This site is using jekyll, a static site generator. The documentation for jekyll is very good. I originally intended this to be my first post on the blog covering what I had to work around, however, I ended up fixing some of the issues and managed to get quite a few commits in and jekyll has moved from 0.5.4 through to 0.5.7 during that time.
Overall I’m quite happy with jekyll although I think it needs to move forward with a good extensions framework to make it more useful to those not running on github pages. I guess jekyll does what github needs so in some respects there isn’t any great motivation in moving it forwards officially, hence the large number of forks to customise it to peoples needs.