Brew tap for GBCC
brew install --HEAD philj56/gbcc/gbcc
Or brew tap philj56/gbcc
and then brew install --HEAD gbcc
.
Or install via URL (which will not receive updates):
brew install --HEAD https://raw.githubusercontent.com/philj56/homebrew-gbcc/master/Formula/gbcc.rb
brew help
, man brew
or check Homebrew's documentation.