gem install simple-git-pair
git pair init
git pair nt ae # changes your git user.name to "Nicola Tesla & Alfred Einstein"
I usually put both names on the commit when I pair with someone. So we both take a credit and responsibility for written code. Unfortunately git doesn't provide a way to put more than one author on a commit out of the box. There are many gems that provide this functionality but the problem is that they change your email and github can't associate a commit with github account properly. I used one off script for a while that changes only your user.name and recently put it into a gem. Feel free to use it.