Yeah, this is cool and similar to the end state I have in mind. The main difference is that I am not trying to create the curriculum/exercises. I am just creating flaschards that say "Solve exercise x.y.z in that textbook". Plus the whole free-software angle and being able to share the material as text files.
The math thing is just a side project at the moment to try to see how it works for other fields. I am primarily using this for music. I was hoping something like this existed already, but all the solutions are either very specialized like this one or do not support dependencies as a core feature, like Anki. Had Anki supported something like this, I wouldn't have needed to make my own thing.