Improving the design of existing software is a creative and imaginative process. In order to discover creative refactoring solutions, it's important to be able to quickly try out new design ideas. But it can be hard to do this kind of playful prototyping when we're limited by dependencies, broken configurations, or slow builds. In today's episode, guest chef Nick Sutterer shows us how he approaches refactoring and redesign in Rails applications. By using some clever tricks to temporarily exclude database dependencies, he's able stay focused on the domain model as he plays with new approaches. It's a novel and productive technique, and I hope it inspires you. Enjoy!