diff --git a/Setup.hs b/Setup.hs
--- a/Setup.hs
+++ b/Setup.hs
@@ -1,52 +1,2 @@
 import Distribution.Simple
-import Distribution.Simple.PreProcess
-import Distribution.Simple.Setup (ConfigFlags(..))
-import Distribution.PackageDescription (PackageDescription(..), FlagName(..))
-import Distribution.Simple.Utils ( rawSystemExitCode, findProgramVersion )
-import System.Exit
-import Distribution.Verbosity ( Verbosity )
-import Distribution.Simple.Utils (info, notice, installOrdinaryFiles)
-import Distribution.Simple.Setup
-import Distribution.Simple.Program (simpleProgram, Program(..))
-import Distribution.Simple.LocalBuildInfo
-import Data.Version
-import Control.Monad (when)
-import qualified Control.Exception as E
-
-main :: IO ()
-main = defaultMainWithHooks $ simpleUserHooks {
-      -- enable hsb2hs preprocessor for .hsb files
-      hookedPreProcessors = [ppBlobSuffixHandler]
-    , hookedPrograms = [(simpleProgram "hsb2hs"){
-                           programFindVersion = \verbosity fp ->
-                             findProgramVersion "--version" id verbosity fp }]
-    , postCopy = installManPage
-    }
-
-ppBlobSuffixHandler :: PPSuffixHandler
-ppBlobSuffixHandler = ("hsb", \_ lbi ->
-  PreProcessor {
-    platformIndependent = True,
-    runPreProcessor = mkSimplePreProcessor $ \infile outfile verbosity ->
-      do let embedData = case lookup (FlagName "embed_data_files")
-                              (configConfigurationsFlags (configFlags lbi)) of
-                              Just True -> True
-                              _         -> False
-         when embedData $
-            do info verbosity $ "Preprocessing " ++ infile ++ " to " ++ outfile
-               ec <- rawSystemExitCode verbosity "hsb2hs"
-                          [infile, infile, outfile]
-               case ec of
-                    ExitSuccess   -> return ()
-                    ExitFailure _ -> error "hsb2hs is needed to build this program"
-  })
-
-installManPage :: Args -> CopyFlags
-               -> PackageDescription -> LocalBuildInfo -> IO ()
-installManPage _ flags pkg lbi = do
-  let verbosity = fromFlag (copyVerbosity flags)
-  let copydest  = fromFlag (copyDest flags)
-  let mandest   = mandir (absoluteInstallDirs pkg lbi copydest)
-                     ++ "/man1"
-  notice verbosity $ "Copying man page to " ++ mandest
-  installOrdinaryFiles verbosity mandest [("man", "wai-middleware-content-type.1")]
+main = defaultMain
diff --git a/src/Network/Wai/Middleware/ContentType.hs b/src/Network/Wai/Middleware/ContentType.hs
--- a/src/Network/Wai/Middleware/ContentType.hs
+++ b/src/Network/Wai/Middleware/ContentType.hs
@@ -2,96 +2,148 @@
     OverloadedStrings
   #-}
 
+{- |
+Module      : Network.Wai.Middleware.ContentType
+Copyright   : (c) 2015 Athan Clark
+
+License     : BSD-3
+Maintainer  : athan.clark@gmail.com
+Stability   : experimental
+Portability : GHC
+
+Import this module to use all the application end-point combinators:
+
+> {-# LANGUAGE
+>     OverloadedStrings
+>   #-}
+>
+> import Network.Wai.Middleware.ContentType
+> import qualified Data.Text as T
+> import qualified Lucid as L
+>
+> myApp :: MonadIO m => MiddlewareT
+> myApp = fileExtsToMiddleware $ do
+>   text "Text!"
+>   json ("Json!" :: T.Text)
+>   lucid (L.toHtmlRaw ("Html!" :: T.Text))
+
+If you would like to embed a 'Network.Wai.Trans.MiddlewareT' as a response to
+a particular supported file extension / content type, import
+"Network.Wai.Middleware.ContentType.Middleware":
+
+> import Network.Wai.Middleware.ContentType
+> import Network.Wai.Middleware.ContentType.Middleware
+>
+> myApp = fileExtsToMiddleware $
+>   middleware Css myMiddleware
+-}
+
 module Network.Wai.Middleware.ContentType
-  ( module X
-  , fileExtsToMiddleware
+  ( -- * Utilities
+    fileExtsToMiddleware
   , lookupResponse
   , possibleFileExts
+  , allFileExts
+  , AcceptHeader
+  , -- * Re-Exports
+    module Network.Wai.Middleware.ContentType.Types
+  , module Network.Wai.Middleware.ContentType.Blaze
+  , module Network.Wai.Middleware.ContentType.Builder
+  , module Network.Wai.Middleware.ContentType.ByteString
+  , module Network.Wai.Middleware.ContentType.Cassius
+  , module Network.Wai.Middleware.ContentType.Clay
+  , module Network.Wai.Middleware.ContentType.Json
+  , module Network.Wai.Middleware.ContentType.Julius
+  , module Network.Wai.Middleware.ContentType.Lucid
+  , module Network.Wai.Middleware.ContentType.Lucius
+  , module Network.Wai.Middleware.ContentType.Text
+  , module Network.Wai.Middleware.ContentType.Pandoc
   ) where
 
