cron

Systemd Timers for Backups: Systemd offers a robust alternative to cron for scheduling tasks, solving issues like missed runs if the system is down. To create a backup timer, define .timer and .service files in /etc/systemd/system, specifying timer frequency with OnCalendar and whether the timer is persistent. Install and enable the timer with systemctl enable backup.timer. The service file includes the backup command and allows for executing pre/post commands for notifications on the backup status. Use systemctl commands to manage and check the status of timers and services.

https://yieldcode.blog/post/working-with-systemd-timers/

FastCron: Reliable online cron job service for managing tasks across multiple sites. Offers free and paid plans, team collaboration, customizable options, automation, and notifications via email and other channels. Over 8,000 developers use it for various tasks. Start with a free account; upgrade options available.

https://www.fastcron.com/

Crontap schedules API calls using cron or human-readable syntax, integrating with thousands of apps via Zapier or Make. It offers features like timezone settings, header and payload management, instant testing, error tracking, and historical logs. Ideal for developers, Sysadmins, and business owners, it's useful for automated backups, maintenance, monitoring, payments, reminders, and more. Sign up for free, no credit card required.

https://crontap.com/

Free cron jobs, from minutely to yearly. Features: execute 60x/hour, versatile scheduling, execution history, custom HTTP requests, test runs, status notifications, multi-factor auth, REST API, eco-friendly, open source, funded by donations. Trusted by tens of thousands with millions executed daily.

https://cron-job.org/en/