gistfile1.txt

Fetching gem metadata from https://rubygems.org/.......
Fetching additional metadata from https://rubygems.org/..
Using rake 10.1.1
Using i18n 0.6.9
Using multi_json 1.8.4
Using activesupport 3.2.16
Using builder 3.0.4
Using activemodel 3.2.16
Using airbrake 3.1.15
Using json 1.8.1

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    /usr/bin/ruby2.1 extconf.rb
checking for libxml/parser.h... *** 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.

Provided configuration options:
	--with-opt-dir
	--without-opt-dir
	--with-opt-include
	--without-opt-include=${opt-dir}/include
	--with-opt-lib
	--without-opt-lib=${opt-dir}/lib
	--with-make-prog
	--without-make-prog
	--srcdir=.
	--curdir
	--ruby=/usr/bin/ruby2.1
	--with-zlib-dir
	--without-zlib-dir
	--with-zlib-include
	--without-zlib-include=${zlib-dir}/include
	--with-zlib-lib
	--without-zlib-lib=${zlib-dir}/lib
	--with-iconv-dir
	--without-iconv-dir
	--with-iconv-include
	--without-iconv-include=${iconv-dir}/include
	--with-iconv-lib
	--without-iconv-lib=${iconv-dir}/lib
	--with-xml2-dir
	--without-xml2-dir
	--with-xml2-include
	--without-xml2-include=${xml2-dir}/include
	--with-xml2-lib
	--without-xml2-lib=${xml2-dir}/lib
	--with-xslt-dir
	--without-xslt-dir
	--with-xslt-include
	--without-xslt-include=${xslt-dir}/include
	--with-xslt-lib
	--without-xslt-lib=${xslt-dir}/lib
	--with-libxslt-config
	--without-libxslt-config
	--with-pkg-config
	--without-pkg-config
	--with-libxml-2.0-config
	--without-libxml-2.0-config
	--with-pkg-config
	--without-pkg-config
	--with-libiconv-config
	--without-libiconv-config
	--with-pkg-config
	--without-pkg-config
/usr/lib/ruby/2.1.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
	from /usr/lib/ruby/2.1.0/mkmf.rb:587:in `try_cpp'
	from /usr/lib/ruby/2.1.0/mkmf.rb:1120:in `block in find_header'
	from /usr/lib/ruby/2.1.0/mkmf.rb:918:in `block in checking_for'
	from /usr/lib/ruby/2.1.0/mkmf.rb:351:in `block (2 levels) in postpone'
	from /usr/lib/ruby/2.1.0/mkmf.rb:321:in `open'
	from /usr/lib/ruby/2.1.0/mkmf.rb:351:in `block in postpone'
	from /usr/lib/ruby/2.1.0/mkmf.rb:321:in `open'
	from /usr/lib/ruby/2.1.0/mkmf.rb:347:in `postpone'
	from /usr/lib/ruby/2.1.0/mkmf.rb:917:in `checking_for'
	from /usr/lib/ruby/2.1.0/mkmf.rb:1119:in `find_header'
	from extconf.rb:116:in `<main>'

extconf failed, exit code 1

Gem files will remain installed in /home/app/input/vendor/bundle/ruby/2.1.0/gems/nokogiri-1.5.11 for inspection.
Results logged to /home/app/input/vendor/bundle/ruby/2.1.0/extensions/x86_64-linux/2.1.0/nokogiri-1.5.11/gem_make.out
An error occurred while installing nokogiri (1.5.11), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.5.11'` succeeds before bundling.