-import Network.Wai.Middleware.ContentType.Types      as X hiding (tell)
-import Network.Wai.Middleware.ContentType.Blaze      as X
-import Network.Wai.Middleware.ContentType.Builder    as X
-import Network.Wai.Middleware.ContentType.ByteString as X
-import Network.Wai.Middleware.ContentType.Cassius    as X
-import Network.Wai.Middleware.ContentType.Clay       as X
-import Network.Wai.Middleware.ContentType.Json       as X
-import Network.Wai.Middleware.ContentType.Julius     as X
-import Network.Wai.Middleware.ContentType.Lucid      as X
-import Network.Wai.Middleware.ContentType.Lucius     as X
-import Network.Wai.Middleware.ContentType.Text       as X
-
 import Network.Wai.Trans
 import Network.HTTP.Types (HeaderName)
 import Network.HTTP.Media (mapAccept)
+import Network.Wai.Middleware.ContentType.Types hiding (tell')
+import Network.Wai.Middleware.ContentType.Blaze
+import Network.Wai.Middleware.ContentType.Builder
+import Network.Wai.Middleware.ContentType.ByteString
+import Network.Wai.Middleware.ContentType.Cassius
+import Network.Wai.Middleware.ContentType.Clay
+import Network.Wai.Middleware.ContentType.Json
+import Network.Wai.Middleware.ContentType.Julius
+import Network.Wai.Middleware.ContentType.Lucid
+import Network.Wai.Middleware.ContentType.Lucius
+import Network.Wai.Middleware.ContentType.Text
+import Network.Wai.Middleware.ContentType.Pandoc
 
 import qualified Data.ByteString as BS
 import qualified Data.Map as Map
-import Data.List (intersect, nub)
 import Data.Maybe (fromMaybe, catMaybes)
 import Data.Monoid
 import Control.Monad.Trans
+import Control.Monad
 
 
 type AcceptHeader = BS.ByteString
 
 -- | Turn a map of content types to middlewares, into a middleware.
-fileExtsToMiddleware :: MonadIO m =>
-                        FileExtListenerT (MiddlewareT m) m ()
-                     -> MiddlewareT m
+fileExtsToMiddleware :: ( MonadIO m
+                        ) => FileExtListenerT (MiddlewareT m) m ()
+                          -> MiddlewareT m
 fileExtsToMiddleware contentRoutes app req respond = do
   let mAcceptBS = Prelude.lookup ("Accept" :: HeaderName) $ requestHeaders req
-      fe = getFileExt req
-  mMiddleware <- lookupResponse mAcceptBS fe contentRoutes
+      mFe = getFileExt req
+  mMiddleware <- lookupResponse mAcceptBS mFe contentRoutes
   fromMaybe (app req respond) $ do
-    m <- mMiddleware
-    return $ m app req respond
+    mid <- mMiddleware
+    return $ mid app req respond
 
