Found another one:
https://www.cs.columbia.edu/~sedwards/classes/2021/4115-fall...
https://github.com/kkysen/cstar
And to sibling comments: I care. Non-mainstream languages are talking points. I don't want to get 15 minutes into a "you should have effects like Koka" argument and then find out the other person is talking about a different Koka.