Everyone knows the rule “fat models, thin controllers”. It’s really efficient when it comes to simple applications, but when we have an enterprise application, suddenly our models seem to look a bit overweight. Actually they are fat and ugly. I want to show a few examples of using DCI architectural pattern (which is complementary to MVC pattern) with Rails as a potential solution for these problems. My personal goal is to encourage people to experiment with the code and thinking outside the box (Rails box). Start thinking through domain model, not database design, to look at Datamapper pattern and DDD concepts. However, DCI is a good start to enter this enterprise world.