Hello. I write open source CMS (Constructor) on Rails 4. Version of project is 0.7.3 now. I wanted to tell about it when version 1.0.0 will be released but I can’t wait )).
RoR developers, please look http://github.com/ivanzotov/constructor. This CMS has interesting template system, that allow you to build complex web sites.
For example avgust-klimat.ru – site built on constructor.