diff --git a/hack2.cabal b/hack2.cabal
--- a/hack2.cabal
+++ b/hack2.cabal
@@ -1,5 +1,5 @@
 Name:                 hack2
-Version:              2011.6.10
+Version:              2011.6.19
 Build-type:           Simple
 Synopsis:             a Haskell Webserver Interface (V2)
 Description:
@@ -18,7 +18,7 @@
 
 library
   ghc-options: -Wall
-  build-depends: base >= 3 && < 5, data-default >= 0.2, bytestring
+  build-depends: base >= 3 && < 5, data-default >= 0.2, bytestring, enumerator < 5
   hs-source-dirs: src/
   exposed-modules:  
                     Hack2
diff --git a/readme.md b/readme.md
--- a/readme.md
+++ b/readme.md
@@ -78,7 +78,7 @@
 
 ### pick a backend
 
-    cabal install hack2-handler-happstack
+    cabal install hack2-handler-happstack-server
 
 ### Create a Hack app
 
@@ -108,22 +108,20 @@
 Middleware
 -----------
 
-(below is waiting to be finished)
-------------------------------------------
-
-
 ### demo usage of middleware
 
-install hack-contrib:
+install hack2-contrib:
 
-    cabal install hack-contrib
+    cabal install hack2-contrib
 
 put the following in `Main.hs`. This code uses the `URLMap` middleware to route both `/hello` and `/there` to the `say` application.
 
-    import Hack
-    import Hack.Handler.HappstackServer
-    import Hack.Contrib.Utils
-    import Hack.Contrib.Middleware.URLMap
+    {-# LANGUAGE OverloadedStrings #-}
+    
+    import Hack2
+    import Hack2.Handler.HappstackServer
+    import Hack2.Contrib.Utils
+    import Hack2.Contrib.Middleware.URLMap
     import Data.ByteString.Lazy.Char8 (pack)
     import Data.Default
     
@@ -137,7 +135,7 @@
 
 ### create a middleware
 
-inside Hack.hs:
+inside Hack2.hs:
 
     type Middleware = Application -> Application
 
@@ -149,9 +147,9 @@
 
 finally the source code of `Config.hs`:
 
-    module Hack.Contrib.Middleware.Config (config) where
+    module Hack2.Contrib.Middleware.Config (config) where
 
-    import Hack
+    import Hack2
 
     config :: (Env -> Env) -> Middleware
     config alter app = \env -> app (alter env)
@@ -159,7 +157,7 @@
 
 ### Use the middleware stack
 
-From `Hack.Contrib.Utils`:
+From `Hack2.Contrib.Utils`:
 
     -- usage: use [content_type, cache] app
     use :: [Middleware] -> Middleware
@@ -168,7 +166,7 @@
 Handlers
 --------
 
-Once an application is written using Hack, it should work on any web server that provides a Hack handler.
+Once an application is written using Hack2, it should work on any web server that provides a Hack2 handler.
 
 A handler should expose at least one function of type:
 
@@ -177,7 +175,7 @@
 Upgrade
 -------
 
-With every new release, any library links to hack should be recompiled against the new version, usually as simple as:
+With every new release, any library links to Hacks should be recompiled against the new version, usually as simple as:
 
     cabal install linked_lib --reinstall
 
diff --git a/src/Hack2.hs b/src/Hack2.hs
--- a/src/Hack2.hs
+++ b/src/Hack2.hs
@@ -1,3 +1,6 @@
+{-# LANGUAGE ExistentialQuantification #-}
+{-# LANGUAGE Rank2Types #-}
+
 module Hack2 where
 
 import Data.Default (def, Default)
@@ -5,7 +8,10 @@
 
 import Data.ByteString.Lazy (ByteString)
 import qualified Data.ByteString.Lazy as B
+import qualified Data.ByteString as Strict
 
+import Data.Enumerator (Enumerator, enumEOF)
+
 type Application = Env -> IO Response
 type Middleware  = Application -> Application
 
@@ -33,6 +39,14 @@
 instance Eq HackErrors where
   _ == _ = True
 
+newtype HackEnumerator = HackEnumerator { unHackEnumerator :: (forall a. Enumerator Strict.ByteString IO a) }
+
+instance Show HackEnumerator where
+  show _ = "HackEnumerator"
+
+instance Default HackEnumerator where
+  def = HackEnumerator enumEOF
+
 data Env = Env 
   {  requestMethod  :: RequestMethod
   ,  scriptName     :: ByteString
@@ -43,18 +57,18 @@
   ,  httpHeaders    :: [(ByteString, ByteString)]
   ,  hackVersion    :: (Int, Int, Int)
   ,  hackUrlScheme  :: HackUrlScheme
-  ,  hackInput      :: ByteString
+  ,  hackInput      :: HackEnumerator
   ,  hackErrors     :: HackErrors
   ,  hackHeaders    :: [(ByteString, ByteString)]
   }
-  deriving (Show, Eq)
+  deriving (Show)
 
 data Response = Response
   {  status   :: Int
   ,  headers  :: [(ByteString, ByteString)]
-  ,  body     :: ByteString
+  ,  body     :: HackEnumerator
   }
-  deriving (Show, Eq)
+  deriving (Show)
 
 instance Default RequestMethod where
   def = GET
@@ -67,7 +81,7 @@
     {
       status  = 200
     , headers = []
-    , body    = B.empty
+    , body    = def
     }
 
 instance Default Env where
@@ -82,9 +96,9 @@
       , httpHeaders   = def
       , hackVersion   = currentVersion
       , hackUrlScheme = def
-      , hackInput     = B.empty
+      , hackInput     = def
       , hackErrors    = def
       , hackHeaders   = def
     }
     where
-      currentVersion = (2011, 6, 10)
+      currentVersion = (2011, 6, 19)