Watchgoose

Watchgoose is a hosted heartbeat monitor for scheduled work such as cron jobs, backups, queues and scripts. You create a check in the dashboard with its expected schedule, then have the job send an HTTP request to a unique ping URL, or email a check address, once it finishes successfully. When the next success signal is still missing after the scheduled time plus a grace period, the check goes down and alerts fire. A job can also signal failure itself.

Nothing needs to be installed: any job that can call a URL can be monitored. Schedules can be an interval, a weekly time, a cron expression or an on-calendar value, and implementation guides cover cron, systemd timers and GitHub Actions. Alerts go to configured channels including email, Slack, SMS, PagerDuty and webhooks, and the site mentions more than a dozen alert channels, a public status page and hosting operated in Europe. New accounts get 10 free checks with no card required.