I've done a couple of interviews recently for a C++ developer role, none had GitHub pages. It didn't negatively effect them, they were rated on their strengths

I've done a couple of interviews recently for a C++ developer role, none had GitHub pages. It didn't negatively effect them, they were rated on their strengths from their CV's, interview and a take home programming task but I'd have loved to have seen at least one repo of work. You don't necessarily need to be using GitHub to produce OSS to the level of something like Rails, but even a micro library would have awesome. It gives you just a little bit more data to look at when you're considering options.