By itself that would only schedule it before dbus.service if they are both queued to be started; but since we'd like to be using socket activation to lazy-start

By itself that would only schedule it before dbus.service if they are both queued to be started; but since we'd like to be using socket activation to lazy-start it, you'll also need to make sure it's queued when dbus.service is queued: [Install] WantedBy=dbus.service That's what I meant by "manually ordering nslcd.service before dbus.service".