It's open source, and we wrote some technical documentation at https://github.com/code-dot-org/code-dot-org/blob/600ebafa52....

There were a bunch of interesting aspects to this project. One of my favorite things was developing the user programming model. Organizing your music using functions is very powerful.

http://reference.wolfram.com/language/guide/SoundAndSonifica...

https://news.ycombinator.com/item?id=10180423

In the comments, I saw reference to MML ( Music Macro Language ... not exactly what I think the MML is on the list. ) Here's the one referenced in the HN post.

https://en.wikipedia.org/wiki/Music_Macro_Language

At the time, I built a small interpreter that included MML as an embedded language, but I don't think I have the (Windows) binaries handy.

I learned about it after stumbling across the creator's short, fun videos showing it being used: https://youtube.com/playlist?list=PL_yUKG0GRuliL65l_qEG1uwCC... ("Python Music Shorts")

https://alda.io/

  Delay delay;
  LPF filter;
  Reverb reverb;
  Gain feedback;
  
  adc => delay => filter => reverb => dac;
  filter => feedback => delay;