--- a/Gemfile	Sun Apr 06 01:23:15 2014 +0900
+++ b/Gemfile	Sun Apr 06 03:04:43 2014 +0900
@@ -9,7 +9,7 @@
 gem "pg", :platforms => :ruby
 gem "activerecord-jdbcpostgresql-adapter", :platforms => :jruby
 gem "jruby-openssl", :platforms => :jruby
-gem "actionpack-page_caching"
+gem "dalli"
 
 gem "sass-rails", "~> 4.0.0.rc1"
 

--- a/Gemfile.lock	Sun Apr 06 01:23:15 2014 +0900
+++ b/Gemfile.lock	Sun Apr 06 03:04:43 2014 +0900
@@ -10,8 +10,6 @@
       activesupport (= 4.1.0.rc2)
       rack (~> 1.5.2)
       rack-test (~> 0.6.2)
-    actionpack-page_caching (1.0.2)
-      actionpack (>= 4.0.0, < 5)
     actionview (4.1.0.rc2)
       activesupport (= 4.1.0.rc2)
       builder (~> 3.1)
@@ -40,6 +38,7 @@
     arel (5.0.0)
     bouncy-castle-java (1.5.0147)
     builder (3.2.2)
+    dalli (2.7.0)
     erubis (2.7.0)
     execjs (2.0.2)
     hike (1.2.3)
@@ -130,9 +129,9 @@
   ruby
 
 DEPENDENCIES
-  actionpack-page_caching
   activerecord-jdbcpostgresql-adapter
   anjlab-bootstrap-rails
+  dalli
   hooves
   jquery-rails
   jruby-openssl

--- a/app/controllers/pastes_controller.rb	Sun Apr 06 01:23:15 2014 +0900
+++ b/app/controllers/pastes_controller.rb	Sun Apr 06 03:04:43 2014 +0900
@@ -1,5 +1,5 @@
 class PastesController < ApplicationController
-  caches_page :show
+  before_action :lowercase_path, :only => :show
 
   # GET /1
   # GET /1.txt
@@ -7,10 +7,9 @@
     @paste = Paste.safe_find(params[:id])
     head :not_found and return unless @paste
 
-    expires_in 1.year, :public => true
     respond_to do |format|
-      format.html # show.html.erb
-      format.txt # show.txt.erb
+      format.html { cache }
+      format.txt { cache }
     end
   end
 
@@ -57,7 +56,7 @@
   def destroy
     @paste = Paste.safe_find(params[:id])
     if @paste.safe_destroy(params[:paste][:key])
-      expire_page :controller => 'pastes', :action => 'show', :id => @paste.id
+      uncache
       redirect_to root_path, :notice => "Paste ##{params[:id]} deleted"
     else
       flash.now[:alert] = @paste.errors.full_messages.to_sentence
@@ -66,6 +65,37 @@
   end
 
   private
+
+  def lowercase_path
+    correct_path = request.fullpath.downcase
+    redirect_to correct_path, :status => :moved_permanently  unless
+      correct_path == request.fullpath
+  end
+
+  def cache_key(format = request.format)
+    ext = case format
+          when Mime::TXT
+            ".txt"
+          when Mime::HTML
+            ""
+          else
+            ".unknown"
+          end
+    "pastes:#{@paste.to_param}#{ext}"
+  end
+
+  def cache
+    Rails.cache.fetch cache_key, :raw => true do
+      render_to_string :show
+    end
+  end
+
+  def uncache
+    [Mime::TXT, Mime::HTML, "others"].each do |format|
+      Rails.cache.delete cache_key(format)
+    end
+  end
+
   def paste_params
     params.require(:paste).permit(:paste, :paste_gzip, :paste_gzip_base64, :is_private, :key)
   end

--- a/config/application.rb	Sun Apr 06 01:23:15 2014 +0900
+++ b/config/application.rb	Sun Apr 06 03:04:43 2014 +0900
@@ -63,13 +63,13 @@
     # Version of your assets, change this if you want to expire all your assets
     config.assets.version = '1.0'
 
-    # Save cache in different location to avoid collision.
-    config.action_controller.page_cache_directory = config.root.join('public', 'cache')
-
-    # Enable compression for page caches.
-    config.action_controller.page_cache_compression = :best_compression
-
     # No need to initialize application when precompiling assets
     config.assets.initialize_on_precompile = false
+
+    if ENV["ZP_MEMCACHE"]
+      config.cache_store = :dalli_store, ENV["ZP_MEMCACHE"].split(","), { :namespace => "zeropaste" }
+    else
+      config.cache_store = :null_store
+    end
   end
 end