I have also been running into program memory issues. You can take a look at my post here:
From my findings, it appears the base code takes around 91% of program memory ever with a blank project (on a V1.x micro:bit). I’ve been looking for ways to reduce memory size while maintaining core functionality for students using it.
Maybe let me know if you’ve found anything and I’ll do the same.
I realize this is a very old thread, but I’m running into the same problem. I was attempting to make an OS for the Micro:bit V2 a while back, and eventually hit a memory limit.
I, as joshkeys mentioned, also realized that the music functions take up a ton of memory. But it’s just unfortunate that there isn’t a lot of memory