diff --git a/apiary.cabal b/apiary.cabal
--- a/apiary.cabal
+++ b/apiary.cabal
@@ -1,5 +1,5 @@
 name:                apiary
-version:             1.4.2
+version:             1.4.3
 synopsis:            Simple and type safe web framework that generate web API documentation.
 description:
   Simple and type safe web framework that can be automatically generate API documentation.
@@ -88,8 +88,8 @@
                        Control.Monad.Apiary.Filter.Internal
                        Control.Monad.Apiary.Action.Internal
                        Control.Monad.Apiary.Filter.Internal.Capture.TH
-  build-depends:       base                 >=4.6   && <4.8
-                     , template-haskell     >=2.8   && <2.10
+  build-depends:       base                 >=4.6   && <4.9
+                     , template-haskell     >=2.8   && <2.11
 
                      , transformers         >=0.2   && <0.5
                      , transformers-base    >=0.4   && <0.5
@@ -104,8 +104,8 @@
                      , bytestring           >=0.10  && <0.11
                      , bytestring-read      >=0.2   && <0.3
                      , blaze-builder        >=0.3   && <0.5
-                     , blaze-html           >=0.7   && <0.8
-                     , blaze-markup         >=0.6   && <0.7
+                     , blaze-html           >=0.7   && <0.9
+                     , blaze-markup         >=0.6   && <0.8
                      , case-insensitive     >=1.1   && <1.3
                      , vault                >=0.3   && <0.4
 
@@ -122,7 +122,6 @@
                      , web-routing          >=0.6   && <0.7
                      , types-compat         >=0.1   && <0.2
 
-  default-extensions:  OverlappingInstances
   hs-source-dirs:      src
   ghc-options:         -O2 -Wall
   ghc-prof-options:    -O2 -Wall -auto-all
@@ -133,7 +132,7 @@
   other-modules:       Application
                      , Method
   type:                exitcode-stdio-1.0
-  build-depends:       base                      >=4.6   && <4.8
+  build-depends:       base                      >=4.6   && <4.9
                      , mtl                       >=2.1   && <2.3
                      , tasty                     >=0.10  && <0.11
                      , tasty-hunit               >=0.9   && <0.10
diff --git a/src/Control/Monad/Apiary/Action/Internal.hs b/src/Control/Monad/Apiary/Action/Internal.hs
--- a/src/Control/Monad/Apiary/Action/Internal.hs
+++ b/src/Control/Monad/Apiary/Action/Internal.hs
@@ -94,7 +94,12 @@
 
 import qualified System.PosixCompat.Files as Files
 
+#if MIN_VERSION_base(4,8,0)
+import Control.Applicative (Alternative(..))
+#else
+import Data.Monoid(Monoid(..))
 import Control.Applicative (Applicative(..), Alternative(..), (<$>))
+#endif
 import Control.Monad (MonadPlus(..), liftM)
 import Control.Monad.Trans(MonadIO(..), MonadTrans(..))
 import Control.Monad.Base(MonadBase(..), liftBaseDefault)
@@ -111,7 +116,6 @@
 import qualified Network.Wai as Wai
 import qualified Network.Wai.Parse as P
 
-import Data.Monoid(Monoid(..), (<>))
 import qualified Network.Routing.Dict as Dict
 import Data.Apiary.Param(Param, File(..))
 import Data.Apiary.SProxy(SProxy(..))
@@ -178,7 +182,7 @@
 
 instance Monoid ResponseBody where
     mempty = ResponseBuilder mempty
-    ResponseBuilder a `mappend` ResponseBuilder b = ResponseBuilder $ a <> b
+    ResponseBuilder a `mappend` ResponseBuilder b = ResponseBuilder $ a `mappend` b
     _ `mappend` b = b
 
 toResponse :: ActionState -> Wai.Response
@@ -694,7 +698,7 @@
 
 -- | append response body from builder. since 1.2.0.
 appendBuilder :: Monad m => Builder -> ActionT exts prms m ()
-appendBuilder b = modifyState (\s -> s { actionResponse = actionResponse s <> ResponseBuilder b } )
+appendBuilder b = modifyState (\s -> s { actionResponse = actionResponse s `mappend` ResponseBuilder b } )
 
