Somebody who has gone through years of difficult and strenuous education in
engineering,
architecture, or a similar field only to wind up with a mindless and repetitive job where they do one task on a computer drafting program
over and over again.
See: tool.
My cousin Curtis talked up the benefits of going into
engineering, and now spends 12 hours a day sitting at a
computer using a software program to draft diagrams of screws for
heavy machinery. He is a CAD monkey.