I don't know how the challenges with cooperative (no-preemptive) multitasking keep needing to get rediscovered. Even golang, which I consider a very responsibly designed language, went with cooperative at first until they were forced to switch to preemptive. Not saying cooperative multitasking doesn't have its place, just that it's gotta have a warning sticker or even better disallow certain types of code from executing statically.

Also great time to plug a related post, What color is your function:

https://journal.stuffwithstuff.com/2015/02/01/what-color-is-...