C:Siteshelios-master>gem install capybara-webkit -v '1.9.0'
Fetching: capybara-webkit-1.9.0.gem (100%)
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing capybara-webkit:
        ERROR: Failed to build gem native extension.

    current directory: C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/capybara-webkit-1.9.0
C:/RailsInstaller/Ruby2.2.0/bin/ruby.exe -r ./siteconf20161006-24264-1bccbjk.rb extconf.rb
/bin/sh: -c: line 1: syntax error: unexpected end of file
make: *** [sub-src-webkit_server-pro-make_first-ordered] Error 2
Command 'make' failed

current directory: C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/capybara-webkit-1.9.0
make "DESTDIR=" clean
/bin/sh: -c: line 1: syntax error: unexpected end of file
make: *** [sub-src-webkit_server-pro-clean-ordered] Error 2

current directory: C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/capybara-webkit-1.9.0
make "DESTDIR="
/bin/sh: -c: line 1: syntax error: unexpected end of file
make: *** [sub-src-webkit_server-pro-make_first-ordered] Error 2

make failed, exit code 2

Gem files will remain installed in C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/capybara-webkit-1.9.0 for inspection.
Results logged to C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/extensions/x86-mingw32/2.2.0/capybara-webkit-1.9.0/gem_make.out

gem "capybara-webkit", path: 'Path-To-The-Plugin-In-Your-Local-Machinecapybara-webkit-master'