Rapid release at massive scale

What this post added

This post details the evolution of Meta's release engineering process from a branch/cherry-pick model with three daily pushes to a quasi-continuous "push from master" system for web, and the development of a comprehensive build and test stack for mobile. Key technical contributions include the transition to deploying directly from master for web, enabling tens to hundreds of diffs every few hours with tiered rollouts and the Gatekeeper system for risk mitigation. For mobile, it outlines a three-layered CI stack (builds, static analysis with Infer, and automated testing) that runs on every commit, leading to reduced release cycles from weeks to days. The post also highlights the elimination of hotfixes, better support for global engineering teams, and the development of next-generation tools and processes driven by the need for scale.