This is great, and does not only apply to Rails. In many other frameworks it's common to lump business logic in controllers instead of models. Either way you

This is great, and does not only apply to Rails. In many other frameworks it's common to lump business logic in controllers instead of models. Either way you end up with the same thing: eventually you'll need to add a 4th (at least) type on to MVC. > Here at Grouper, we’re long-time users of Ruby on Rails – along with other New York startups like RapGenius, Etsy and Kickstarter. Etsy doesn't use Rails though, it uses PHP.