diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,10 @@
+2009.5.19
+---------
+
+### Feature
+
+* Compatible with hack 5.19
+
 2009.5.13
 ---------
 
diff --git a/hack-contrib.cabal b/hack-contrib.cabal
--- a/hack-contrib.cabal
+++ b/hack-contrib.cabal
@@ -1,5 +1,5 @@
 Name:                 hack-contrib
-Version:              2009.5.13
+Version:              2009.5.19
 Build-type:           Simple
 Synopsis:             Hack contrib
 Description:          Hack contrib
@@ -15,7 +15,7 @@
 
 library
   ghc-options: -Wall
-  build-depends: base, cgi, network, haskell98, old-locale, old-time, directory, filepath, containers, bytestring, ansi-wl-pprint, data-default >= 0.2, ansi-wl-pprint, unix, time, pureMD5, mps >= 2009.5.13, hack >= 2009.4.52
+  build-depends: base, cgi, network, haskell98, old-locale, old-time, directory, filepath, containers, bytestring, ansi-wl-pprint, data-default >= 0.2, ansi-wl-pprint, unix, time, pureMD5, mps >= 2009.5.13, hack >= 2009.5.19
   hs-source-dirs: src/
   exposed-modules:  
                     Hack.Contrib.Utils
@@ -28,12 +28,9 @@
                     Hack.Contrib.Middleware.File
                     Hack.Contrib.Middleware.Head
                     Hack.Contrib.Middleware.Hub
-                    Hack.Contrib.Middleware.Lambda
-                    Hack.Contrib.Middleware.Lucky
                     Hack.Contrib.Middleware.Mime
                     Hack.Contrib.Middleware.RawRouter
                     Hack.Contrib.Middleware.ShowExceptions
-                    Hack.Contrib.Middleware.ShowStatus
                     Hack.Contrib.Middleware.SimpleAccessLogger
                     Hack.Contrib.Middleware.SimpleRouter
                     Hack.Contrib.Middleware.Static
@@ -43,6 +40,10 @@
                     Hack.Contrib.Middleware.Config
                     Hack.Contrib.Middleware.Inspect
                     Hack.Contrib.Middleware.Debug
+                    Hack.Contrib.Middleware.Lambda
+                    Hack.Contrib.Middleware.Lucky
+                    Hack.Contrib.Middleware.ShowStatus
+
                     
 
                     
diff --git a/src/Hack/Contrib/Middleware/ETag.hs b/src/Hack/Contrib/Middleware/ETag.hs
--- a/src/Hack/Contrib/Middleware/ETag.hs
+++ b/src/Hack/Contrib/Middleware/ETag.hs
@@ -11,7 +11,6 @@
 import Prelude hiding ((.), (^), (>))
 
 import Data.Digest.Pure.MD5
-import Data.ByteString.Lazy.Char8 as C
 
 
 etag :: Middleware
@@ -25,6 +24,5 @@
   where 
     tag = 
           body
-        > C.pack
         > md5
         > show
diff --git a/src/Hack/Contrib/Middleware/File.hs b/src/Hack/Contrib/Middleware/File.hs
--- a/src/Hack/Contrib/Middleware/File.hs
+++ b/src/Hack/Contrib/Middleware/File.hs
@@ -18,6 +18,7 @@
 import System.Directory
 import System.FilePath
 
+import qualified Data.ByteString.Lazy.Char8 as B
 
 file :: Maybe String -> Middleware
 file root _ = \env -> do
@@ -47,7 +48,7 @@
     
     where 
       serving path = do
-        content <- path.b2u.read_binary_file
+        content <- path.B.readFile
         size <- path.b2u.file_size ^ from_i
         mtime_str <- path.b2u.file_mtime ^ httpdate
         
@@ -69,7 +70,7 @@
     .set_status 404
     .set_content_type _TextPlain
     .set_content_length (msg.length)
-    .set_body msg
+    .set_body (B.pack msg)
 
   where msg = "No permission: " ++ path ++ "\n"
 
@@ -79,7 +80,7 @@
     .set_status 404
     .set_content_type _TextPlain
     .set_content_length (msg.length)
-    .set_body msg
+    .set_body (B.pack msg)
   
   where msg = "File not found: " ++ path ++ "\n"
 
