Back from a short hiatus, Pascal is joined by Jon to talk about the infrastructure that allows commit to sync between Meta's monorepo and GitHub. While ShipIt has been around for a while, allowing commits from the internal repository to sync out to GitHub, Diff Train is its younger brother to allow the inverse. This makes it possible for open-source-first projects like PyTorch to develop on GitHub and bring changes back into the monorepo without sacrificing security and reliability. Got feedback? Send it to us on Twitter (https://twitter.com/metatechpod), Instagram (https://instagram.com/metatechpod) and don’t forget to follow our host @passy (https://twitter.com/passy). Fancy working with us? Check out https://www.metacareers.com/. Links: https://github.com/facebook/pyre-check https://github.com/facebookincubator/cinder https://github.com/facebook/hhvm https://github.com/facebook/fbshipit Timestamps: Intro 0:06 Intro Jon 1:49 Open-sourcing an internal project 7:26 Open Source Team @ Meta 10:22 Third-party dependencies 12:07 ShipIt 13:48 Diff Train 29:01 Most excited about 41:07 The GIL 42:29 Outro 44:22