diff --git a/.travis.yml b/.travis.yml
index 4c59258e5b..9f212a1f9b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,7 @@
 language: ruby
 
+before_install: gem install bundler
+
 before_script:
   - cd spec/dummy_app
   - bundle exec rake rails_admin:prepare_ci_env db:create db:migrate
diff --git a/Appraisals b/Appraisals
index 29daa4d770..15baa502e7 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,5 +1,6 @@
 appraise "rails-4.0" do
   gem 'rails', '~> 4.0.0'
+  gem 'sass-rails', '~> 4.0.3'
   gem 'devise', '>= 3.2'
   gem 'test-unit'
 end
diff --git a/Gemfile b/Gemfile
index c9cce1e266..8384a2c258 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,8 +7,7 @@ group :mongoid do
   gem 'mongoid', '~> 4.0.0'
   gem 'mongoid-paperclip', '>= 0.0.8', require: 'mongoid_paperclip'
   gem 'carrierwave-mongoid', '>= 0.6.3', require: 'carrierwave/mongoid'
-
-  gem 'refile-mongoid', '>= 0.0.1' if RUBY_VERSION >= '2.1.0'
+  gem 'refile-mongoid', '>= 0.0.1', platforms: [:ruby_21, :ruby_22]
 end
 
 group :active_record do
@@ -54,7 +53,7 @@ group :test do
   gem 'simplecov', '>= 0.9', require: false
   gem 'timecop', '>= 0.5'
 
-  if RUBY_VERSION >= '2.1.0'
+  platforms :ruby_21, :ruby_22 do
     gem 'refile', '~> 0.5', require: 'refile/rails'
     gem 'refile-mini_magick', '>= 0.1.0'
   end
diff --git a/gemfiles/rails_4.0.gemfile b/gemfiles/rails_4.0.gemfile
index bef2e484bd..163701b3b5 100644
--- a/gemfiles/rails_4.0.gemfile
+++ b/gemfiles/rails_4.0.gemfile
@@ -5,15 +5,14 @@ source "https://rubygems.org"
 gem "appraisal", ">= 2.0"
 gem "devise", ">= 3.2"
 gem "rails", "~> 4.0.0"
-gem "sass-rails", "~> 5.0"
+gem "sass-rails", "~> 4.0.3"
 gem "test-unit"
 
 group :mongoid do
   gem "mongoid", "~> 4.0.0"
   gem "mongoid-paperclip", ">= 0.0.8", :require => "mongoid_paperclip"
   gem "carrierwave-mongoid", ">= 0.6.3", :require => "carrierwave/mongoid"
-
-  gem "refile-mongoid", ">= 0.0.1" if RUBY_VERSION >= "2.1.0"
+  gem "refile-mongoid", ">= 0.0.1", :platforms => [:ruby_21, :ruby_22]
 end
 
 group :active_record do
@@ -59,7 +58,7 @@ group :test do
   gem "simplecov", ">= 0.9", :require => false
   gem "timecop", ">= 0.5"
 
-  if RUBY_VERSION >= "2.1.0"
+  platforms :ruby_21, :ruby_22 do
     gem "refile", "~> 0.5", :require => "refile/rails"
     gem "refile-mini_magick", ">= 0.1.0"
   end
diff --git a/gemfiles/rails_4.1.gemfile b/gemfiles/rails_4.1.gemfile
index a0b2847eb6..dc33edb6cf 100644
--- a/gemfiles/rails_4.1.gemfile
+++ b/gemfiles/rails_4.1.gemfile
@@ -5,14 +5,12 @@ source "https://rubygems.org"
 gem "appraisal", ">= 2.0"
 gem "devise", ">= 3.2"
 gem "rails", "~> 4.1.0"
-gem "sass-rails", "~> 5.0"
 
 group :mongoid do
   gem "mongoid", "~> 4.0.0"
   gem "mongoid-paperclip", ">= 0.0.8", :require => "mongoid_paperclip"
   gem "carrierwave-mongoid", ">= 0.6.3", :require => "carrierwave/mongoid"
-
-  gem "refile-mongoid", ">= 0.0.1" if RUBY_VERSION >= "2.1.0"
+  gem "refile-mongoid", ">= 0.0.1", :platforms => [:ruby_21, :ruby_22]
 end
 
 group :active_record do
@@ -58,7 +56,7 @@ group :test do
   gem "simplecov", ">= 0.9", :require => false
   gem "timecop", ">= 0.5"
 
