
I was wanting to do this today to add `ruby@2.6` and it's a social rather than technical requirement (i.e. we don't want users to mess with their homebrew/core unless they know what they are doing) so allow overriding with `HOMEBREW_DEVELOPER` set.
Library
This directory contains all the code run by the official brew
and brew cask
commands in Homebrew
and all formulae (package descriptions) in taps (repositories containing formulae) in Taps
subdirectories.