It is served from github using the "pages" functionality. According to an article from 2009 they are using nginx to serve. https://github.com/blog/530-how-we-m

It is served from github using the "pages" functionality. According to an article from 2009 they are using nginx to serve. https://github.com/blog/530-how-we-made-github-fast https://github.com/blog/530-how-we-made-github-fast