This is just a simple packaging of the code from https://github.com/gomini/go-mips32 and instructions from http://www.black-swift.com/forum/suggestion-box/59-go-1-4-2-on-black-swift on Alpine Linux. It gives you a setup configured for Go 1.4.2 targeting MIPS32 architecture. So you can simply:
docker run -t -i conoro/go-mips32:v1 /bin/sh
and then in the resulting shell do something like
go build helloworld.go
And the resulting helloworld executable should run on most MIPS32 boards. I have run generated binaries on a https://onion.io Omega board which uses the Atheros AR9331.