Is this tutorial interface (navigation, diffs, files/downloads at each step) custom made? It's pretty nice for this kind of format.
It was custom made for the tutorial. I didn't release it yet because I mostly focused on polishing the tutorial itself and not the code for the interface. Do you think people would be interested in the interface by itself?
Yes, 100%.
The tutorial on git is super cool, but for me the thought of constructing my own tutorials using a framework that got you here is even cooler.