I am not really sold on the master should be stable, major releases should be on different URLs. Installing stuff directly from github.com someone's master branch sounds like an easy way to get random SIGSEGV and similar hard to debug issues.
Michael from Gemfury here. We've been using Golang for a couple of years with a dependency manager that we've built internally and will shortly release to the public. If you'd like to try it, check it out here: https://melody.sh/docs