In practice, in my experience at least, pure channel implementations are rare. It's rather hard to do (although I'll admit that was one of the most fun things for me about Go: "how can I solve this problem purely using channels?"). Sadly much Go code is far from the mantra. I've even heard seasoned Go programmers pass along the "wisdom" if you're using channels you're doing it wrong" (implying you haven't built the correct abstraction). Most Go I've encountered sadly uses shared memory and waitgroups and run_once. I think there are performance reasons for this too or something "channels are slow".