EDIT: Updated for GitLab 6.2!
Rubinius is a high performance Ruby implementation. Recently the Rubinius team released the 2.0 version. A lot of effort has been put in it, especially in the past year. It’s got very mature and plays very nice with Rails.
GitLab is an “open source software to collaborate on code”, written using Rails 3 and lots of other awesome tools from the Ruby world.
Running GitLab is a good way to show off the capabilities of Rubinius 2.x when combined with a Web server that takes advantage of native threads and no global interpreter lock. In this case we’re going to use Puma.