Build a .service for your program or script: user, working folder, environment, automatic restart, plus a .timer from a cron-style schedule, with install and check commands.
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Why systemd rather than cron
systemd restarts a crashed program, starts it after the network, keeps its output in the journal (journalctl -u name) and runs a missed job after boot (Persistent=true). For scheduled scripts a timer beats cron: you see the next run (systemctl list-timers) and the last result. Explain a cron expression: crontab generator.