 -- | Given an HTTP @Accept@ header and a content type to base lookups off of, and
 -- a map of responses, find a response.
-lookupResponse :: Monad m =>
-                  Maybe AcceptHeader
-               -> FileExt
-               -> FileExtListenerT a m ()
-               -> m (Maybe a)
-lookupResponse mAcceptBS f fexts = do
+lookupResponse :: ( MonadIO m
+                  ) => Maybe AcceptHeader
+                    -> Maybe FileExt
+                    -> FileExtListenerT (MiddlewareT m) m ()
+                    -> m (Maybe (MiddlewareT m))
+lookupResponse mAcceptBS mFe fexts = do
   femap <- execFileExtListenerT fexts
-  return $ lookupFileExt mAcceptBS f femap
+  return $ lookupFileExt femap
   where
-    lookupFileExt mAccept k (FileExts xs) =
-      let attempts = maybe [Html,Text,Json,JavaScript,Css]
-                       (possibleFileExts k) mAccept
-      in getFirst $ foldMap (\f' -> First $ Map.lookup f' xs) attempts
+    lookupFileExt xs =
+      let attempts = maybe allFileExts (possibleFileExts mFe) mAcceptBS
+      in  getFirst $ foldMap (\f' -> First $ Map.lookup f' xs) attempts
 
 
 -- | Takes a file extension and an @Accept@ header, and returns the other
 -- file types handleable, in order of prescedence.
-possibleFileExts :: FileExt -> AcceptHeader -> [FileExt]
-possibleFileExts fe accept =
-  let computed = sortFE fe $ nub $ concat $
-        catMaybes [ mapAccept [ ("application/json" :: BS.ByteString, [Json])
-                              , ("application/javascript" :: BS.ByteString, [Json,JavaScript])
-                              ] accept
-                  , mapAccept [ ("text/html" :: BS.ByteString, [Html])
-                              ] accept
-                  , mapAccept [ ("text/plain" :: BS.ByteString, [Text])
-                              ] accept
-                  , mapAccept [ ("text/css" :: BS.ByteString, [Css])
-                              ] accept
-                  ]
-
-      wildcard = concat $
-        catMaybes [ mapAccept [ ("*/*" :: BS.ByteString, [Html,Text,Json,JavaScript,Css])
-                              ] accept
-                  ]
-  in if not (null wildcard) then wildcard else computed
+possibleFileExts :: Maybe FileExt -> AcceptHeader -> [FileExt]
+possibleFileExts mFe accept = if not (null wildcard) then wildcard else computed
   where
-    sortFE Html       xs = [Html, Text]             `intersect` xs
-    sortFE JavaScript xs = [JavaScript, Text]       `intersect` xs
-    sortFE Json       xs = [Json, JavaScript, Text] `intersect` xs
-    sortFE Css        xs = [Css, Text]              `intersect` xs
-    sortFE Text       xs = [Text]                   `intersect` xs
-    sortFE Markdown   xs = [Markdown, Text]         `intersect` xs
+    computed :: [FileExt]
+    computed = findFE $ concat $
+      catMaybes [ mapAccept [ ("application/json"       :: BS.ByteString, [Json])
+                            , ("application/javascript" :: BS.ByteString, [Json,JavaScript])
+                            ] accept
+                , mapAccept [ ("text/html" :: BS.ByteString, [Html])
+                            ] accept
+                , mapAccept [ ("text/plain" :: BS.ByteString, [Text, Markdown])
+                            ] accept
+                , mapAccept [ ("text/markdown" :: BS.ByteString, [Markdown])
+                            ] accept
+                , mapAccept [ ("text/css" :: BS.ByteString, [Css])
+                            ] accept
+                ]
 
+    wildcard :: [FileExt]
+    wildcard = findFE $ fromMaybe [] $ mapAccept [ ("*/*" :: BS.ByteString, allFileExts)
+                                                 ] accept
 
+
+    findFE :: [FileExt] -> [FileExt]
+    findFE xs = maybe xs (\fe -> fe <$ guard (fe `elem` xs)) mFe
+
+
+-- | All file extensions, in the order of preference
+allFileExts :: [FileExt]
+allFileExts = [Html,Text,Json,JavaScript,Css,Markdown]
 
diff --git a/src/Network/Wai/Middleware/ContentType/Blaze.hs b/src/Network/Wai/Middleware/ContentType/Blaze.hs
--- a/src/Network/Wai/Middleware/ContentType/Blaze.hs
+++ b/src/Network/Wai/Middleware/ContentType/Blaze.hs
@@ -14,6 +14,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @Html@ as the key in the map, and @"text/html"@ as the content type.
 blaze :: MonadIO m =>
@@ -57,6 +58,7 @@
   bytestringStatusWith f Html s hs $ LT.encodeUtf8 $ H.renderHtml i
 
