<Installing CocoaPods If you are installing on macOS 10.9.0-10.9.2, you may run into an issue when RubyGems tries to install the json gem. To fix this follow these instructions. After upgrading from macOS 10.8 to 10.9 the installed CocoaPods gem doesn’t work anymore, even after re-installing the gem. To solve this, you might need to uninstall the gem first and then re-install. The gem might not be