anchor.diff:  assert stdenv.system == "x86_64-linux" || stdenv.system == "i686-linux";
   
   let
  -  version = "1.6.5";
  +  version = "1.7.2";
     rake = buildRubyGem {
       inherit ruby;
       name = "rake-10.3.2";
  
positive.code: 
    preFixup = ''
      # 'hide' the template file from shebang-patching
      chmod -x $out/opt/vagrant/embedded/gems/gems/bundler-1.6.6/lib/bundler/templates/Executable
      chmod -x $out/opt/vagrant/embedded/gems/gems/vagrant-1.6.5/plugins/provisioners/salt/bootstrap-salt.sh
    '';
  
    postFixup = ''
      chmod +x $out/opt/vagrant/embedded/gems/gems/bundler-1.6.6/lib/bundler/templates/Executable
      chmod +x $out/opt/vagrant/embedded/gems/gems/vagrant-1.6.5/plugins/provisioners/salt/bootstrap-salt.sh
    '';
  }
  
negative.code:     if stdenv.system == "x86_64-linux" then
        fetchurl {
          url    = "https://dl.bintray.com/mitchellh/vagrant/vagrant_${version}_x86_64.deb";
          sha256 = "0s1rwzpcp0nc7v04fvbd5vsqfm79q2v23sr9ahniw09lf5c1qzwx";
        }
      else
        fetchurl {
          url    = "https://dl.bintray.com/mitchellh/vagrant/vagrant_${version}_i686.deb";
          sha256 = "1yj8iyhsgj6j3r7p3ppmsz01j6vnxqb18rjhsbp2sz45kbfs1wxz";
        };
  
    meta = with stdenv.lib; {
      description = "A tool for building complete development environments";
      homepage    = http://vagrantup.com;
      license     = licenses.mit;
      maintainers = with maintainers; [ lovek323 globin ];
      platforms   = platforms.linux;
    };
  
  