Systemd Alarm Clock

http://joeyh.name/blog/entry/a_programmable_alarm_clock_using_systemd/

>>32
If you want a service management demon, there are a few of those around that are not systemd.

>>34

these supposedly optional components don't expose any standard interface

The standard interface for systemd is through the configuration files. External programs are not supposed to interface with the internal systemd interfaces.