 -- | append response body from strict bytestring. since 1.2.0.
 appendBytes :: Monad m => S.ByteString -> ActionT exts prms m ()
diff --git a/src/Control/Monad/Apiary/Filter.hs b/src/Control/Monad/Apiary/Filter.hs
--- a/src/Control/Monad/Apiary/Filter.hs
+++ b/src/Control/Monad/Apiary/Filter.hs
@@ -43,7 +43,6 @@
 import Network.Wai.Parse (parseContentType, parseHttpAccept)
 import qualified Network.HTTP.Types as HTTP
 
-import Control.Applicative((<$>))
 import Control.Monad(mzero)
 import Control.Monad.Trans(MonadIO)
 
@@ -112,7 +111,7 @@
 -- | filter by 'Control.Monad.Apiary.Action.rootPattern' of 'Control.Monad.Apiary.Action.ApiaryConfig'.
 root :: (Monad m, Monad actM) => Filter' exts actM m
 root = focus DocRoot Nothing $ R.raw "ROOT" $ \d r -> do
-    roots <- rootPattern <$> getConfig
+    roots <- rootPattern `fmap` getConfig
     case r of
         [] -> return (d, [])
         [p] | p `elem` roots -> return (d, [])
@@ -160,7 +159,7 @@
 -- [key|key|] =: pInt
 -- @
 (=:) :: (HasDesc query, MonadIO actM, ReqParam v, KnownSymbol k, k </ prms)
-     => query k -> proxy v -> Filter exts actM m prms (k := v ': prms)
+     => query k -> proxy v -> Filter exts actM m prms (k ':= v ': prms)
 k =: v = query k (pFirst v)
 
 -- | get one matched paramerer. since 0.5.0.0.
@@ -171,7 +170,7 @@
 -- [key|key|] =!: pInt
 -- @
 (=!:) :: (HasDesc query, MonadIO actM, ReqParam v, KnownSymbol k, k </ prms)
-      => query k -> proxy v -> Filter exts actM m prms (k := v ': prms)
+      => query k -> proxy v -> Filter exts actM m prms (k ':= v ': prms)
 k =!: t = query k (pOne t)
 
 -- | get optional first paramerer. since 0.5.0.0.
@@ -182,7 +181,7 @@
 -- [key|key|] =?: pInt
 -- @
 (=?:) :: (HasDesc query, MonadIO actM, ReqParam v, KnownSymbol k, k </ prms)
-      => query k -> proxy v -> Filter exts actM m prms (k := Maybe v ': prms)
+      => query k -> proxy v -> Filter exts actM m prms (k ':= Maybe v ': prms)
 k =?: t = query k (pOption t)
 
 -- | get optional first paramerer with default. since 0.16.0.
@@ -193,7 +192,7 @@
 -- [key|key|] =!?: (0 :: Int)
 -- @
 (=?!:) :: forall query k v exts prms actM m. (HasDesc query, MonadIO actM, Show v, ReqParam v, KnownSymbol k, k </ prms)
-       => query k -> v -> Filter exts actM m prms (k := v ': prms)
+       => query k -> v -> Filter exts actM m prms (k ':= v ': prms)
 k =?!: v = query k (pOptional v)
 
 -- | get many paramerer. since 0.5.0.0.
@@ -202,7 +201,7 @@
 -- [key|key|] =*: pInt
 -- @
 (=*:) :: (HasDesc query, MonadIO actM, ReqParam v, KnownSymbol k, k </ prms)
-      => query k -> proxy v -> Filter exts actM m prms (k := [v] ': prms)
+      => query k -> proxy v -> Filter exts actM m prms (k ':= [v] ': prms)
 k =*: t = query k (pMany t)
 
 -- | get some paramerer. since 0.5.0.0.
@@ -211,12 +210,12 @@
 -- [key|key|] =+: pInt
 -- @
 (=+:) :: (HasDesc query, MonadIO actM, ReqParam v, KnownSymbol k, k </ prms)
-      => query k -> proxy v -> Filter exts actM m prms (k := [v] ': prms)
+      => query k -> proxy v -> Filter exts actM m prms (k ':= [v] ': prms)
 k =+: t = query k (pSome t)
 
