Stripe recently began generating API libraries in seven different programming languages, after maintaining them by hand for eight years. We wanted the generated code to offer just as good a user experience and be no less readable than the handcrafted code, while keeping breaking changes to a minimum, so we built a tool for this ourselves: a compiler of sorts. This talk is a deep dive into how we built our tool and lessons we learned along the way. Richard Marmorstein Stripe @twitchard Richard Marmorstein is an autonomous, general-purpose problem solving and entertainment system, implemented chiefly in deoxyribonucleic acid, that exposes a rich natural language interface. He presently resides in New York and works as a software engineer on the API Experience team at Stripe. When he is not API Experiencing, he is hanging out with his two dogs, Mozzarella and Gouda. Recorded at Strange Loop 2021 https://thestrangeloop.com