Ehh, that depends greatly on the computer architecture they’re running on. Modern silicon hardware is very succeptible (over the long term) to ionizing radiation like what is found in space. Without magnetic shielding like the Earth’s magnetic field, or a physical one like the atmosphere, they’d only get maaybe a few years around the Earth’s orbit. Jupiter also has quite a lot of radiation coming from it, so they’d have to set up either in interstellar travel or at some outer solar system lagrangian point to last any significant amount of time.
Or get good at self-service and manufacture, which requires resources that they could decide to just take from Earth.
It shouldn’t be significantly different from Linux, except maybe in what would be required to truly lock it down for a server. Assuming you’ll be installing normal server side stuff, all that should be nearly identical, especially if you use Docker or other containers/vm/interpreter based things.
Though it’s been yeeaaaars since I’ve touched a mac, so someone far more experienced will have to chime in if I’m off base!