And Solaris SMF. There basically seem to be ~three generations of unix init:

1. Agglutination of shell scripts

2. "Oh wow, this is getting annoying"-phase: Wrapper for scripts (SRC SMC openrc etc pp)

3. Service supervision daemons (SMF, launchd, systemd)

Probably. I don't think systemd is a mere "Service supervision daemon", but I'm not in the mood for a can of worms today.