Correct me if I'm wrong here, but I am under the impression they're only non-deterministic in the practical sense (i.e, it produces this output on my machine, I

Correct me if I'm wrong here, but I am under the impression they're only non-deterministic in the practical sense (i.e, it produces this output on my machine, I can't know what minute differences there are on your machine), but that's not non-deterministic in the truest sense. If you have completely identical inputs you will get the exact same output, ergo, deterministic.