diff --git a/DEVELOPERS_NOTE.md b/DEVELOPERS_NOTE.md
index 031109d..650ce34 100644
--- a/DEVELOPERS_NOTE.md
+++ b/DEVELOPERS_NOTE.md
@@ -14,12 +14,11 @@
   * [hoe](https://github.com/seattlerb/hoe)
   * [hoe-gemspec](https://github.com/flavorjones/hoe-gemspec)
   * [rake-compiler](https://github.com/luislavena/rake-compiler)
-  * [gem-compile](https://github.com/frsyuki/gem-compile)
 
 
 ## Create ruby-opencv gem
 Run the following commands.
-When you use mingw32, use **MSYS console**, or when you use mswin32, 
+When you use mingw32, use **MSYS console**, or when you use mswin32,
 use [**Visual Studio Command Prompt**](http://msdn.microsoft.com/en-us/library/ms229859.aspx)
 instead of cmd.exe.
 
@@ -32,16 +31,34 @@ $ git ls-files > Manifest.txt
 $ rake gem:spec
 $ rake gem
 ```
-**ruby-opencv-x.y.z.gem** will be created in pkg/ directory.
+**ruby-opencv-x.y.z.gem** will be created in **pkg** directory.
 
-To create pre-build binaries, run the following commands in Windows.
+To create pre-build binaries, create a config file firstly:
 
-```
-$ cd pkg
-$ gem compile ruby-opencv-*.gem
+```yml
+# config.yml
+platform: mingw32
+rubies:
+  - C:/ruby-1.9.3-p392-mingw32/bin/ruby.exe
+  - C:/ruby-2.0.0-p0-mingw32/bin/ruby.exe
+extopts:
+  - --with-opencv-include=C:/opencv/build/include
+  - --with-opencv-lib=C:/opencv/build/x86/mingw/lib
 ```
 
-**ruby-opencv-x.y.z-x86-mingw32.gem** will be created when you use mingw32, or
+Entries are below:
+
+- **platform**: Target platform (e.g. mingw32, mswin32)
+- **rubies**: Array of target versions of ruby's paths (You can create fat gems if you specify multiple versions of ruby)
+- **extopts**: Array of options to be passed to **extconf.rb**
+
+Then, run the following command:
+
+```
+$ rake gem:precompile CONFIG=config.yml
+```
+
+**ruby-opencv-x.y.z-mingw32.gem** will be created when you use mingw32, or
 **ruby-opencv-x.y.z-x86-mswin32.gem** when you use mswin32.
 
 
diff --git a/Gemfile b/Gemfile
index b0e2a1a..1c6b08d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,6 +4,5 @@ group :development do
   gem "hoe"
   gem "hoe-gemspec"
   gem "rake-compiler"
-  gem "gem-compile"
 end
 
diff --git a/Manifest.txt b/Manifest.txt
index f8b850f..19a8c61 100644
--- a/Manifest.txt
+++ b/Manifest.txt
@@ -6,6 +6,7 @@ License.txt
 Manifest.txt
 README.md
 Rakefile
+config.yml
 examples/alpha_blend.rb
 examples/box.png
 examples/box_in_scene.png
diff --git a/Rakefile b/Rakefile
index 33bb37b..7f059d7 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,8 +1,13 @@
 # -*- mode: ruby; coding: utf-8 -*-
 require 'rubygems'
-require './lib/opencv/psyched_yaml'
+require "rubygems/ext"
+require "rubygems/installer"
 require 'hoe'
 require 'rake/extensiontask'
+require 'fileutils'
+require './lib/opencv/psyched_yaml'
+
+SO_FILE = 'opencv.so'
 
