The Day Our Serverless Dream Turned into a Nightmare

It was 3 PM on a Tuesday. Our “serverless” order processing system — built on AWS Lambda and API Gateway — was humming along, handling 1,000 transactions/minute. Then, disaster struck. A sudden spike in traffic caused Lambda timeouts, API Gateway threw 5xx errors, and customers started tweeting, “Why can’t I check out?!”

The post-mortem revealed the harsh truth: we’d never tested failure scenarios. Our “resilient” serverless setup had no fallbacks, retries, or plans for chaos.