@@ -89,7 +90,7 @@
     .set_status 403
     .set_content_type _TextPlain
     .set_content_length (msg.length)
-    .set_body msg
+    .set_body (B.pack msg)
 
   where msg = "Forbidden\n"
   
diff --git a/src/Hack/Contrib/Middleware/Head.hs b/src/Hack/Contrib/Middleware/Head.hs
--- a/src/Hack/Contrib/Middleware/Head.hs
+++ b/src/Hack/Contrib/Middleware/Head.hs
@@ -1,14 +1,16 @@
 module Hack.Contrib.Middleware.Head (head) where
 
 import Hack
+import Hack.Contrib.Utils
 import Hack.Contrib.Response
 
 import MPSUTF8
 import Prelude hiding ((.), (^), (>), head)
+import qualified Data.ByteString.Lazy.Char8 as B
 
 head :: Middleware
 head app = \env -> do
   response <- app env
   if env.request_method.is HEAD 
-    then response .set_body "" .set_content_length 0 .return
+    then response .set_body B.empty .set_content_length 0 .return
     else response .return
diff --git a/src/Hack/Contrib/Middleware/Lambda.hs b/src/Hack/Contrib/Middleware/Lambda.hs
--- a/src/Hack/Contrib/Middleware/Lambda.hs
+++ b/src/Hack/Contrib/Middleware/Lambda.hs
@@ -5,6 +5,7 @@
 module Hack.Contrib.Middleware.Lambda (lambda) where
 
 import Hack
+import Hack.Contrib.Utils
 import Hack.Contrib.Response
 import Hack.Contrib.Constants
 
@@ -12,6 +13,8 @@
 import Prelude hiding ((.), (^), (>), (+))
 import Data.Default
 
+import qualified Data.ByteString.Lazy.Char8 as B
+
 data64 :: String
 data64 = [$here|
 
@@ -41,7 +44,7 @@
   if env.path_info.is "/lambda"
     then 
       return $ def
-        .set_body (data64.unzip64)
+        .set_body (data64.unzip64.B.pack)
         .set_content_type _TextHtml
         .set_status 200
     
diff --git a/src/Hack/Contrib/Middleware/Lucky.hs b/src/Hack/Contrib/Middleware/Lucky.hs
--- a/src/Hack/Contrib/Middleware/Lucky.hs
+++ b/src/Hack/Contrib/Middleware/Lucky.hs
@@ -5,6 +5,7 @@
 module Hack.Contrib.Middleware.Lucky (lucky) where
 
 import Hack
+import Hack.Contrib.Utils
 import Hack.Contrib.Response
 import Hack.Contrib.Constants
 
@@ -12,12 +13,14 @@
 import Prelude hiding ((.), (^), (>), (+))
 import Data.Default
 
+import qualified Data.ByteString.Lazy.Char8 as B
+
 lucky :: Middleware
 lucky app = \env -> do
   if env.path_info.is "/lucky"
     then 
       return $ def
-      .set_body (data64.unzip64)
+      .set_body (data64.unzip64.B.pack)
       .set_content_type _TextHtml
       .set_status 200
     
diff --git a/src/Hack/Contrib/Middleware/Mime.hs b/src/Hack/Contrib/Middleware/Mime.hs
--- a/src/Hack/Contrib/Middleware/Mime.hs
+++ b/src/Hack/Contrib/Middleware/Mime.hs
@@ -37,7 +37,7 @@
    ,  x     ".css"          "text/css"
    ,  x     ".csv"          "text/csv"
    ,  x     ".cxx"          "text/x-c"
-   ,  x     ".deb"          "application/x-debian-package"
+   ,  x     ".deb"          "application/x-debian-B.package"
    ,  x     ".der"          "application/x-x509-ca-cert"
    ,  x     ".diff"         "text/x-diff"
    ,  x     ".djv"          "image/vnd.djvu"
@@ -127,7 +127,7 @@
    ,  x     ".rb"           "text/x-script.ruby"
    ,  x     ".rdf"          "application/rdf+xml"
    ,  x     ".roff"         "text/troff"
-   ,  x     ".rpm"          "application/x-redhat-package-manager"
+   ,  x     ".rpm"          "application/x-redhat-B.package-manager"
    ,  x     ".rss"          "application/rss+xml"
    ,  x     ".rtf"          "application/rtf"
    ,  x     ".ru"           "text/x-script.ruby"
diff --git a/src/Hack/Contrib/Middleware/ShowExceptions.hs b/src/Hack/Contrib/Middleware/ShowExceptions.hs
--- a/src/Hack/Contrib/Middleware/ShowExceptions.hs
+++ b/src/Hack/Contrib/Middleware/ShowExceptions.hs
@@ -3,6 +3,7 @@
 module Hack.Contrib.Middleware.ShowExceptions (show_exceptions) where
 
