Pummelling the Platform–Performance Testing Shopify - Shopify

This post details Shopify's approach to performance testing for large sales events like BFCM. It introduces the concepts of load testing and stress testing, and explains the importance of generating realistic traffic shapes and hitting a variety of realistic endpoints. The post describes the internal load generation tool using Go and Lua (go-lua), and the development of Hardy Har Har (HHH) for HAR-based load testing to simulate real browser sessions at scale. It also highlights the use of ChatOps ('Spy') for test execution and reporting. The core contribution is the detailed explanation of the methodology and tooling used to ensure platform resilience under extreme load.