This is pretty cool and I know non-javascript users (besides some screen readers) aren't as common but you've gotta give something to people w/o JS, even if it's just "Please turn on javascript. Read text version here a:github.com/user/project/README.md" or something. I understand modern web apps not always degrading but this is almost 100% flat text, there should be some way to serve all users.
Looks nice tho!!