I started working on Nitro a long time ago. Browsing the source code I realized that over the years a lot of unused functionality has accumulated. Some core components of Nitro are more complex than they should be. In hindsight, I can implement many features more elegantly, efficient and user-friendly. And, in the process, make the code more readable.
It is very fortunate that these days I can devote some time to improve the code-base. If you fell adventurous enough, pull the latest changes from the repo version and have a look at my work in progress. And while you are at it, send your suggestions to the mailing list or even better do submit some cleanup patches. I can use all the help I can get.
PS: You can expect some great new features too: RESTful controllers, implicit support for Atom publishing, Sitemaps and more...