Often we know that our code needs refactoring, but we have no idea where to start. Maybe we studied some common code smells and learned about the things that we should be avoiding, but memorizing the rules doesn’t automatically lead to fixing all problems. In this talk, we explore how you can use Git to recognize and address violations to each of the SOLID principles. Using diffs, commit history and pull requests you can learn to recognize patterns in code that point to problems. These same tools can help you correct those issues and write more maintainable code.