I'd do that as a zsh plugin. If you do one that's oh-my-zsh compatible, it'll work with most of the frameworks, and you can install it by hand if you're running bare ZSH.

Then they just need to occasionally `git pull` to get updates to your company script collection.

I wrote a brief set of guidelines at https://github.com/unixorn/awesome-zsh-plugins/blob/master/W...

If you have them use a ZSH framework, (I recommend https://github.com/tarjoilija/zgen for load speed), the good ones can handle the periodic pulls for you automagically.