title: gem install: ERROR: Failed to build gem native extension
body: <p>I am using Arch Linux and installed Ruby (this is version 2.0.0).</p>
  
  <p>When I installed Ruby it said I should add:</p>
  
  <pre><code>$(ruby -rubygems -e "puts Gem.user_dir")/bin
  </code></pre>
  
  <p>to my path, I added it to .bashrc</p>
  
  <p>When I try to gem install rails or any other gem it gives the Error: Failed to build gem native extension. this is the full error:</p>
  
  <pre><code>ERROR:  While executing gem ... (Gem::FilePermissionError)
      You don't have write permissions for the /usr/lib/ruby/gems/2.0.0 directory.
  [alexander@localhost ~]$ sudo gem install rails --no-user-install
  Building native extensions.  This could take a while...
  ERROR:  Error installing rails:
  ERROR: Failed to build gem native extension.
  
  /usr/bin/ruby extconf.rb
  creating Makefile
  
  make "DESTDIR="
  sh: make: command not found
  
  
  Gem files will remain installed in /usr/lib/ruby/gems/2.0.0/gems/atomic-1.1.10 for inspection.
  </code></pre>
  
  <p>When I look this error up I see that people solve this error by installing ruby-dev packages, however this does not exist for Arch Linux. Any other option that I can try?</p>
  
  <p>Thanks in advance!</p>