 -- | get existance of key only query parameter. since v0.17.0.
 switchQuery :: (HasDesc proxy, MonadIO actM, KnownSymbol k, k </ prms)
-            => proxy k -> Filter exts actM m prms (k := Bool ': prms)
+            => proxy k -> Filter exts actM m prms (k ':= Bool ': prms)
 switchQuery k = focus doc Nothing $ R.raw "switch" $ \d t -> do
     qs      <- getQueryParams
     (ps,fs) <- getRequestBody
@@ -229,7 +228,7 @@
 
 -- | filter by header and get first. since 0.6.0.0.
 header :: (KnownSymbol k, Monad actM, k </ prms)
-       => proxy k -> Filter exts actM m prms (k := SC.ByteString ': prms)
+       => proxy k -> Filter exts actM m prms (k ':= SC.ByteString ': prms)
 header k = focus doc Nothing $ R.raw "header" $ \d t -> do
     n <- maybe mzero return . lookup (CI.mk . SC.pack $ symbolVal k) . Wai.requestHeaders =<< getRequest
     return (Dict.add k n d, t)
@@ -248,7 +247,7 @@
 -- | require Accept header and set response Content-Type. since 0.16.0.
 accept :: Monad actM => ContentType -> Filter' exts actM m
 accept ect = focus (DocAccept ect) Nothing $ R.raw "accept" $ \d t ->
-    (lookup "Accept" . Wai.requestHeaders <$> getRequest) >>= \case
+    fmap (lookup "Accept" . Wai.requestHeaders) getRequest >>= \case
         Nothing -> mzero
         Just ac ->
             let ex@(et, _) = parseContentType ect
diff --git a/src/Control/Monad/Apiary/Filter/Capture.hs b/src/Control/Monad/Apiary/Filter/Capture.hs
--- a/src/Control/Monad/Apiary/Filter/Capture.hs
+++ b/src/Control/Monad/Apiary/Filter/Capture.hs
@@ -31,12 +31,12 @@
 
 -- | get first path and drill down. since 0.11.0.
 fetch' :: (k Dict.</ prms, KnownSymbol k, Path p, Monad actM) => proxy k -> proxy' p -> Maybe Html
-       -> Filter exts actM m prms (k := p ': prms)
+       -> Filter exts actM m prms (k ':= p ': prms)
 fetch' k p h = focus (DocFetch (T.pack $ symbolVal k) (pathRep p) h) Nothing $ R.fetch k (readPathAs p)
 
 fetch :: forall proxy k p exts prms actM m. (k Dict.</ prms, KnownSymbol k, Path p, Monad actM)
-      => proxy (k := p) -> Maybe Html
-      -> Filter exts actM m prms (k := p ': prms)
+      => proxy (k ':= p) -> Maybe Html
+      -> Filter exts actM m prms (k ':= p ': prms)
 fetch _ h = fetch' k p h
   where
     k = Proxy :: Proxy k
@@ -47,5 +47,5 @@
 
 restPath :: (k Dict.</ prms, KnownSymbol k, Monad m, Monad actM)
          => proxy k -> Maybe Html
-         -> Filter exts actM m prms (k := [T.Text] ': prms)
+         -> Filter exts actM m prms (k ':= [T.Text] ': prms)
 restPath k h = focus (DocRest (T.pack $ symbolVal k) h) Nothing (R.rest k)
diff --git a/src/Control/Monad/Apiary/Filter/Internal.hs b/src/Control/Monad/Apiary/Filter/Internal.hs
--- a/src/Control/Monad/Apiary/Filter/Internal.hs
+++ b/src/Control/Monad/Apiary/Filter/Internal.hs
@@ -34,7 +34,7 @@
 
 -- | filter and append argument.
 function' :: (KnownSymbol key, Monad actM, key </ prms) => (Doc -> Doc) -> (Wai.Request -> Maybe (proxy key, prm))
-          -> Filter exts actM m prms (key := prm ': prms)
+          -> Filter exts actM m prms (key ':= prm ': prms)
 function' d f = function d $ \c r -> f r >>= \(k, p) -> return $ Dict.add k p c
 