 
+-- * 'Network.Wai.Response' Only
 
 blazeOnly :: H.Html -> Response
 blazeOnly = blazeOnlyStatusHeaders status200 [("Content-Type", "text/html")]
diff --git a/src/Network/Wai/Middleware/ContentType/Builder.hs b/src/Network/Wai/Middleware/ContentType/Builder.hs
--- a/src/Network/Wai/Middleware/ContentType/Builder.hs
+++ b/src/Network/Wai/Middleware/ContentType/Builder.hs
@@ -11,6 +11,7 @@
 import           Control.Monad.IO.Class
 
 
+-- * Lifted Combinators
 
 -- | A builder is ambiguous, therefore we require @RequestHeaders@ and a @FileExt@ to be explicitly
 -- supplied.
@@ -34,10 +35,11 @@
                   -> FileExtListenerT (MiddlewareT m) m ()
 builderStatusWith f e s hs i =
   let r = builderOnlyStatus s hs i in
-  FileExtListenerT $ tell $
-    FileExts $ Map.singleton e $ \_ _ respond -> respond (f r)
+  FileExtListenerT $ tell' $
+    Map.singleton e $ \_ _ respond -> respond (f r)
 
 
+-- * 'Network.Wai.Response' Only
 
 builderOnly :: RequestHeaders -> BU.Builder -> Response
 builderOnly = builderOnlyStatus status200
diff --git a/src/Network/Wai/Middleware/ContentType/ByteString.hs b/src/Network/Wai/Middleware/ContentType/ByteString.hs
--- a/src/Network/Wai/Middleware/ContentType/ByteString.hs
+++ b/src/Network/Wai/Middleware/ContentType/ByteString.hs
@@ -13,7 +13,7 @@
 import           Control.Monad.IO.Class
 
 
--- * Lifted @MiddlewareT@
+-- * Lifted Combinators
 
 -- | @ByteString@ is ambiguous - we need to know what @RequestHeaders@ and @FileExt@ should be associated.
 bytestring :: MonadIO m => FileExt -> RequestHeaders -> B.ByteString
@@ -40,7 +40,7 @@
   middleware fe $ \_ _ respond -> respond (f r)
 
 
--- * Raw @Response@s
+-- * 'Network.Wai.Response' Only
 
 bytestringOnly :: RequestHeaders -> B.ByteString -> Response
 bytestringOnly = bytestringOnlyStatus status200
diff --git a/src/Network/Wai/Middleware/ContentType/Cassius.hs b/src/Network/Wai/Middleware/ContentType/Cassius.hs
--- a/src/Network/Wai/Middleware/ContentType/Cassius.hs
+++ b/src/Network/Wai/Middleware/ContentType/Cassius.hs
@@ -12,6 +12,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @cassius@ as the key in the map, and @"cassius/plain"@ as the content type.
 cassius :: MonadIO m => Css -> FileExtListenerT (MiddlewareT m) m ()
@@ -54,7 +55,7 @@
   bytestringStatusWith f Css s hs $ LT.encodeUtf8 $ renderCss i
 
 
-
+-- * 'Network.Wai.Response' Only
 
 cassiusOnly :: Css -> Response
 cassiusOnly = cassiusOnlyStatusHeaders status200 [("Content-Type", "cassius/css")]
diff --git a/src/Network/Wai/Middleware/ContentType/Clay.hs b/src/Network/Wai/Middleware/ContentType/Clay.hs
--- a/src/Network/Wai/Middleware/ContentType/Clay.hs
+++ b/src/Network/Wai/Middleware/ContentType/Clay.hs
@@ -13,6 +13,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @Text@ as the key in the map, and @"text/css"@ as the content type.
 clay :: MonadIO m =>
@@ -58,6 +59,7 @@
 
 
 