-  if RUBY_VERSION >= "2.1.0"
+  platforms :ruby_21, :ruby_22 do
     gem "refile", "~> 0.5", :require => "refile/rails"
     gem "refile-mini_magick", ">= 0.1.0"
   end
diff --git a/gemfiles/rails_4.2.gemfile b/gemfiles/rails_4.2.gemfile
index 8e330fba4b..fac0acc700 100644
--- a/gemfiles/rails_4.2.gemfile
+++ b/gemfiles/rails_4.2.gemfile
@@ -11,8 +11,7 @@ group :mongoid do
   gem "mongoid", "~> 4.0.0"
   gem "mongoid-paperclip", ">= 0.0.8", :require => "mongoid_paperclip"
   gem "carrierwave-mongoid", ">= 0.6.3", :require => "carrierwave/mongoid"
-
-  gem "refile-mongoid", ">= 0.0.1" if RUBY_VERSION >= "2.1.0"
+  gem "refile-mongoid", ">= 0.0.1", :platforms => [:ruby_21, :ruby_22]
 end
 
 group :active_record do
@@ -58,7 +57,7 @@ group :test do
   gem "simplecov", ">= 0.9", :require => false
   gem "timecop", ">= 0.5"
 
-  if RUBY_VERSION >= "2.1.0"
+  platforms :ruby_21, :ruby_22 do
     gem "refile", "~> 0.5", :require => "refile/rails"
     gem "refile-mini_magick", ">= 0.1.0"
   end
diff --git a/lib/rails_admin/config/fields.rb b/lib/rails_admin/config/fields.rb
index b3b6e4a73f..33e84a2a2d 100644
--- a/lib/rails_admin/config/fields.rb
+++ b/lib/rails_admin/config/fields.rb
@@ -82,5 +82,5 @@ def self.register_factory(&block)
 require 'rails_admin/config/fields/factories/paperclip'
 require 'rails_admin/config/fields/factories/dragonfly'
 require 'rails_admin/config/fields/factories/carrierwave'
-require 'rails_admin/config/fields/factories/refile' if RUBY_VERSION >= '2.1.0'
+require 'rails_admin/config/fields/factories/refile'
 require 'rails_admin/config/fields/factories/association'
diff --git a/lib/rails_admin/config/fields/types/all.rb b/lib/rails_admin/config/fields/types/all.rb
index 7598f9d981..0099d8a142 100644
--- a/lib/rails_admin/config/fields/types/all.rb
+++ b/lib/rails_admin/config/fields/types/all.rb
@@ -10,7 +10,7 @@
 require 'rails_admin/config/fields/types/file_upload'
 require 'rails_admin/config/fields/types/paperclip'
 require 'rails_admin/config/fields/types/carrierwave'
-require 'rails_admin/config/fields/types/refile' if RUBY_VERSION >= '2.1.0'
+require 'rails_admin/config/fields/types/refile'
 require 'rails_admin/config/fields/types/float'
 require 'rails_admin/config/fields/types/has_and_belongs_to_many_association'
 require 'rails_admin/config/fields/types/has_many_association'
diff --git a/spec/controllers/rails_admin/main_controller_spec.rb b/spec/controllers/rails_admin/main_controller_spec.rb
index b0610fa823..a4f77b8c80 100644
--- a/spec/controllers/rails_admin/main_controller_spec.rb
+++ b/spec/controllers/rails_admin/main_controller_spec.rb
@@ -325,7 +325,7 @@ class TeamWithNumberedPlayers < Team
         field :paperclip_asset do
           delete_method :delete_paperclip_asset
         end
-        field :refile_asset if RUBY_VERSION >= '2.1.0'
+        field :refile_asset if defined?(Refile)
       end
       controller.params = HashWithIndifferentAccess.new(
         'field_test' => {
@@ -338,7 +338,7 @@ class TeamWithNumberedPlayers < Team
           'paperclip_asset' => 'test',
           'delete_paperclip_asset' => 'test',
           'should_not_be_here' => 'test',
-        }.merge(RUBY_VERSION >= '2.1.0' ? {'refile_asset' => 'test', 'remove_refile_asset' => 'test'} : {}),
+        }.merge(defined?(Refile) ? {'refile_asset' => 'test', 'remove_refile_asset' => 'test'} : {}),
       )
 