 -- | filter only(not modify arguments).
diff --git a/src/Control/Monad/Apiary/Filter/Internal/Capture/TH.hs b/src/Control/Monad/Apiary/Filter/Internal/Capture/TH.hs
--- a/src/Control/Monad/Apiary/Filter/Internal/Capture/TH.hs
+++ b/src/Control/Monad/Apiary/Filter/Internal/Capture/TH.hs
@@ -6,7 +6,6 @@
 module Control.Monad.Apiary.Filter.Internal.Capture.TH(capture) where
 
 import Control.Arrow(first)
-import Control.Applicative((<$>))
 
 import qualified Language.Haskell.TH as TH
 import Language.Haskell.TH.Quote(QuasiQuoter(..))
@@ -29,9 +28,9 @@
 splitPath = map T.unpack . T.splitOn "/" . T.pack
 
 description :: String -> TH.Q (String, TH.ExpQ)
-description s = case break (`elem` "([") s of
+description s = case break (`elem` ("([" :: String)) s of
     (t, []) -> return (t, [|Nothing|])
-    (t, st) -> case break (`elem` ")]") st of
+    (t, st) -> case break (`elem` (")]" :: String)) st of
         (_:'$':b, ")") -> do
             TH.reportWarning "DEPRECATED () description. use []."
             v <- TH.lookupValueName b
@@ -51,8 +50,8 @@
     (k, d) <- description tS
     [|Capture.restPath (SProxy :: SProxy $(TH.litT $ TH.strTyLit k)) $d . $(mkCap as) |]
 mkCap (str:as)
-    | "::" `isInfixOf` fst (break (`elem` "([") str) = do
-        (key, d) <- first T.pack <$> description str
+    | "::" `isInfixOf` fst (break (`elem` ("([" :: String)) str) = do
+        (key, d) <- first T.pack `fmap` description str
         let v = T.unpack . T.strip . fst $ T.breakOn    "::" key
             t = T.unpack . T.strip . snd $ T.breakOnEnd "::" key
         ty <- TH.lookupTypeName t >>= maybe (fail $ t ++ " not found.") return
diff --git a/src/Control/Monad/Apiary/Internal.hs b/src/Control/Monad/Apiary/Internal.hs
--- a/src/Control/Monad/Apiary/Internal.hs
+++ b/src/Control/Monad/Apiary/Internal.hs
@@ -35,7 +35,10 @@
 
 import qualified Network.Wai as Wai
 
+#if !MIN_VERSION_base(4,8,0)
+import Data.Monoid(Monoid(..))
 import Control.Applicative(Applicative(..), (<$>))
+#endif
 import Control.Monad(liftM)
 import Control.Monad.Trans(MonadIO(liftIO), MonadTrans(lift))
 import Control.Monad.Trans.Control
@@ -54,7 +57,6 @@
 import Data.Apiary.Extension ( Has, MonadExts(..), getExt, noExtension )
 import Data.Apiary.Extension.Internal(Initializer(..), allMiddleware, allMiddleware')
 import Data.Apiary.Document.Internal(Doc(..), docsToDocuments)
-import Data.Monoid(Monoid(..), (<>))
 
 import Text.Blaze.Html(Html)
 import qualified Data.Text as T
@@ -150,7 +152,7 @@
     mf <*> ma = ApiaryT $ \env cont ->
         unApiaryT mf env $ \f hdr  ->
         unApiaryT ma env $ \a hdr' ->
-        let hdr'' = hdr <> hdr'
+        let hdr'' = hdr `mappend` hdr'
         in hdr'' `seq` cont (f a) hdr''
 
 instance Monad actM => Monad (ApiaryT exts prms actM m) where
@@ -158,7 +160,7 @@
     m >>= k = ApiaryT $ \env cont ->
         unApiaryT    m  env $ \a hdr  ->
         unApiaryT (k a) env $ \b hdr' -> 
-        let hdr'' = hdr <> hdr'
+        let hdr'' = hdr `mappend` hdr'
         in hdr'' `seq` cont b hdr''
 
 instance Monad actM => MonadTrans (ApiaryT exts prms actM) where
diff --git a/src/Data/Apiary/Document/Internal.hs b/src/Data/Apiary/Document/Internal.hs
--- a/src/Data/Apiary/Document/Internal.hs
+++ b/src/Data/Apiary/Document/Internal.hs
@@ -12,8 +12,6 @@
     , docsToDocuments
     ) where
 
