at

Executes commands at a specified time. More information: https://man.archlinux.org/man/at.1.

• Open an at prompt to create a new set of scheduled commands, press Ctrl + D to save and exit:
  at {{hh:mm}}
• Execute the commands and email the result using a local mailing program such as Sendmail:
  at {{hh:mm}} -m
• Execute a script at the given time:
  at {{hh:mm}} -f {{path/to/file}}
• Display a system notification at 11pm on February 18th:
  echo "notify-send '{{Wake up!}}'" | at {{11pm}} {{Feb 18}}