signalapp/signal-android: technical due diligence, read from its repository

Of 1214 fixes in the last 24 months, 225 touched a test. A fix without the test that would have caught the bug can quietly come back, and the suite never learns from what went wrong.

Matches for Google API key appear in tracked files outside test and fixture paths. They stay in the history even after they leave the tree, so what matters is whether each was rotated. The code cannot tell whether any of them is live, and that decides whether this matters: none sits in production configuration, and none is in a format its provider keeps for live keys. Is any of these live? Show that each was rotated after it was committed, and when. Only Google API keys matched. Those are often public by design, in a browser app's Firebase or Maps configuration; the question is whether each is restricted to the app's domains and APIs.

There is no disclosure policy, no automated dependency updates, no named code owners and no pre-commit configuration. None of these is load-bearing on its own. Their collective absence says that security posture here is whatever the current team happens to remember to do, which is not a posture that survives the team changing.

No USER instruction switches away from root, so the process runs with full privileges inside the container. It is a one-line fix and an ordinary expectation, which is why its absence is worth asking about: it usually says more about whether anyone has reviewed the deployment than about this container specifically.