In the last 6 months, I've helped 3 AI startups migrate from Vercel or Cloudflare to AWS Lambda. The pattern is the same: they start on a platform with great DX. Then the wall shows up: background jobs, retries, queues, cron, and eventually a "this endpoint needs 2-8 GB RAM for 4-10 minutes" workload — and they land on AWS.

To be fair: Vercel and...