Jeykll is a simple static site compiler. We're using it here to build a static site which can make use of basic templates.
When working on the project you can run the following command:
bundle exec rackup
This will start a web server on port 9292, so visit localhost:9292 and you should see the site. If you change the templates or code you should see the changes straight away.
Liquid templating docs
and Jekyll's liquid extensions https://github.com/mojombo/jekyll/wiki/liquid-extensions