       controller.send(:sanitize_params_for!, :create, RailsAdmin.config(FieldTest), controller.params['field_test'])
@@ -352,7 +352,7 @@ class TeamWithNumberedPlayers < Team
           'retained_dragonfly_asset' => 'test',
           'paperclip_asset' => 'test',
           'delete_paperclip_asset' => 'test',
-        }.merge(RUBY_VERSION >= '2.1.0' ? {'refile_asset' => 'test', 'remove_refile_asset' => 'test'} : {}))
+        }.merge(defined?(Refile) ? {'refile_asset' => 'test', 'remove_refile_asset' => 'test'} : {}))
     end
 
     it 'allows for polymorphic associations parameters' do
diff --git a/spec/dummy_app/Gemfile b/spec/dummy_app/Gemfile
index 1a7111e3ff..04ba535f10 100644
--- a/spec/dummy_app/Gemfile
+++ b/spec/dummy_app/Gemfile
@@ -36,8 +36,7 @@ group :mongoid do
   gem 'mongoid', '~> 4.0.0.beta1'
   gem 'mongoid-paperclip', '>= 0.0.8', require: 'mongoid_paperclip'
   gem 'carrierwave-mongoid', '>= 0.6.3', require: 'carrierwave/mongoid'
-
-  gem 'refile-mongoid', '>= 0.0.1' if RUBY_VERSION >= '2.1.0'
+  gem 'refile-mongoid', '>= 0.0.1', platforms: [:ruby_21, :ruby_22]
 end
 
 gem 'carrierwave', '>= 0.8'
@@ -48,7 +47,7 @@ gem 'mlb', '>= 0.7'
 gem 'paperclip', '>= 3.4'
 gem 'rails_admin', path: '../../'
 
-if RUBY_VERSION >= '2.1.0'
+platforms :ruby_21, :ruby_22 do
   gem 'refile', '~> 0.5', require: 'refile/rails'
   gem 'refile-mini_magick', '>= 0.1.0'
 end
@@ -56,8 +55,8 @@ end
 # Gems used only for assets and not required
 # in production environments by default.
 group :assets do
-  gem 'sass-rails', '~> 4.0.0'
-  gem 'coffee-rails', '~> 4.0.0'
+  gem 'sass-rails', '~> 4.0.3'
+  gem 'coffee-rails', '~> 4.0'
 
   # See https://github.com/sstephenson/execjs#readme for more supported runtimes
   # gem 'therubyracer'
diff --git a/spec/dummy_app/app/active_record/field_test.rb b/spec/dummy_app/app/active_record/field_test.rb
index 1c6ef8eb74..f75e3dc3c7 100644
--- a/spec/dummy_app/app/active_record/field_test.rb
+++ b/spec/dummy_app/app/active_record/field_test.rb
@@ -12,5 +12,5 @@ class FieldTest < ActiveRecord::Base
   dragonfly_accessor :dragonfly_asset
   mount_uploader :carrierwave_asset, CarrierwaveUploader
 
