Most ERD tools were built for DBAs. Schemity is built for software engineers. 9 MB, offline-first, Git-native. Your ERDs live as plain JSON in your repo, commit, diff, and review like code. Drag fields to create relationships. Flexible lines with custom waypoints. Check constraints as first-class citizens. Compare ERD to live DB and generate the exact SQL diff. Supports PostgreSQL, MySQL, SQL Server, Supabase. No Electron. No JVM. No subscription.