How to Test Email Signup Flows in CI/CD Pipelines

The Pain Every CI Pipeline Knows It works locally. The signup form submits, the confirmation email arrives in your inbox, you paste the OTP, it verifies. Ship it. Then CI runs. The test sends the signup request, polls... and times out. Or worse: it passes because you mocked the email sender and never actually tested that the email arrives, renders correctly, or contains a working code. Email signup flows break in CI for a handful of predictable reasons: Shared inboxes — two parallel test runs bo