In my instance of this problem, my company requires encryption in flight for EVERYTHING, and we use Stash to manage our git repos. In order to have access, you must have an SSH key registered on your Stash user account, and then you must have permission to engage with a given project or repository.
We want to set up a unified development environment on an AWS box so we don't continuously run into problems onboarding new people and setting up their environments again and again (too busy to script up at present time), but Git makes this surprisingly tough. Is there a way to have multiple SSH keys tied into one Git installation and simply change users with git config user.name/email?