I don’t use Homebrew, given that Go is now written in Go, how does Homebrew bootstrap it when there are no binaries available? Does it download Go 1.4, builds it with a C compiler and uses that to build the latest version?

Based on this[1] it appears to be running this[2] bootstrap script, which I believe uses make.

[1] https://github.com/Homebrew/homebrew-core/blob/master/Formul... [2] https://github.com/golang/go/blob/master/src/bootstrap.bash

Sure, it's that simple until you need a specific non-default version. In cases like that I have found it easier to install from golang.org, that's all I was trying to say.