gistfile1.txt

#(on a Macbook Air)
$ sudo gem install ./showoff-*.gem
Password:
Fetching: rack-1.6.0.gem (100%)
Successfully installed rack-1.6.0
Fetching: tilt-1.4.1.gem (100%)
Successfully installed tilt-1.4.1
Fetching: rack-protection-1.5.3.gem (100%)
Successfully installed rack-protection-1.5.3
Fetching: sinatra-1.4.5.gem (100%)
Successfully installed sinatra-1.4.5
Fetching: gli-2.12.2.gem (100%)
Successfully installed gli-2.12.2
Fetching: blankslate-3.1.3.gem (100%)
Successfully installed blankslate-3.1.3
Fetching: parslet-1.6.2.gem (100%)
Successfully installed parslet-1.6.2
Fetching: htmlentities-4.3.3.gem (100%)
Successfully installed htmlentities-4.3.3
Fetching: redcarpet-3.2.2.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing ./showoff-0.9.10.7.gem:
	ERROR: Failed to build gem native extension.

    /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby extconf.rb
creating Makefile

make "DESTDIR="
make: *** No rule to make target `/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include/ruby-2.0.0/universal-darwin13/ruby/config.h', needed by `autolink.o'.  Stop.


Gem files will remain installed in /Library/Ruby/Gems/2.0.0/gems/redcarpet-3.2.2 for inspection.
Results logged to /Library/Ruby/Gems/2.0.0/gems/redcarpet-3.2.2/ext/redcarpet/gem_make.out