Canard is now ORM agnostic.
David Butler has just added Mongoid support to Canard. Canard is yet another authorization rubygem. What sets Canard apart from the crowd is it builds on Ryan Bates' battle tested CanCan, wraps it up with Martin Rehfeld's RoleModel and makes authorization a first class citizen in your Rails app. Canard is now ORM agnostic and will work just as well in your non Rails apps.