Rails Tutorial: nokogiri-1.5.2 error on bundle install

Question

After working through the RVM setup, rspec and guard sections of chapter 3 of the Ruby on Rails Tutorial, whenever I run bundle install I get the following error dump:

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

    /usr/bin/ruby1.9.1 extconf.rb 
/usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- mkmf (LoadError)
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from extconf.rb:5:in `<main>'


Gem files will remain installed in /home/dan/.bundler/tmp/17577/gems/nokogiri-1.5.2 for inspection.
Results logged to /home/dan/.bundler/tmp/17577/gems/nokogiri-1.5.2/ext/nokogiri/gem_make.out
An error occured while installing nokogiri (1.5.2), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.5.2'` succeeds before bundling.

In the gem_make.out:

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

    /usr/bin/ruby1.9.1 extconf.rb 
/usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file --mkmf (LoadError)
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from extconf.rb:5:in `<main>'

I've been debugging for a while now and I think I'm stuck. Help would be GREATLY appreciated!

Answer 1

You need the header files for compiling extension modules for Ruby.

You can get the proper version for your version of ruby with:

sudo aptitude install ruby-dev