diff --git a/gravatar.cabal b/gravatar.cabal
--- a/gravatar.cabal
+++ b/gravatar.cabal
@@ -1,5 +1,5 @@
 name:                   gravatar
-version:                0.7.1
+version:                0.8.0
 author:                 Pat Brisbin <pbrisbin@gmail.com>
 maintainer:             Pat Brisbin <pbrisbin@gmail.com>
 license:                MIT
@@ -30,6 +30,7 @@
   build-depends:        base
                       , hspec
                       , gravatar
+                      , text
 
 source-repository head
   type:                 git
diff --git a/src/Network/Gravatar.hs b/src/Network/Gravatar.hs
--- a/src/Network/Gravatar.hs
+++ b/src/Network/Gravatar.hs
@@ -8,16 +8,16 @@
     , ForceDefault(..)
     , Rating(..)
     , Scheme (..)
-    , Default(..)
+    , Default(def)
     , defaultConfig
     ) where
 
+import Data.Default (Default(..))
 import Data.Digest.Pure.MD5 (md5)
-import Data.Default         (Default(..))
-import Data.List            (intercalate)
-import Data.Maybe           (catMaybes)
-import Data.Text            (Text)
-import Network.HTTP.Base    (urlEncode)
+import Data.List (intercalate)
+import Data.Maybe (catMaybes)
+import Data.Text (Text)
+import Network.HTTP.Base (urlEncode)
 
 import qualified Data.ByteString.Lazy.Char8 as C8
 import qualified Data.Text as T
@@ -35,44 +35,50 @@
 newtype ForceDefault = ForceDefault Bool
 
 instance GravatarParam ForceDefault where
-    toParam (ForceDefault b) = if b then Just ("f", "y") else Nothing
+    toParam (ForceDefault True) = Just ("f", "y")
+    toParam (ForceDefault False) = Nothing
 
 -- | Image to show when an avatar is not available
-data DefaultImg = Custom String -- ^ supply your own url
-                | NotFound      -- ^ do not load an image return a 404
-                | MM            -- ^ mystery man
-                | Identicon     -- ^ geometric pattern based on the hash
-                | MonsterId     -- ^ a generated monster
-                | Wavatar       -- ^ generated faces
-                | Retro         -- ^ generated, 8-bit arcade style pixelated face
+data DefaultImg
+    = Custom String -- ^ supply your own url
+    | NotFound      -- ^ do not load an image return a 404
+    | MM            -- ^ mystery man
+    | Identicon     -- ^ geometric pattern based on the hash
+    | MonsterId     -- ^ a generated monster
+    | Wavatar       -- ^ generated faces
+    | Retro         -- ^ generated, 8-bit arcade style pixelated face
 
 instance GravatarParam DefaultImg where
     toParam (Custom s) = Just ("d", urlEncode s)
-    toParam NotFound   = Just ("d", "404"      )
-    toParam MM         = Just ("d", "mm"       )
-    toParam Identicon  = Just ("d", "identicon")
-    toParam MonsterId  = Just ("d", "monsterid")
-    toParam Wavatar    = Just ("d", "wavatar"  )
-    toParam Retro      = Just ("d", "retro"    )
+    toParam NotFound = Just ("d", "404")
+    toParam MM = Just ("d", "mm")
+    toParam Identicon = Just ("d", "identicon")
+    toParam MonsterId = Just ("d", "monsterid")
+    toParam Wavatar = Just ("d", "wavatar")
+    toParam Retro = Just ("d", "retro")
 
 -- | Limit the returned images by rating
 data Rating = G | PG | R | X
 
 instance GravatarParam Rating where
-    toParam G  = Just ("r", "g" )
+    toParam G = Just ("r", "g")
     toParam PG = Just ("r", "pg")
-    toParam R  = Just ("r", "r" )
-    toParam X  = Just ("r", "x" )
+    toParam R = Just ("r", "r")
+    toParam X = Just ("r", "x")
 
 data GravatarOptions = GravatarOptions
-    { gSize         :: Maybe Size
-    , gDefault      :: Maybe DefaultImg
-    , gForceDefault :: ForceDefault
-    , gRating       :: Maybe Rating
-    , gScheme       :: Scheme
+    { gSize :: Maybe Size           -- ^ default @Nothing@
+    , gDefault :: Maybe DefaultImg  -- ^ default @Nothing@
+    , gForceDefault :: ForceDefault -- ^ default @False@
+    , gRating :: Maybe Rating       -- ^ default @Nothing@
+    , gScheme :: Scheme             -- ^ default @Https@
     }
 
-data Scheme = Http | Https | None
+-- | Scheme to use for image URLs
+data Scheme
+    = Http  -- ^ @http://@
+    | Https -- ^ @https://@
+    | None  -- ^ @//@
 
 instance Show Scheme where
   show Http = "http://"
@@ -85,34 +91,39 @@
 -- | Available for backwards compatability, using @def@ is advised
 defaultConfig :: GravatarOptions
 defaultConfig = GravatarOptions
-    { gSize         = Nothing
-    , gDefault      = Nothing
+    { gSize = Nothing
+    , gDefault = Nothing
     , gForceDefault = ForceDefault False
-    , gRating       = Nothing
-    , gScheme       = Https
+    , gRating = Nothing
+    , gScheme = Https
     }
 
 -- | Return the avatar for the given email using the provided options
 gravatar :: GravatarOptions -> Text -> String
-gravatar opts e = (show . gScheme $ opts) ++ "www.gravatar.com/avatar/"
-                                          ++ hashEmail e `addParams` opts
+gravatar opts e = concat
+    [ show $ gScheme opts
+    , "www.gravatar.com/avatar/"
+    , hashEmail e
+    , queryString opts
+    ]
 
 -- | <http://en.gravatar.com/site/implement/hash/>
 hashEmail :: Text -> String
-hashEmail = md5sum . T.toLower . T.strip
+hashEmail = show . md5 . C8.pack . T.unpack . T.toLower . T.strip
 
-    where
-        md5sum :: Text -> String
-        md5sum = show . md5 . C8.pack . T.unpack
+queryString :: GravatarOptions -> String
+queryString opts = case queryParts of
+    [] -> ""
+    ps -> "?" ++ intercalate "&" (map queryPart ps)
 
-addParams :: String -> GravatarOptions -> String
-addParams url opts = helper url . map (\(k,v) -> k ++ "=" ++ v)
-                   $ catMaybes [ toParam =<< gSize         opts
-                               , toParam =<< gDefault      opts
-                               , toParam   $ gForceDefault opts
-                               , toParam =<< gRating       opts
-                               ]
-    where
-        helper :: String -> [String] -> String
-        helper u [] = u
-        helper u l  = (++) u . (:) '?' $ intercalate "&" l
+  where
+    queryParts :: [(String, String)]
+    queryParts = catMaybes
+        [ toParam =<< gSize opts
+        , toParam =<< gDefault opts
+        , toParam   $ gForceDefault opts
+        , toParam =<< gRating opts
+        ]
+
+    queryPart :: (String, String) -> String
+    queryPart (k, v) = k ++ "=" ++ v