Note src vs source in the original comment. Go forces you to change everything else to conform to gopath. I use go a lot and am used to it now but IMO that is a Bad Thing.
Put Go stuff in $GOPATH/src and Foo stuff in ~/foo/source. Problem solved. Go doesn't dictate where non-Go code lives...
This is the least of all problems.
So now your go stuff and foo stuff lives in different dirs based on which programming language it happens to use, not which project it is for. To you perhaps this is a non-problem, to others it appears to be and it is a recurring cause of grief for newcomers to go.