+-- * 'Network.Wai.Response' Only
 
 clayOnly :: Config -> [App] -> Css -> Response
 clayOnly c as = clayOnlyStatusHeaders c as status200 [("Content-Type", "text/css")]
diff --git a/src/Network/Wai/Middleware/ContentType/Json.hs b/src/Network/Wai/Middleware/ContentType/Json.hs
--- a/src/Network/Wai/Middleware/ContentType/Json.hs
+++ b/src/Network/Wai/Middleware/ContentType/Json.hs
@@ -12,6 +12,7 @@
 
 
 
+-- * Lifted Combinators
 
 -- | Uses @Json@ as the key in the map, and @"application/json"@ as the content type.
 json :: ( A.ToJSON j
@@ -84,6 +85,7 @@
 
 
 
+-- * 'Network.Wai.Response' Only
 
 jsonOnly :: A.ToJSON j =>
             j -> Response
diff --git a/src/Network/Wai/Middleware/ContentType/Julius.hs b/src/Network/Wai/Middleware/ContentType/Julius.hs
--- a/src/Network/Wai/Middleware/ContentType/Julius.hs
+++ b/src/Network/Wai/Middleware/ContentType/Julius.hs
@@ -12,6 +12,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @julius@ as the key in the map, and @"application/javascript"@ as the content type.
 julius :: MonadIO m =>
@@ -55,6 +56,7 @@
   bytestringStatusWith f Json s hs $ LT.encodeUtf8 $ renderJavascript i
 
 
+-- * 'Network.Wai.Response' Only
 
 juliusOnly :: Javascript -> Response
 juliusOnly = juliusOnlyStatusHeaders status200 [("Content-Type", "application/javascript")]
diff --git a/src/Network/Wai/Middleware/ContentType/Lucid.hs b/src/Network/Wai/Middleware/ContentType/Lucid.hs
--- a/src/Network/Wai/Middleware/ContentType/Lucid.hs
+++ b/src/Network/Wai/Middleware/ContentType/Lucid.hs
@@ -11,6 +11,7 @@
 import           Control.Monad.Trans
 
 
+-- * Lifted Combinators
 
 -- | Uses the @Html@ key in the map, and @"text/html"@ as the content type.
 lucid :: MonadIO m => L.HtmlT m () -> FileExtListenerT (MiddlewareT m) m ()
@@ -55,6 +56,7 @@
 
 
 
+-- * 'Network.Wai.Response' Only
 
 lucidOnly :: Monad m =>
              L.HtmlT m () -> m Response
diff --git a/src/Network/Wai/Middleware/ContentType/Lucius.hs b/src/Network/Wai/Middleware/ContentType/Lucius.hs
--- a/src/Network/Wai/Middleware/ContentType/Lucius.hs
+++ b/src/Network/Wai/Middleware/ContentType/Lucius.hs
@@ -12,6 +12,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @lucius@ as the key in the map, and @"lucius/css"@ as the content type.
 lucius :: MonadIO m => Css -> FileExtListenerT (MiddlewareT m) m ()
@@ -54,6 +55,7 @@
   bytestringStatusWith f Css s hs $ LT.encodeUtf8 $ renderCss i
 
 
+-- * 'Network.Wai.Response' Only
 
 luciusOnly :: Css -> Response
 luciusOnly = luciusOnlyStatusHeaders status200 [("Content-Type", "lucius/css")]
diff --git a/src/Network/Wai/Middleware/ContentType/Middleware.hs b/src/Network/Wai/Middleware/ContentType/Middleware.hs
--- a/src/Network/Wai/Middleware/ContentType/Middleware.hs
+++ b/src/Network/Wai/Middleware/ContentType/Middleware.hs
@@ -10,4 +10,4 @@
               FileExt
            -> MiddlewareT m
            -> FileExtListenerT (MiddlewareT m) m ()
-middleware f m = tell $ FileExts $ Map.singleton f m
+middleware f m = tell' $ Map.singleton f m
diff --git a/src/Network/Wai/Middleware/ContentType/Pandoc.hs b/src/Network/Wai/Middleware/ContentType/Pandoc.hs
--- a/src/Network/Wai/Middleware/ContentType/Pandoc.hs
+++ b/src/Network/Wai/Middleware/ContentType/Pandoc.hs
@@ -13,6 +13,7 @@
 import           Control.Monad.Trans
 
