Resources to get Ruby to interact with systemd through D-Bus

Great intro to systemd and dbus: Talking to systemd Through dbus with Python
Ruby library

Example:

require 'dbus'

sysbus = DBus.system_bus
systemd = sysbus['org.freedesktop.systemd1']['/org/freedesktop/systemd1']
manager = systemd['org.freedesktop.systemd1.Manager']
manager.GetUnitFileState('postgresql.service')