gistfile1.txt

sudo gem install iconv
Fetching: iconv-1.0.4.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing iconv:
	ERROR: Failed to build gem native extension.

    /usr/bin/ruby2.2 -r ./siteconf20160713-16753-14nr0ln.rb extconf.rb
mkmf.rb can't find header files for ruby at /usr/lib/ruby/include/ruby.h

extconf failed, exit code 1

Gem files will remain installed in /var/lib/gems/2.2.0/gems/iconv-1.0.4 for inspection.
Results logged to /var/lib/gems/2.2.0/extensions/x86_64-linux/2.2.0/iconv-1.0.4/gem_make.out