On August 22, 2016, Buildkite experienced a severe outage due to a series of technical and operational mishaps, including misconfigured PagerDuty settings, database performance issues following a rushed AWS infrastructure downgrade, and AWS IAM issues. The outage was compounded by a failure in health checks and replacement server deployments, which were based on outdated AMIs, leading to a cycle of server failures. The team acknowledged their oversight in not conducting proper load testing and monitoring of AWS credits, resulting in hasty decisions that impacted service availability. Despite the challenges, Buildkite expressed gratitude for customer understanding and committed to learning from the incident to prevent future occurrences, emphasizing the importance of improved technical strategies and team coordination.