diff --git a/Gemfile.lock b/Gemfile.lock
index ea52d76..6b94f78 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -35,6 +35,9 @@ GEM
       multi_json (~> 1.0)
     arel (3.0.2)
     builder (3.0.0)
+    carrierwave (0.6.2)
+      activemodel (>= 3.2.0)
+      activesupport (>= 3.2.0)
     database_cleaner (0.7.2)
     diff-lcs (1.1.3)
     erubis (2.7.0)
@@ -117,6 +120,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  carrierwave
   database_cleaner
   factory_girl_rails (~> 3.2.0)
   fuubar
diff --git a/lib/uploader.rb b/lib/uploader.rb
index 347e958..af6e4dc 100644
--- a/lib/uploader.rb
+++ b/lib/uploader.rb
@@ -21,7 +21,7 @@ def self.root_path
   
   def self.assets
     Dir[root_path.join('vendor/assets/javascripts/uploader/**', '*.{js,css}')].inject([]) do |list, path|
-      list << Pathname.new(path).relative_path_from(root_path.join('vendor/assets/javascripts'))
+      list << Pathname.new(path).relative_path_from(root_path.join('vendor/assets/javascripts')).to_s
       list
     end
   end
diff --git a/rails-uploader.gemspec b/rails-uploader.gemspec
index 6baee17..207fde8 100644
--- a/rails-uploader.gemspec
+++ b/rails-uploader.gemspec
@@ -19,4 +19,5 @@ Gem::Specification.new do |s|
   s.require_paths = ["lib"]
   
   s.add_development_dependency "sqlite3"
+  s.add_development_dependency "carrierwave"
 end
diff --git a/spec/dummy/app/models/article.rb b/spec/dummy/app/models/article.rb
new file mode 100644
index 0000000..741350d
--- /dev/null
+++ b/spec/dummy/app/models/article.rb
@@ -0,0 +1,5 @@
+class Article < ActiveRecord::Base
+  attr_accessible :content, :title
+  
+  has_one :picture, :as => :assetable, :dependent => :destroy
+end
diff --git a/spec/dummy/app/models/asset.rb b/spec/dummy/app/models/asset.rb
new file mode 100644
index 0000000..c2a5ee3
--- /dev/null
+++ b/spec/dummy/app/models/asset.rb
@@ -0,0 +1,27 @@
+# == Schema Information
+#
+# Table name: assets
+#
+#  id                :integer(4)      not null, primary key
+#  data_file_name    :string(255)     not null
+#  data_content_type :string(255)
+#  data_file_size    :integer(4)
+#  assetable_id      :integer(4)      not null
+#  assetable_type    :string(25)      not null
+#  type              :string(25)
+#  guid              :string(10)
+#  user_id           :integer(4)
+#  sort_order        :integer(4)      default(0)
+#  created_at        :datetime
+#  updated_at        :datetime
+#
+# Indexes
+#
+#  index_assets_on_assetable_type_and_assetable_id           (assetable_type,assetable_id)
+#  index_assets_on_user_id                                   (user_id)
+#
+class Asset < ActiveRecord::Base
+  attr_accessible :data
+  
+  belongs_to :assetable, :polymorphic => true 
+end
diff --git a/spec/dummy/app/models/picture.rb b/spec/dummy/app/models/picture.rb
new file mode 100644
index 0000000..254689a
--- /dev/null
+++ b/spec/dummy/app/models/picture.rb
@@ -0,0 +1,3 @@
+class Picture < Asset
+  mount_uploader :data, PictureUploader
+end
diff --git a/spec/dummy/app/uploaders/picture_uploader.rb b/spec/dummy/app/uploaders/picture_uploader.rb
new file mode 100644
index 0000000..d2899d8
--- /dev/null
+++ b/spec/dummy/app/uploaders/picture_uploader.rb
@@ -0,0 +1,55 @@
+# encoding: utf-8
+
+class PictureUploader < CarrierWave::Uploader::Base
+
+  # Include RMagick or MiniMagick support:
+  # include CarrierWave::RMagick
+  # include CarrierWave::MiniMagick
+
+  # Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
+  # include Sprockets::Helpers::RailsHelper
+  # include Sprockets::Helpers::IsolatedHelper
+
+  # Choose what kind of storage to use for this uploader:
+  storage :file
+  # storage :fog
+
+  # Override the directory where uploaded files will be stored.
+  # This is a sensible default for uploaders that are meant to be mounted:
+  def store_dir
+    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
+  end
+
+  # Provide a default URL as a default if there hasn't been a file uploaded:
+  # def default_url
+  #   # For Rails 3.1+ asset pipeline compatibility:
+  #   # asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
+  #
+  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
+  # end
+
+  # Process files as they are uploaded:
+  # process :scale => [200, 300]
+  #
+  # def scale(width, height)
+  #   # do something
+  # end
+
+  # Create different versions of your uploaded files:
+  # version :thumb do
+  #   process :scale => [50, 50]
+  # end
+
+  # Add a white list of extensions which are allowed to be uploaded.
+  # For images you might use something like this:
+  # def extension_white_list
+  #   %w(jpg jpeg gif png)
+  # end
+
+  # Override the filename of the uploaded files:
+  # Avoid using model.id or version_name here, see uploader/store.rb for details.
+  # def filename
+  #   "something.jpg" if original_filename
+  # end
+
+end
diff --git a/spec/dummy/config/application.rb b/spec/dummy/config/application.rb
index c608062..73b226e 100644
--- a/spec/dummy/config/application.rb
+++ b/spec/dummy/config/application.rb
@@ -4,6 +4,8 @@
 
