You may want to graduate to management or UML architect or be bogged down in valueless meetings, but that's not for me. I just want to make computers do magical things.
That's not what promotions are at Google. If you want to become a manager, that's called a ladder transfer, not a promotion. Promotions are basically for paying you more for making computers do more magical things. You are never asked to do anything other than software engineering, unless you want to do something other than software engineering.
(Note that software engineering is more than opening up an editor and typing in code, though.)