Canary Deployment

1. The Incident

Version 1.43 follows the last lesson's process. Green passes health checks, production smoke tests, and warmup before the traffic switch at 14:00. The deployment system reports success because every environmental check passes. Connections open normally, caches are warm, and the new instances serve their synthetic requests within the expected latency range.

At 14:08, support reports that checkout fails for users with a saved payment method and a non-US locale