Basic steps required to get your OSX Mountain Lion development machine ready for ruby / node / python

osx_dev.sh

# https://developer.apple.com/downloads/index.action
# 1.) download + install XCode from the app store
# 2.) download + install the XCode command line tools from the url above
# 3.) open Xcode for the first time and agree to the terms of use

# install homebrew and install libksba
ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go)"
brew doctor
brew update
brew install libksba

# install rvm -fix gcc and install ruby 2.0
curl -L https://get.rvm.io | bash -s stable --rails --autolibs=enabled
sudo ln -s /usr/bin/gcc /usr/bin/gcc-4.2
rvm install 1.9.3-p392

# install the fundamentals
brew install node
brew install phantomjs
brew install ack
brew install ctags

# install a few RubyGems
gem install bundler rails pg foreman thin --no-rdoc --no-ri

# install pip and virtualenvwrapper
sudo easy_install pip
sudo pip install virtualenvwrapper