 Bundler.require
 require "rails-uploader"
+require 'carrierwave'
+require 'carrierwave/orm/activerecord'
 
 module Dummy
   class Application < Rails::Application
diff --git a/spec/dummy/db/migrate/20120508093416_create_assets.rb b/spec/dummy/db/migrate/20120508093416_create_assets.rb
new file mode 100644
index 0000000..08dae40
--- /dev/null
+++ b/spec/dummy/db/migrate/20120508093416_create_assets.rb
@@ -0,0 +1,19 @@
+class CreateAssets < ActiveRecord::Migration
+  def change
+    create_table :assets do |t|
+      t.string   "data_file_name",                                 :null => false
+      t.string   "data_content_type"
+      t.integer  "data_file_size"
+      t.integer  "assetable_id",                                   :null => false
+      t.string   "assetable_type",    :limit => 25,                :null => false
+      t.string   "type",              :limit => 25
+      t.string   "guid",              :limit => 10
+      t.integer  "user_id"
+    
+      t.timestamps
+    end
+    
+    add_index "assets", ["assetable_type", "assetable_id"]
+    add_index "assets", ["user_id"]
+  end
+end
diff --git a/spec/dummy/db/migrate/20120508093830_create_articles.rb b/spec/dummy/db/migrate/20120508093830_create_articles.rb
new file mode 100644
index 0000000..1418a21
--- /dev/null
+++ b/spec/dummy/db/migrate/20120508093830_create_articles.rb
@@ -0,0 +1,10 @@
+class CreateArticles < ActiveRecord::Migration
+  def change
+    create_table :articles do |t|
+      t.string :title
+      t.text :content
+
+      t.timestamps
+    end
+  end
+end
diff --git a/spec/dummy/db/test.sqlite3 b/spec/dummy/db/test.sqlite3
index bf6b359..074e42a 100644
Binary files a/spec/dummy/db/test.sqlite3 and b/spec/dummy/db/test.sqlite3 differ
diff --git a/spec/factories/articles.rb b/spec/factories/articles.rb
new file mode 100644
index 0000000..8ba5160
--- /dev/null
+++ b/spec/factories/articles.rb
@@ -0,0 +1,8 @@
+# Read about factories at https://github.com/thoughtbot/factory_girl
+
+FactoryGirl.define do
+  factory :article do
+    title "MyString"
+    content "MyText"
+  end
+end
diff --git a/spec/factories/assets.rb b/spec/factories/assets.rb
new file mode 100644
index 0000000..ba72d78
--- /dev/null
+++ b/spec/factories/assets.rb
@@ -0,0 +1,6 @@
+# Read about factories at https://github.com/thoughtbot/factory_girl
+
+FactoryGirl.define do
+  factory :asset do
+  end
+end
diff --git a/spec/uploader_spec.rb b/spec/uploader_spec.rb
new file mode 100644
index 0000000..3991803
--- /dev/null
+++ b/spec/uploader_spec.rb
@@ -0,0 +1,18 @@
+require 'spec_helper'
+
+describe Uploader do
+  it "should be a Module" do
+    Uploader.should be_a(Module)
+  end
+  
+  it "should generate random string" do
+    value = Uploader.guid
+    value.should_not be_blank
+    value.size.should == 10
+  end
+  
+  it "should find all precompile assets" do
+    Uploader.assets.should_not be_nil
+    Uploader.assets.should include('uploader/jquery.fileupload.js')
+  end
+end