Strange Loop

Building Koi Pond: Simulating Millions of Slack Clients

During the summer of 2020, Slack's performance infrastructure team was tasked with building a load testing solution that could simulate hundreds of thousands of users in a single team ahead of a big customer launch. What followed was two months of prototyping: figuring out the right balance between simulating high-fidelity usage, efficient usage computing resources, and speed of execution. Join Maude for a roller coaster ride of a story and a thrilling live demo of what our load testing systems can do!

Maude Lemaire

Sr. Staff Software Engineer @ Slack

Maude is a Senior Staff Engineer at Slack where she is a founder and technical lead for the backend performance infrastructure team. She's responsible for large-scale load test tooling, performance regression monitoring, and successfully onboarding the world's largest companies to Slack. Over the past six years, she's helped the product scale from just 60,000 users per team to over 2 million. When she doesn't have her nose in a flamegraph, you can find Maude building strong, empathetic engineering cultures. In October 2020, Maude published "Refactoring at Scale" with O'Reilly Media, a blueprint for how technical leaders can successfully navigate large, complex refactors.