Cost Is a Distributed Systems Bug

The bill arrived on a Tuesday. One hundred and twenty thousand dollars in three days — enough to fund two junior engineers for a year, enough to lease a small datacenter rack, enough to make the VP of Engineering physically ill. The culprit? An autoscaling group that treated a DDoS attack like legitimate traffic, spinning up instances with the mindless enthusiasm of a Fibonacci sequence. No circuit breaker. No spend ceiling. Just pure, algorithmic faith that more capacity solves all problems. This is what happens when we treat cost as someone else's concern.