Release checklists often prove the API is up, the queue is draining, and the UI loads. Then an approval email ships with the wrong hostname, or a reset link points at yesterday's env. That gap is why I keep one small email check in the release path now. It is not fancy, but it saves a lot of avoidable thrash.
I am not talking about a giant suite. I mean one replayable workflow for the email that matters most in that release: signup, approval, password reset, invite, whatever is user-visible and easy to break. A fake email address is useful here as an isolated target, but the real win comes from how you structure the check around it.
Why release checks miss email regressions
Most teams already test email somewhere. The problem is that those tests are often too far away from the release itself. Unit tests prove templates render. Integration tests prove an event may enqueue. Manual QA proves somebody saw a message once. None of that fully answers the release question: did this deploy produce the right message, for the right flow, with the right destination, right now?
That sounds small, yet it catches very real bugs:
