[TezzellEnt]

I've seen that the best way to grow your company's culture is to hire people that your own employees recommend. That is, if you want to build your culture you'll want to hire people that your current employees have worked with before.

Brian didn't mention it, but I'll bet that their first engineer hire recommended friends or colleagues in the industry that s/he worked with in the past - whether that was at another company or even in an open source arena. From there, that network grew, much like a network of your first 100 people that love your product grows.