System Resilience Engineering: From Reactive Firefighting to Proactive Defense
Overview 2 AM. Your phone buzzes. The payment service is timing out, thread pools are exhausted, upstream order services are queuing up, and ten minutes later the entire transaction pipeline collapses. You check the logs: a downstream cache cluster hiccuped for 3 seconds. During those 3 seconds, upstream services retried frantically, maxing out connection limits, and everything sharing that connection pool went down together. This story isn’t new. Almost anyone who’s done operations for a few years has lived through a similar cascading failure....