Prompt regression testing in CI: a 5-minute setup

Your code has tests. Your code has a CI pipeline. A bad change can't merge without going green. Your prompts? Vibes. A teammate edits the system prompt to fix one customer complaint, output quality drops 8% on the other 99% of cases, nobody notices for a month, and the regression eventually surfaces as a mysterious churn bump in the metrics deck. This post is the 5-minute setup that closes that gap. What "tests for prompts" actually means There are two viable approaches and you need to know whic