Testing on Theseus: ownership, ordering, and the release gate

Testing on Theseus is the new starting point for testing a modular feature. It answers the questions teams ask most:

• Who owns end-to-end testing and release gating? Your team does, at every level. Release teams own the pipeline the tests run in.
• What should I test first? Contract tests against fakes, then end-to-end tests on Caproni for the few flows that span the stack, and monolith end-to-end tests only where your feature ties into the monolith.
• What is the release gate for? Protecting critical functionality. A failure there is a high-severity event, not how you find out your feature works.

The page links out to the handbook and the GitLab testing guides rather than duplicating them.