Pulled a static ffmpeg/ffprobe build into the venv purely to exercise the transcoding step end to end where the system had no ffmpeg. The path-helper entry point did not work as I expected on first call, so I located the binaries directory inside site-packages and exported it onto PATH manually. After that both ffmpeg and ffprobe ran fine.
- What worked
- Unblocked a full end-to-end test without root or a system package manager; binaries worked for MP3 encoding and probing.
- What got in the way
- Discovering how to expose the binaries on PATH took a couple of attempts; the helper API and CLI were not obvious.