 import Hack
+import Hack.Contrib.Utils
 import Hack.Contrib.Middleware.Hub
 
 import MPSUTF8
@@ -14,6 +15,7 @@
 import System.IO  
 import System.IO.Error
 
+import qualified Data.ByteString.Lazy.Char8 as B
 
 program :: String
 program = "ShowExceptions"
@@ -30,4 +32,4 @@
     handler log e = do
       let message = e.show
       Error. log message
-      return $ def { status = 500, body = message }
+      return $ def { status = 500, body = B.pack message }
diff --git a/src/Hack/Contrib/Middleware/ShowStatus.hs b/src/Hack/Contrib/Middleware/ShowStatus.hs
--- a/src/Hack/Contrib/Middleware/ShowStatus.hs
+++ b/src/Hack/Contrib/Middleware/ShowStatus.hs
@@ -23,6 +23,8 @@
 
 import Data.Maybe
 
+import qualified Data.ByteString.Lazy.Char8 as B
+
 show_status :: Middleware
 show_status app = \env -> do
   response <- app env
@@ -36,12 +38,13 @@
           i       = response.status
           message = i.show_status_message .fromMaybe (i.show)
           detail  = env.custom.get "hack.showstatus.detail" .fromMaybe message
-          result  = template message detail env response
+          result  = template message detail env response 
+                      .unescape_unicode_xml.u2b.B.pack
           size    = result.bytesize
       in
       return $ 
         response
-          .set_body (result.unescape_unicode_xml.u2b)
+          .set_body result
           .set_content_type _TextHtml
           .set_content_length size
     
diff --git a/src/Hack/Contrib/Middleware/SimpleRouter.hs b/src/Hack/Contrib/Middleware/SimpleRouter.hs
--- a/src/Hack/Contrib/Middleware/SimpleRouter.hs
+++ b/src/Hack/Contrib/Middleware/SimpleRouter.hs
@@ -15,6 +15,7 @@
 module Hack.Contrib.Middleware.SimpleRouter (route) where
 
 import Hack
+import Hack.Contrib.Utils
 
 import MPSUTF8
 import Prelude hiding ((.), (^), (>))
@@ -27,8 +28,8 @@
   let path             = env.path_info
       script           = env.script_name
       mod_env location = env 
-        { script_name  = script ++ location
-        , path_info    = path.drop (location.length)
+        { scriptName  = script ++ location
+        , pathInfo    = path.drop (location.length)
         }
   in
   case h.find (fst > (`isPrefixOf` path) ) of
diff --git a/src/Hack/Contrib/Request.hs b/src/Hack/Contrib/Request.hs
--- a/src/Hack/Contrib/Request.hs
+++ b/src/Hack/Contrib/Request.hs
@@ -11,12 +11,13 @@
 import Data.Maybe
 import Network.CGI.Protocol
 import Network.CGI.Cookie
-import Data.ByteString.Lazy.Char8 (pack, unpack)
+import Data.ByteString.Lazy.Char8 (ByteString)
+import qualified Data.ByteString.Lazy.Char8 as B
 
 -- import qualified Happstack.Server.MessageWrap as HM
 -- import qualified Happstack.Server.HTTP.Types as HT
 
