Git for Postgres data, built for agents. Give an agent its own branch of your real database, as nothing more than a connection string. See every field it changed, merge it into main when it's right, and undo it if it wasn't.
Gnomon runs inside the Postgres you already have. One extension, no copies, no second database.
A branch reads everything from main and keeps only what it changes, so it opens instantly and copies nothing, however big your database is. Give one to every agent run, every pull request and every test.
Your application doesn't change. A branch is a connection string: point a session at it, and the queries it already runs read and write the branch instead of main.
