The change was small, the diff looked sensible, and the existing tests passed.
Then I tried an empty list.
The original function returned []. The revised version returned None. Nothing immediately crashed, but code expecting a list had quietly received a different contract.
That gap is why I built Cross‑Examine.
Cross‑Examine is a verification harness for Python changes. Given a base Git revision and a proposed revision, it captures observed behavior from the base, then replays the same inputs against the changed code.
