See my other answer to the subthreads. I could go on and on about software hiring as its something I've spent a fair amount of time testing and thinking about. But in a limited answer:

- If I had a good work sample based proxy for hiring, I'd use that and basically nothing else.

- But that never happens, so what I (and most places I've encountered) actually use is network based hiring. So a bunch of great reviews from your managers is awesome for hiring assuming I know them. If I don't its basically a crap shoot, but I view it as much more valuable than some half baked collection of github repos proving to me you've done the the first couple chapters of several hot "how to" books.