diff --git a/src/Trasa/Server.hs b/src/Trasa/Server.hs
--- a/src/Trasa/Server.hs
+++ b/src/Trasa/Server.hs
@@ -8,12 +8,14 @@
 {-# OPTIONS_GHC -Wall -Werror #-}
 module Trasa.Server
   ( TrasaT
+  , TrasaEnv(..)
   , runTrasaT
   , mapTrasaT
   , serveWith
   ) where
 
-import Control.Monad (join)
+import Control.Monad (join, MonadPlus(..))
+import Control.Applicative (liftA2, Alternative(..))
 import Data.Traversable (for)
 import Data.Functor.Identity
 
@@ -36,8 +38,14 @@
 
 type Headers = M.Map (CI BS.ByteString) T.Text
 
+data TrasaEnv = TrasaEnv
+  { trasaHeaders :: Headers
+  , trasaQueryString :: QueryString
+  , trasaRequestBody :: BS.ByteString
+  }
+
 newtype TrasaT m a = TrasaT
-  { unTrasaT :: ExceptT TrasaErr (StateT Headers (ReaderT Headers m)) a
+  { unTrasaT :: ExceptT TrasaErr (StateT Headers (ReaderT TrasaEnv m)) a
   } deriving
   ( Functor
   , Applicative
@@ -45,16 +53,31 @@
   , MonadError TrasaErr
   , MonadIO
   , MonadState (M.Map (CI BS.ByteString) T.Text)
-  , MonadReader (M.Map (CI BS.ByteString) T.Text))
+  , MonadReader TrasaEnv
+  )
 
+instance (Monad m, Semigroup a) => Semigroup (TrasaT m a) where
+  (<>) = liftA2 (<>)
+
+instance (Monad m, Monoid a) => Monoid (TrasaT m a) where
+  mempty = pure mempty
+
+instance (Alternative m, Monad m) => Alternative (TrasaT m) where
+  empty = lift empty
+  a <|> b = catchError a (const b)
+
+instance (Monad m, Alternative m) => MonadPlus (TrasaT m)
+
 instance MonadTrans TrasaT where
   lift = TrasaT . lift . lift . lift
 
 runTrasaT
   :: TrasaT m a
   -> M.Map (CI BS.ByteString) T.Text -- ^ Headers
+  -> QueryString -- ^ Query string parameters
+  -> BS.ByteString -- ^ Request body
   -> m (Either TrasaErr a, M.Map (CI BS.ByteString) T.Text)
-runTrasaT trasa headers = (flip runReaderT headers . flip runStateT M.empty . runExceptT  . unTrasaT) trasa
+runTrasaT trasa headers queryStrings requestBody = (flip runReaderT (TrasaEnv headers queryStrings requestBody) . flip runStateT M.empty . runExceptT  . unTrasaT) trasa
 
 mapTrasaT :: (forall x. m x -> n x) -> TrasaT m a -> TrasaT n a
 mapTrasaT eta = TrasaT . mapExceptT (mapStateT (mapReaderT eta)) . unTrasaT
@@ -81,9 +104,11 @@
           Just accepts -> do
             content <- for (M.lookup hContentType headers >>= N.parseAccept . TE.encodeUtf8) $ \typ ->
               Content typ <$> WAI.strictRequestBody req
-            let url = Url (WAI.pathInfo req) (decodeQuery (WAI.queryString req))
+            requestBody <- WAI.getRequestBodyChunk req
+            let queryStrings = decodeQuery (WAI.queryString req)
+                url = Url (WAI.pathInfo req) queryStrings
                 dispatch = dispatchWith toMeta makeResponse madeRouter method accepts url content
-            runTrasaT dispatch headers >>= \case
+            runTrasaT dispatch headers queryStrings requestBody >>= \case
               (resErr,newHeaders) -> case join resErr of
                 Left (TrasaErr stat errBody) ->
                   respond (WAI.responseLBS stat (encodeHeaders newHeaders) errBody)
diff --git a/trasa-server.cabal b/trasa-server.cabal
--- a/trasa-server.cabal
+++ b/trasa-server.cabal
@@ -2,7 +2,7 @@
 name:
   trasa-server
 version:
-  0.4
+  0.5
 synopsis:
   Type safe web server
 description: