[zemo]

it doesn't "compile from a url", the package name is just the url address. You still have a directory of downloaded packages analogous to Python's site-packages, and they don't update unless you explicitly update them. The difference is that if you say `go get github.com/whatever/foo` the package source will be downloaded to a location such as `/usr/local/go/src/pkg/github.com/whatever/foo`.