Scaling Slack and GitHub with Maude Lemaire

About this episode

Brought to You By: • Antithesis – verify your system’s correctness without human review or traditional integration tests – and avoid bugs or outages. • turbopuffer – a vector and full-text search engine built on object storage. It’s fast, cheap, and extremely scalable. • Entire – The Git forge for agent-human collaboration. Built for the scale and throughput of agentic coding. — What is involved in scaling up large, popular products at places like Slack and GitHub?  We get an insider’s view on this from Maude Lemaire, a principal engineer and author of ‘Refactoring at Scale: Regaining Control of Your Codebase.’ She spent nearly eight years at Slack, where she led the backend performance infrastructure team, before joining GitHub to tackle database scaling challenges. Most recently, she worked on improving performance at Cursor – including time to first token. In this episode of The Pragmatic Engineer, Maude and I dig into the challenges of scaling some of the world's largest software products. We explore how Slack handled growing numbers of enterprise customers, how it evolved its approach to load testing, and the lessons Maude learned during nearly eight years of scaling Sl