Topic
Techniques for isolating defects, such as hypothesis elimination and runtime monkey-patching for observation.
Pion v4 moved RTCP writing onto the PeerConnection, so a Go SFU now has to rewrite the MediaSSRC on every PLI, FIR and NACK it forwards. Skip that step and RTCP keeps flowing while the keyframe never arrives.
Reality
A queue worker built its remaining-seconds budget from time.time(), and after the host woke from sleep it logged remaining=-1842.7. Two days of debugging went to sockets, Docker and NTP before the clocks got compared.
Reality
A dev.to write-up traces two nights of hex dumps to a shell that exported PYTHONUTF8=1 on the laptop and nothing on the clean Linux box, where open() fell back to the POSIX locale's ASCII codec.
Reality
A voice avatar kept its microphone button lit while the server logged 0.00 volume, and the fix needed three failed hypotheses before a log showed the widget enabling a track that was about to be discarded.
Reality
Two hours of debugging a git-push-to-deploy hook ended with set -x printing docker stop APP_NAME, the literal word. The writeup calls the cause inconsistent quoting; its own trace shows there was no expansion to quote.
Reality
Two runtime-equivalent calls, one no-member error. The cause sits in astroid's implicit __call__ path, where a failed attribute lookup kills the generator before the correct branch runs.
Reality