These are all in some degree in alpha quality, but I know Kotlin and Rust are working. I don’t remember what the status of Arduino is. There are some fun examples in there, including shipping over a stream of FFTs of outbound audio from my laptop.
I’m afraid brain cancer has removed my ability to write code beyond very simple stuff, and I haven’t been able to work on these for a while. If anyone is interested in taking over one or all of them, let’s talk 
Those are awesome. I could pick up the arduino one. Kotlin and rust aren’t languages I’ve picked up yet. I’ve done a lot of Java in the past though, and Rust is displacing C++ in embedded in many areas.
This looks great! I know Kotlin well and would be happy to pick up the Kotlin side of things if you’d like. It has been on my todo list to write something like this anyway, maybe now I don’t have to 
[edit: my github is https://github.com/chrismiller if that’s helpful]
Sounds great, thanks so much 