even better integration

config/routes.rb

@@ -1,4 +0,0 @@
-CarrierWave::Mongoid::Media.routes.draw do
-  get 'media/*path' => 'media#show'
-end
-

lib/carrierwave-mongoid-media/engine.rb

@@ -1,9 +1,27 @@
+require 'carrierwave'
+
 module CarrierWave
   module Mongoid
     class Media < ::Rails::Engine
-      initializer 'carrierwave_mongoid_media.carrierwave' do
+      DEFAULT_PREFIX = :media
+
+      class << self
+        attr_writer :prefix
+      end
+
+      def self.prefix
+        @prefix ||= DEFAULT_PREFIX
+      end
+
+      def self.routes(router, prefix = :media)
+        self.prefix = prefix
+
         CarrierWave.configure do |c|
-          c.grid_fs_access_url = '/media'
+          c.grid_fs_access_url = "/#{prefix}"
+        end
+
+        router.instance_exec do
+          get "#{prefix}/*path" => "media#show", :as => :media
         end
       end
     end