Execute commands once at a later time. Service atd (or atrun) should be running for the actual executions. More information: https://manned.org/at.
stdin
in 5 minutes (press Ctrl + D
when done):at now + 5 minutes
stdin
at 10:00 AM today:echo "./make_db_backup.sh" | at 1000
at -f path/to/file 9:30 PM Tue