-  attachment :refile_asset if RUBY_VERSION >= '2.1.0'
+  attachment :refile_asset if defined?(Refile)
 end
diff --git a/spec/dummy_app/app/mongoid/field_test.rb b/spec/dummy_app/app/mongoid/field_test.rb
index 51e1e121f5..34ff7eb097 100644
--- a/spec/dummy_app/app/mongoid/field_test.rb
+++ b/spec/dummy_app/app/mongoid/field_test.rb
@@ -51,7 +51,7 @@ class FieldTest
   dragonfly_accessor :dragonfly_asset
   mount_uploader :carrierwave_asset, CarrierwaveUploader
 
-  if RUBY_VERSION >= '2.1.0'
+  if defined?(Refile)
     extend Refile::Mongoid::Attachment
 
     field :refile_asset_filename
diff --git a/spec/rails_admin/config/fields/base_spec.rb b/spec/rails_admin/config/fields/base_spec.rb
index 370ad9c26e..2f20fc01c9 100644
--- a/spec/rails_admin/config/fields/base_spec.rb
+++ b/spec/rails_admin/config/fields/base_spec.rb
@@ -92,7 +92,7 @@ class CommentReversed < Tableless
       end
     end
 
-    if RUBY_VERSION >= '2.1.0'
+    if defined?(Refile)
       context 'of a Refile installation' do
         it 'is a _id field' do
           expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :refile_asset }.children_fields).to eq([:refile_asset_id, :refile_asset_filename, :refile_asset_size, :refile_asset_content_type])
@@ -266,7 +266,7 @@ class CommentReversed < Tableless
         expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :carrierwave_asset }.searchable_columns.collect { |c| c[:column] }).to eq(['field_tests.carrierwave_asset'])
       end
 
-      if RUBY_VERSION >= '2.1.0'
+      if defined?(Refile)
         it 'of refile should find the underlying column on the base table' do
           expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :refile_asset }.searchable_columns.collect { |c| c[:column] }).to eq(['field_tests.refile_asset_id'])
         end
@@ -303,7 +303,7 @@ class CommentReversed < Tableless
         expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :carrierwave_asset }.sortable).to eq(:carrierwave_asset)
       end
 
-      if RUBY_VERSION >= '2.1.0'
+      if defined?(Refile)
         it 'of refile should target the first children field' do
           expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :refile_asset }.searchable).to eq(:refile_asset_id)
           expect(RailsAdmin.config(FieldTest).fields.detect { |f| f.name == :refile_asset }.sortable).to eq(:refile_asset_id)
diff --git a/spec/rails_admin/config/fields/types/file_upload_spec.rb b/spec/rails_admin/config/fields/types/file_upload_spec.rb
index 3aa051e324..c0d9a63268 100644
--- a/spec/rails_admin/config/fields/types/file_upload_spec.rb
+++ b/spec/rails_admin/config/fields/types/file_upload_spec.rb
@@ -18,7 +18,7 @@
       expect(RailsAdmin.config(FieldTest).field(:carrierwave_asset).allowed_methods.collect(&:to_s)).to eq %w(carrierwave_asset remove_carrierwave_asset carrierwave_asset_cache)
       expect(RailsAdmin.config(FieldTest).field(:dragonfly_asset).allowed_methods.collect(&:to_s)).to eq %w(dragonfly_asset remove_dragonfly_asset retained_dragonfly_asset)
       expect(RailsAdmin.config(FieldTest).field(:paperclip_asset).allowed_methods.collect(&:to_s)).to eq %w(paperclip_asset delete_paperclip_asset)
-      expect(RailsAdmin.config(FieldTest).field(:refile_asset).allowed_methods.collect(&:to_s)).to eq %w(refile_asset remove_refile_asset) if RUBY_VERSION >= '2.1.0'
+      expect(RailsAdmin.config(FieldTest).field(:refile_asset).allowed_methods.collect(&:to_s)).to eq %w(refile_asset remove_refile_asset) if defined?(Refile)
     end
   end