Fetching: pkg-config-1.1.7.gem (100%) Successfully installed pkg-config-1.1.7 Fetching: nokogiri-1.6.8.gem (100%) Building native extensions. This could take a while... ERROR: Error installing rails: ERROR: Failed to build gem native extension.
current directory: /var/lib/gems/2.3.0/gems/nokogiri-1.6.8/ext/nokogiri /usr/bin/ruby2.3 -r ./siteconf20161003-4423-1bf9irh.rb extconf.rb Using pkg-config version 1.1.7 checking if the C compiler accepts ... yes Building nokogiri using packaged libraries. Using mini_portile version 2.1.0 checking for gzdopen() in -lz... no zlib is missing; necessary for building libxml2 *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options.
Gem files will remain installed in /var/lib/gems/2.3.0/gems/nokogiri-1.6.8 for inspection. Results logged to /var/lib/gems/2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.6.8/gem_make.out