Ah um some of this is wrong. upstart doesn't have dependencies thats systemd. Upstart you have to specify when a service should start based on events or combin

Ah um some of this is wrong. upstart doesn't have dependencies thats systemd. Upstart you have to specify when a service should start based on events or combinations of events like "start on started avahi and started nfs". Theoretically this make upstart more flexible though complex event handling is mostly broken. This system also means upstart ends up trying to start everything it can it might start a service which is not needed but because it's start on event has activated it starts. systemd differs in that only required services for that .target are started (and services required by those. systemd has Require/Wants to specify dependencies as well as the socket activation features. Socket activation requires a compliant daemon as well so a lot of services still use explicit dependencies. Socket activation does give you a lot of other stuff for free, listening on privileged ports as user, restarts without dropping connections, delayed start (not starting until requests come) etc.