemas with proper changeset validation paired with database constraints, safe migration practices including DDL lock management, transactional workflows with Ecto.Multi, and performance concerns like N+1 preloading. The multi-tenancy section alone (prefix-based vs row-based partitioning) is worth having on hand. Particularly strong on the "don't just validate in changesets, enforce it in the database" principle that trips up developers coming from ORMs in other languages. If you're building anything beyond a toy Phoenix app, you'll reference the transaction and constraint patterns regularly.
npx skills add https://github.com/bobmatnyc/claude-mpm-skills --skill ecto-patterns