From the Bookshelf of Ruby on Rails Reading…

[close] Many people talk about the speed of Rails applications and how that dramatically slows down over the life of the application. They mention slow test suites due to loading the entire Rails environment.

This book talks about how to think differently with our Rails code. Instead of thinking everything needs embedded in a model, view, or controller, he shows specific examples of how to extract pieces of responsibility and then integrate them into the Rails application.

I believe this helps to drive toward a better design - and also giving the needed boost in speed.