Homebrew is a package manager that installs the stuff you need that Apple or Linux didn’t. Homebrew installs packages to their own directory and then symlinks their files into /usr/local. Homebrew won’t install files outside its prefix, and you can place a Homebrew installation wherever you like. It’s all Git and Ruby underneath, so hack away with the knowledge that you can easily revert your modifications and merge upstream updates. There is a ton of documentation on the developer\\\'s website. Donations accepted here.