One of the 3 or so most senior engineers at Google is Sanjay Ghemawat (http://research.google.com/pubs/SanjayGhemawat.html http://research.google.com/pubs/Sanja

One of the 3 or so most senior engineers at Google is Sanjay Ghemawat (http://research.google.com/pubs/SanjayGhemawat.html http://research.google.com/pubs/SanjayGhemawat.html). I always joke that it must be a pseudonym for a group of at least 10 people, judging from the number of files in our core libraries that have his name as the author. That guy is a machine, and it's very good code too. So it's definitely possible to be a very senior engineer and still write code.