I think you may be confused with a couple things. Devise and AuthLogic are both authentication gems, and wouldn't be used together. They only authenticate a us

I think you may be confused with a couple things. Devise and AuthLogic are both authentication gems, and wouldn't be used together. They only authenticate a user, but they don't authorize actions. For authorization, a gem like CanCan would be a good fit. saasramp looks like a way to do handle CC's and submit for processing. From my experience, don't do this. Let Chargify or someone else handle payments on a hosted payment page. It's not worth the risk.