diff --git a/Hack/Handler/CGI.hs b/Hack/Handler/CGI.hs
--- a/Hack/Handler/CGI.hs
+++ b/Hack/Handler/CGI.hs
@@ -9,6 +9,8 @@
 import Data.Maybe (fromMaybe)
 import qualified Data.ByteString.Lazy as BS
 import Data.Word (Word8)
+import Control.Arrow (first)
+import Data.Char (toLower)
 
 safeRead :: Read a => a -> String -> a
 safeRead d s =
@@ -36,6 +38,7 @@
         qstring = lookup' "QUERY_STRING" vars
         servername = lookup' "SERVER_NAME" vars
         serverport = safeRead 80 $ lookup' "SERVER_PORT" vars
+        contentLength = safeRead 0 $ lookup' "CONTENT_LENGTH" vars
     let env = def
             { requestMethod = rmethod
             , scriptName = sname
@@ -43,8 +46,8 @@
             , queryString = qstring
             , serverName = servername
             , serverPort = serverport
-            , http = vars
-            , hackInput = body'
+            , http = map (first cleanupVarName) vars
+            , hackInput = BS.take contentLength body'
             }
     res <- app env
     let h = headers res
@@ -74,3 +77,10 @@
     | fromEnum c < 256 = toEnum $ fromEnum c
     | otherwise = error $ "Out of bound character, value: " ++
                           show (fromEnum c)
+
+cleanupVarName :: String -> String
+cleanupVarName ('H':'T':'T':'P':'_':a:as) = a : helper' as where
+    helper' ('_':x:rest) = '-' : x : helper' rest
+    helper' (x:rest) = toLower x : helper' rest
+    helper' [] = []
+cleanupVarName x = x
diff --git a/hack-handler-cgi.cabal b/hack-handler-cgi.cabal
--- a/hack-handler-cgi.cabal
+++ b/hack-handler-cgi.cabal
@@ -1,5 +1,5 @@
 name:            hack-handler-cgi
-version:         0.0.0
+version:         0.0.1
 license:         BSD3
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>