 
+-- * Lifted Combinators
 
 -- | Uses the @Html@ key in the map, and @"text/html"@ as the content type.
 markdown :: MonadIO m => P.Pandoc -> FileExtListenerT (MiddlewareT m) m ()
@@ -51,11 +52,11 @@
 markdownStatusHeadersWith :: MonadIO m =>
                           (Response -> Response) -> Status -> RequestHeaders -> P.Pandoc
                        -> FileExtListenerT (MiddlewareT m) m ()
-markdownStatusHeadersWith f s hs i = do
+markdownStatusHeadersWith f s hs i =
   bytestringStatusWith f Html s hs . LT.encodeUtf8 . LT.pack $ P.writeMarkdown P.def i
 
 
-
+-- * 'Network.Wai.Response' Only
 
 markdownOnly :: P.Pandoc -> Response
 markdownOnly = markdownOnlyStatusHeaders status200 [("Content-Type", "text/markdown")]
diff --git a/src/Network/Wai/Middleware/ContentType/Text.hs b/src/Network/Wai/Middleware/ContentType/Text.hs
--- a/src/Network/Wai/Middleware/ContentType/Text.hs
+++ b/src/Network/Wai/Middleware/ContentType/Text.hs
@@ -12,6 +12,7 @@
 import           Control.Monad.IO.Class                  (MonadIO)
 
 
+-- * Lifted Combinators
 
 -- | Uses @Text@ as the key in the map, and @"text/plain"@ as the content type.
 text :: MonadIO m => LT.Text -> FileExtListenerT (MiddlewareT m) m ()
@@ -55,6 +56,7 @@
 
 
 
+-- * 'Network.Wai.Response' Only
 
 textOnly :: LT.Text -> Response
 textOnly = textOnlyStatusHeaders status200 [("Content-Type", "text/plain")]
diff --git a/src/Network/Wai/Middleware/ContentType/Types.hs b/src/Network/Wai/Middleware/ContentType/Types.hs
--- a/src/Network/Wai/Middleware/ContentType/Types.hs
+++ b/src/Network/Wai/Middleware/ContentType/Types.hs
@@ -2,7 +2,6 @@
     TypeFamilies
   , DeriveFunctor
   , FlexibleContexts
-  , DeriveTraversable
   , OverloadedStrings
   , FlexibleInstances
   , StandaloneDeriving
@@ -11,23 +10,33 @@
   , GeneralizedNewtypeDeriving
   #-}
 
+{- |
+Module      : Network.Wai.Middleware.ContentType.Types
+Copyright   : (c) 2015 Athan Clark
+
+License     : BSD-3
+Maintainer  : athan.clark@gmail.com
+Stability   : experimental
+Portability : GHC
+-}
+
 module Network.Wai.Middleware.ContentType.Types
-  ( FileExt (..)
+  ( -- * Types
+    FileExt (..)
   , getFileExt
   , toExt
-  , FileExts (..)
+  , FileExtMap
   , FileExtListenerT (..)
   , execFileExtListenerT
-  , mapFileExts
-  , tell
+  , -- * Utilities
+    tell'
   ) where
 
-import           Network.Wai
+import           Network.Wai.Trans
 import qualified Data.Text              as T
 import           Data.Map
-import           Data.Maybe (fromMaybe)
 import           Data.Monoid
-import           Data.Foldable
+import           Data.Url
 import           Control.Applicative
 import           Control.Monad.Base
 import           Control.Monad.Catch
@@ -42,8 +51,9 @@
 import           Control.Monad.Morph
 
 
-tell :: (Monoid w, MonadState w m) => w -> m ()
-tell x = do
+-- | Version of 'Control.Monad.Writer.tell' for 'Control.Monad.State.StateT'
+tell' :: (Monoid w, MonadState w m) => w -> m ()
+tell' x = do
   xs <- get
   put $ xs <> x
 
@@ -57,21 +67,14 @@
   deriving (Show, Eq, Ord)
 
