If you’re working on an old code base that has had no style listing rules in place, received wisdom is that you start by running rubocop --auto-gen-config and revelling in the fact that subsequent runs of rubocop will run green. After years of following that advice myself, I’ve come to believe it’s wrong. The first step in my path to a better relationship between RuboCop and legacy code is now online: https://medium.com/@scottm/rubocop-in-legacy-projects-part-1-todos-and-todonts-877ace9f23b7