RailsConf 2025 Simplifying at Scale: 7 Years of Rails Architecture at Persona by Alex Coomans

What does it really take to scale a Ruby on Rails architecture to power a global identity platform trusted by businesses around the world? From our early days on Google App Engine to a globally distributed, multi-cluster Kubernetes deployment, this talk takes you through the evolution of Persona’s architecture. We’ll dive into the architectural turning points that shaped our journey: the trade-offs we faced, the mistakes we made, and the surprising ways complexity crept in. Most importantly, we’ll share why simplicity might be the key to scaling successfully without losing your mind. Whether you’re just starting out or wrangling scale yourself, you’ll leave with battle-tested insights on system design, technical decision-making, and building for the long haul that’ll help you build best-in-class Rails applications.