以下のようにcapybara-webkit のbundle時に失敗したときの対応メモ。 Installing capybara-webkit (0.8.0) with native extensions /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/installer.rb:482:in `build_extensions': ERROR: Failed to build gem native extension. (Gem::Installer::ExtensionBuildError) /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb Gem files will