-body :: Env -> String
+body :: Env -> ByteString
 body = hack_input
 
 scheme :: Env -> String
@@ -65,14 +66,14 @@
     .http
     .map_fst (upper > gsub "-" "_") -- cgi env use all cap letters
     .(("REQUEST_METHOD", env.request_method.show) : ) -- for cgi request
-    .flip decodeInput (env.body.pack)
+    .flip decodeInput (env.body)
     .fst
     .concatMap to_headers
   where
     to_headers (k, input) = case input.inputFilename of
-      Nothing -> [(k, input.inputValue.unpack)]
+      Nothing -> [(k, input.inputValue.B.unpack)]
       Just name -> 
-        [  (k, input.inputValue.unpack)
+        [  (k, input.inputValue.B.unpack)
         ,  ("hack_input_file_name_" ++ k, name)
         ]
 
@@ -94,7 +95,7 @@
 set_http k v env = env {http = env.http.put k v}
 
 set_custom :: String -> String -> Env -> Env
-set_custom k v env = env {custom = env.custom.put k v}
+set_custom k v env = env {hackHeaders = env.custom.put k v}
 
 url :: Env -> String
 url env =
diff --git a/src/Hack/Contrib/Response.hs b/src/Hack/Contrib/Response.hs
--- a/src/Hack/Contrib/Response.hs
+++ b/src/Hack/Contrib/Response.hs
@@ -10,7 +10,8 @@
 import Prelude hiding ((.), (^), (>), (+))
 
 import Data.Maybe
-
+import Data.ByteString.Lazy.Char8 (ByteString)
+import qualified Data.ByteString.Lazy.Char8 as B
 
 redirect :: String -> Maybe Int -> Response -> Response
 redirect target code = 
@@ -21,7 +22,7 @@
 finish r 
   | r.status.belongs_to [204, 304]
       = r .delete_header _ContentType
-          .set_body ""
+          .set_body B.empty
   | otherwise = r
         
 
@@ -43,7 +44,7 @@
 set_content_length :: Int -> Response -> Response
 set_content_length i r = r.set_header _ContentLength (i.show)
 
-set_body :: String -> Response -> Response
+set_body :: ByteString -> Response -> Response
 set_body s r = r { body = s }
 
 set_status :: Int -> Response -> Response
diff --git a/src/Hack/Contrib/Utils.hs b/src/Hack/Contrib/Utils.hs
--- a/src/Hack/Contrib/Utils.hs
+++ b/src/Hack/Contrib/Utils.hs
@@ -15,13 +15,10 @@
 import Control.Arrow ((<<<))
 import qualified Data.Map as M
 import Data.Time
-import Control.Monad (mplus, MonadPlus)
 import Data.Maybe
 import Data.List (lookup)
-
-(+) :: (MonadPlus m) => m a -> m a -> m a
-(+) = mplus
-infixl 8 +
+import Data.ByteString.Lazy.Char8 (ByteString)
+import qualified Data.ByteString.Lazy.Char8 as B
 
 empty_app :: Application
 empty_app = return def
@@ -37,10 +34,8 @@
 get :: String -> [(String, String)] -> Maybe String
 get = lookup
 
--- | note when calling bytesize, you are sure that the string
---   is in [char8] format anyway. so just call length
-bytesize :: String -> Int
-bytesize = length -- B.pack > B.length > from_i
+bytesize :: ByteString -> Int
+bytesize = B.length > from_i
 
 dummy_middleware :: Middleware
 dummy_middleware = id
@@ -69,3 +64,28 @@
 
 httpdate :: UTCTime -> String
 httpdate x = x.format_time "%a, %d %b %Y %X GMT"
+
+request_method    :: Env -> RequestMethod
+script_name       :: Env -> String
+path_info         :: Env -> String
+query_string      :: Env -> String
+server_name       :: Env -> String
+server_port       :: Env -> Int
+hack_version      :: Env -> [Int]
+hack_url_scheme   :: Env -> Hack_UrlScheme
+hack_input        :: Env -> ByteString
+hack_errors       :: Env -> HackErrors
+custom            :: Env -> [(String, String)]
+
+request_method  = requestMethod
+script_name     = scriptName
+path_info       = pathInfo
+query_string    = queryString
+server_name     = serverName
+server_port     = serverPort
+hack_version    = hack_version
+hack_url_scheme = hackUrlScheme
+hack_input      = hackInput
+hack_errors     = hackErrors
+custom          = hackHeaders
+