Sounds exactly like a senior sw engineer I work with. The guy is incredibly productive and an excellent mentor. He hates social networks, doesn't have a github account, and all his best code (and mine) are locked up in private IP that can't be thrown into a portfolio.

I'd hope that not having a portfolio isn't a deal breaker in Jeff's hiring approach. My co-worker would be able to give any interviewer a very interesting and detailed discussion about past projects.