The missing package manager for OS X
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
Paste that at a Terminal prompt.
The script explains what it will do and then pauses before it does it. There are more installation options here (needed on 10.5).
Homebrew installs the stuff you need that Apple didn’t.
Homebrew installs packages to their own directory and then symlinks their files into
Homebrew won’t install files outside its prefix, and you can place a Homebrew installation wherever you like.
Trivially create your own Homebrew packages.
It's all git and ruby underneath, so hack away with the knowledge that you can easily revert your modifications and merge upstream updates.
Homebrew formulae are simple Ruby scripts:
Homebrew complements OS X. Install your gems with
gem, and their dependencies with