The same dead-man's-switch idea — your job checks in, and silence triggers an alert — with a generous free tier.
A "dead man's switch" monitors the absence of a signal: your job pings on every run, and if a ping never arrives within the grace window, you're alerted. That's the only reliable way to catch a job that didn't run at all.
/start to catch hung jobs and measure duration; /fail and exit codes for explicit failures.Ready to wire this up? Create a free check — 20 checks, all alert channels, no card.