 
-getFileExt :: Request -> FileExt
-getFileExt req = fromMaybe Html $ case pathInfo req of
-  [] -> Just Html
-  xs -> toExt $ T.pack $ getLastExt $ T.unpack $ last xs
-  where
-    getLastExt ts = evalState (foldrM go [] ts) False
-    go c soFar = do
-      sawPeriod <- get
-      if sawPeriod
-      then return soFar
-      else if c == '.'
-           then do put True
-                   return ('.' : soFar)
-           else return (c : soFar)
+-- | Gets the known file extension from a Request's 'Network.Wai.pathInfo'.
+getFileExt :: Request -> Maybe FileExt
+getFileExt req = case pathInfo req of
+  [] -> Nothing
+  xs -> toExt $ snd $ T.breakOn "." $ last xs
 
+-- | matches a file extension (__including__ it's prefix dot - @.html@ for example)
+--   to a known one.
 toExt :: T.Text -> Maybe FileExt
 toExt x | x `elem` htmls       = Just Html
         | x `elem` csss        = Just Css
@@ -88,21 +91,27 @@
     texts       = [".txt"]
     markdowns   = [".md", ".markdown"]
 
-newtype FileExts a = FileExts { unFileExts :: Map FileExt a }
-  deriving (Show, Eq, Monoid, Functor, Foldable, Traversable)
+type FileExtMap a = Map FileExt a
 
+-- | The monad for our DSL - when using the combinators, our result will be this
+--   type:
+--
+--   > myListener :: FileExtListenerT (MiddlewareT m) m ()
+--   > myListener = do
+--   >   text "Text!"
+--   >   json ("Json!" :: T.Text)
 newtype FileExtListenerT r m a =
-  FileExtListenerT { runFileExtListenerT :: StateT (FileExts r) m a }
+  FileExtListenerT { runFileExtListenerT :: StateT (FileExtMap r) m a }
     deriving ( Functor, Applicative, Alternative, Monad, MonadFix, MonadPlus, MonadIO
-             , MonadTrans, MonadReader r', MonadWriter w, MonadState (FileExts r)
+             , MonadTrans, MonadReader r', MonadWriter w, MonadState (FileExtMap r)
              , MonadCont, MonadError e, MonadBase b, MonadThrow, MonadCatch
-             , MonadMask, MonadLogger, MFunctor
+             , MonadMask, MonadLogger, MonadUrl b f, MFunctor
              )
 
 deriving instance (MonadResource m, MonadBase IO m) => MonadResource (FileExtListenerT r m)
 
 instance MonadTransControl (FileExtListenerT r) where
-  type StT (FileExtListenerT r) a = StT (StateT (FileExts r)) a
+  type StT (FileExtListenerT r) a = StT (StateT (FileExtMap r)) a
   liftWith = defaultLiftWith FileExtListenerT runFileExtListenerT
   restoreT = defaultRestoreT FileExtListenerT
 
@@ -113,14 +122,5 @@
   restoreM     = defaultRestoreM
 
 
-execFileExtListenerT :: Monad m => FileExtListenerT r m a -> m (FileExts r)
+execFileExtListenerT :: Monad m => FileExtListenerT r m a -> m (FileExtMap r)
 execFileExtListenerT xs = execStateT (runFileExtListenerT xs) mempty
-
-mapFileExts :: Monad m =>
-               (a -> b)
-            -> FileExtListenerT a m () -> FileExtListenerT b m ()
-mapFileExts f fl = do
-  femap <- lift $ execFileExtListenerT fl
-  tell $ f <$> femap
-
-
diff --git a/wai-middleware-content-type.cabal b/wai-middleware-content-type.cabal
--- a/wai-middleware-content-type.cabal
+++ b/wai-middleware-content-type.cabal
@@ -1,5 +1,5 @@
 Name:                   wai-middleware-content-type
-Version:                0.0.4
+Version:                0.1.0
 Author:                 Athan Clark <athan.clark@gmail.com>
 Maintainer:             Athan Clark <athan.clark@gmail.com>
 License:                BSD3
@@ -49,6 +49,7 @@
                       , text
                       , transformers
                       , transformers-base
+                      , urlpath >= 5.0.0.1
                       , wai
                       , wai-transformers >= 0.0.3
                       , wai-util