"Nobody works here."
Translation:Nikt tu nie pracuje.
Double negatives work differently in Polish than in English. The translation is correct - 'nikt' requires to negate the verb.
In Polish grammar you can have double, triple, quadruple or even quintuple negation and still it means just negation.
EDIT sorry, this should have been under the PeterChusz's note.
"Nikt nigdzie i nigdy nic nie zrobił w tej sprawie." - Nobody ever and in any place did anything in that matter (Nobody never and nowhere didn't do nothing in that matter)
But it can't be "Nikt nie tu pracuje"? Does the "nie" always have to be next to the verb?
It should be next to what it negates, so you actually wrote "No one not here works", which does not make a lot of sense. But "On nie tu pracuje" would be acceptable (He works not here - but somewhere else).