[TazeTSchnitzel]

For audio software like this, using a GC-free language translates into reliable, stutter-free, low-latency playback, particularly on lower-power devices. A lot of JavaScript-based audio things I've tried, even really simple ones, become miserable experiences once GC pauses start consuming a lot of CPU. I think it's no surprise that GC'd languages are unpopular for audio applications!

[amelius]

But then you should also run it on a realtime OS.

[TazeTSchnitzel]

No, why would you? Normal OSes are pretty good at doing reliable audio playback and recording, musicians wouldn't use them otherwise. They don't guarantee five-nines but who cares. They are unlikely to ruin your audio experience.