For fun (and because ilearn sucks), I taught a computer science class where the students helped create a learning management system based on git. Each student's grades are stored in a repo that they own, and the instructors use signed commits to update the students' grades. I offered an extra credit bounty to anyone who could write arbitrary grades to their repo without getting caught, and had a few students discover some clever loopholes.

The documentation is super unpolished, but you can find the repos here: https://github.com/mikeizbicki/gitlearn

The "how grades are stored" file in the docs is probably the most interesting: https://github.com/mikeizbicki/gitlearn/blob/master/docs/gra..., but there's also docs on how to start up and run a class using gitlearn.