Every startup engineering conversation eventually arrives at: "But what if we need to scale?" Here's the uncomfortable truth: you probably won't. Not in the way Twitter or Uber scaled. The infrastructure decisions that make sense for 100 million users are actively harmful at 1,000. I inherited a project recently where the team was running a Kubernetes cluster and paying thousands a month in infrastructure costs. I moved it to Lambda + SQS and AWS App Runner and achieved the same result for...