Most uptime tools ping a public URL. Gonewatch does the opposite: your job pings us. I built it after a nightly database backup failed silently — the script never started, so it never emailed me.
You create a monitor, paste a curl (or uses: gonewatch/heartbeat@v1) at the end of a successful run. If the next heartbeat never arrives, you get a Down email. Paid plans can post to Slack and remind you if it stays Down.
