Here’s how to set up a macOS terminal timer that uses notifications:

  1. Enable atrun:

    sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.atrun.plist
    

    If you’re on macOS Mojave or higher, you’ll also need to give atrun and Terminal full disk access. To do so:

    1. Open System Preferences > Security & Privacy > Privacy > Full Disk Access and click the lock to make changes.

    2. Click the + button to open the file dialog and use Command + Shift + G to go to /usr/libexec/atrun and open it.

    3. Repeat the process for /Applications/Utilities/Terminal.app.

  2. Install reattach-to-user-namespace:

    • Homebrew: brew install reattach-to-user-namespace
    • MacPorts: sudo port install tmux-pasteboard
  3. Add to ~/.profile:

    after() (
    	count=$1; shift
    	unit=$1; shift
    	title=`echo $* | sed 's/"/\\\"/g'`
    	at now + $count $unit <<-EOF
    	reattach-to-user-namespace osascript -e '
    	display notification with title "$title" sound name ""'
    	EOF
    )
    
  4. Enjoy:

    $ after 1 minute cookies are ready!