 Hoe.plugin :gemspec
 
@@ -16,14 +21,16 @@ hoespec = Hoe.spec 'ruby-opencv' do |s|
 
   s.readme_file  = 'README.md'
   s.history_file = 'History.txt'
+
   s.spec_extras = { :extensions => ['ext/opencv/extconf.rb'] }
+
   s.test_globs = ['test/test_*.rb']
   s.urls = ['https://github.com/ruby-opencv/ruby-opencv/']
 
   s.extra_dev_deps << ['rake-compiler', '>= 0'] << ['hoe-gemspec']
 
   Rake::ExtensionTask.new('opencv', spec) do |ext|
-    ext.lib_dir = File.join('lib', 'opencv')
+    ext.lib_dir = 'lib'
   end
 end
 
@@ -31,4 +38,53 @@ hoespec.spec.files.delete('.gemtest')
 
 Rake::Task[:test].prerequisites << :compile
 
+desc 'Create a pre-compiled gem'
+task 'gem:precompile' => ['gem'] do
+  tmp_dir = Dir.mktmpdir('tmp', '.')
+  gemfile = Dir.glob("pkg/*.gem")[0]
+  target_dir = File.join(tmp_dir, File.basename(gemfile, '.gem'))
+
+  installer = Gem::Installer.new(gemfile)
+  installer.unpack(target_dir)
+
+  gemspec = installer.spec
+  extension = gemspec.extensions[0]
+  gemspec.extensions.clear
+
+  config = ENV['CONFIG'] ?  YAML.load_file(ENV['CONFIG']) : {}
+  rubies = config['rubies'] || [Gem.ruby]
+  args = config['extopts'] || []
+  gemspec.platform = config['platform'] || Gem::Platform::CURRENT
+
+  multi = rubies.size > 1
+  rubies.each { |ruby|
+    lib_dir = 'lib'
+    if multi
+      major, minor, _ = `#{ruby} -e "print RUBY_VERSION"`.chomp.split('.')
+      lib_dir = File.join(lib_dir, [major, minor].join('.'))
+    end
+
+    make_cmd = (`#{ruby} -e "print RUBY_PLATFORM"` =~ /mswin/) ? 'nmake' : 'make'
+    Dir.chdir(target_dir) {
+      cmd = [ruby, extension, *args].join(' ')
+      results = []
+      Gem::Ext::ExtConfBuilder.run(cmd, results)
+      Gem::Ext::ExtConfBuilder.make('', results)
+
+      FileUtils.mkdir_p lib_dir
+      FileUtils.mv SO_FILE, lib_dir
+      sh "#{make_cmd} clean"
+    }
+
+    gemspec.files << File.join(lib_dir, SO_FILE)
+  }
+
+  Dir.chdir(target_dir) {
+    gemfile = Gem::Package.build(gemspec)
+    FileUtils.mv gemfile, File.dirname(__FILE__)
+  }
+
+  FileUtils.rm_rf tmp_dir
+end
+
 # vim: syntax=ruby
diff --git a/config.yml b/config.yml
new file mode 100644
index 0000000..4034d68
--- /dev/null
+++ b/config.yml
@@ -0,0 +1,7 @@
+platform: mingw32
+rubies:
+  - C:/ruby-1.9.3-p392-mingw32/bin/ruby.exe
+  - C:/ruby-2.0.0-p0-mingw32/bin/ruby.exe
+extopts:
+  - --with-opencv-include=C:/opencv/build/include
+  - --with-opencv-lib=C:/opencv/build/x86/mingw/lib
diff --git a/lib/opencv.rb b/lib/opencv.rb
index 068e5e7..d6ba2e1 100755
--- a/lib/opencv.rb
+++ b/lib/opencv.rb
@@ -1,3 +1,12 @@
 require (File.dirname(__FILE__) + '/opencv/version')
-require 'opencv.so'
 
+if RUBY_PLATFORM =~ /mingw|mswin/
+  major, minor, subminor = RUBY_VERSION.split('.')
+  begin
+    require "#{major}.#{minor}/opencv.so"
+  rescue LoadError
+    require 'opencv.so'
+  end
+else
+  require 'opencv.so'
+end