@nickrobison I think he means like in the [Formula Cookbook](https://github.com/Homebrew/homebrew/wiki/Formula-Cookbook#specifying-gems-python-modules-etc-as-dependencies). Or find the word "vendor" on that page. It suggests to look at the formula for [ansible](https://github.com/Homebrew/homebrew/blob/master/Library/Formula/ansible.rb). I'm not understanding how to do the same thing with this jbig2enc formula, but maybe if you give it a look.