Resiliency Planning for High-Traffic Events - Shopify

This post details the evolution of Shopify's resiliency planning for high-traffic events. It elaborates on the use of load and stress testing to identify system limits and regressions, and introduces the concept of a user-centric resiliency matrix to document failure modes and their impact on user experience. The post also emphasizes the importance of 'game days' to test the documented model against reality and adjust in a controlled setting, exercising technical, human, and organizational defenses. It highlights the need to avoid single root cause attribution in incident analysis and to address deeper systemic issues. For BFCM specifically, the post notes a slowdown in the rate of change, with increased focus on performance, reliability, and scale, including more frequent load tests and game days.