Yes, this can be done, and it's actually necessary when you want the share point available to something like servers which are started and run without a user logged in.
I did this years ago for something, and just again needed to do it, but my notes were inadequate. After a lot of fiddling, I've written enough details out so that I'll never have to do that again (I hope).
You combine launchd and a script, but there's some details that many other posts fail to mention. I captured them (at least for my setup).
All the nitty gritty details are here: