[Unit]
OnSuccess=success-failure-test-success.service
OnFailure=success-failure-test-failure.service

[Service]
Type=notify
Restart=always
ExecStart=bash -c 'test -f /tmp/success-failure-test-ran && touch /tmp/success-failure-test-ran2 && systemd-notify --ready && sleep infinity'
ExecStopPost=touch /tmp/success-failure-test-ran