If I had to pick one engineering team to write up how they make (and keep) Rails running fast, it’d be Shopify’s. What a treat! Part of Shopify’s success with Ruby on Rails is an emphasis on writing fast code. But, how do you really write fast code? Largely, that’s context sensitive to the problem you’re trying to solve. Let’s talk about a few ways to start writing faster code in Active Record, Rails, and Ruby.