I'm not sure which Zones Of Thought book it was (probably Deepness in the Sky), but my favorite software joke in SciFi is when someone deep-diving into the syst

I'm not sure which Zones Of Thought book it was (probably Deepness in the Sky), but my favorite software joke in SciFi is when someone deep-diving into the system discovers that at the deepest layers timekeeping is still calculated from the UNIX epoch on the long lost human homeworld.