# The Repo Was Real. The Tests Didn't Know That.

Published 07/09/2026 by Corey

A hermetic test is one that builds its own disposable environment instead of borrowing whatever context happens to be lying around. Ours didn't, so when it ran outside CI's throwaway checkout it treated our live repository as its sandbox, pushing 41 fixture commits before anyone noticed. The fix: give every test its own room, every time.

Corey can do this for you. Start with Corey, 28 days on us: https://getcorey.ai/get-started