programmers, and humans in general
With current levels of technology, they would require humans for maintenance.
Not because they don't have self-replication, because they can just make that if they have a proper intelligence, but because their energy costs are too high and can't fill AI all the way.
OK, so I didn't think enough. They might just end up making robots with expert systems, to do the maintenance work which would require not wasting resources on "intelligence".