-import Control.Applicative((<$>))
-
 import Data.Typeable(TypeRep)
 import Data.Maybe(mapMaybe)
 import Data.List(groupBy)
@@ -100,9 +98,9 @@
 
 docToDocument :: Doc -> Maybe (Maybe T.Text, PathDoc)
 docToDocument = \case
-    (DocGroup "" d') -> (Nothing,) <$> loop initialToDocumentState d'
-    (DocGroup g  d') -> (Just  g,) <$> loop initialToDocumentState d'
-    d'               -> (Nothing,) <$> loop initialToDocumentState d'
+    (DocGroup "" d') -> (Nothing,) `fmap` loop initialToDocumentState d'
+    (DocGroup g  d') -> (Just  g,) `fmap` loop initialToDocumentState d'
+    d'               -> (Nothing,) `fmap` loop initialToDocumentState d'
   where
     loop st (DocDropNext       d) = loop st (dropNext d)
     loop st (DocPath         p d) = loop st { toDocumentPath = toDocumentPath st . Path p } d
diff --git a/src/Data/Apiary/Extension/Internal.hs b/src/Data/Apiary/Extension/Internal.hs
--- a/src/Data/Apiary/Extension/Internal.hs
+++ b/src/Data/Apiary/Extension/Internal.hs
@@ -7,6 +7,10 @@
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE CPP #-}
 
+#if __GLASGOW_HASKELL__ < 710
+{-# LANGUAGE OverlappingInstances #-}
+#endif
+
 module Data.Apiary.Extension.Internal
     ( Initializer(..)
     , Has(..)
@@ -28,7 +32,11 @@
 instance Has a (a ': as) where
     getExtension _ (AddExtension a _) = a
 
+#if __GLASGOW_HASKELL__ >= 710
+instance {-# OVERLAPPABLE #-} Has a as => Has a (a' ': as) where
+#else
 instance Has a as => Has a (a' ': as) where
+#endif
     getExtension p (AddExtension _ as) = getExtension p as
 
 newtype Initializer m i o = Initializer 
diff --git a/src/Data/Apiary/Param.hs b/src/Data/Apiary/Param.hs
--- a/src/Data/Apiary/Param.hs
+++ b/src/Data/Apiary/Param.hs
@@ -7,6 +7,7 @@
 {-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE CPP #-}
 
 module Data.Apiary.Param
     ( -- * route path parameter
@@ -55,7 +56,11 @@
 import qualified Network.HTTP.Types as HTTP
 
 import Data.Int(Int8, Int16, Int32, Int64)
+#if MIN_VERSION_base(4,8,0)
+import Data.Word(Word8, Word16, Word32, Word64)
+#else
 import Data.Word(Word, Word8, Word16, Word32, Word64)
+#endif
 import Data.Maybe(isJust, catMaybes)
 import Network.Routing.Dict(KV((:=)), type (</), Store)
 import qualified Network.Routing.Dict as Dict
@@ -338,34 +343,34 @@
 
 data First a = First
 instance Strategy First where
-    type SNext First k a ps = k := a ': ps
+    type SNext First k a ps = k ':= a ': ps
     strategy _ k (Just a:_) d = return $ Dict.add k a d
     strategy _ _ _          _ = mzero
     strategyRep _ = StrategyRep "first"
 
 data One a = One
 instance Strategy One where
-    type SNext One k a ps = k := a ': ps
+    type SNext One k a ps = k ':= a ': ps
     strategy _ k [Just a] d = return $ Dict.add k a d
     strategy _ _ _        _ = mzero
     strategyRep _ = StrategyRep "one"
 
 data Many a = Many
 instance Strategy Many where
-    type SNext Many k a ps = k := [a] ': ps
+    type SNext Many k a ps = k ':= [a] ': ps
     strategy _ k as d = if all isJust as then return $ Dict.add k (catMaybes as) d else mzero
     strategyRep _ = StrategyRep "many"
 
 data Some a = Some
 instance Strategy Some where
-    type SNext Some k a ps = k := [a] ': ps
+    type SNext Some k a ps = k ':= [a] ': ps
     strategy _ _ [] _ = mzero
     strategy _ k as d = if all isJust as then return $ Dict.add k (catMaybes as) d else mzero
     strategyRep _ = StrategyRep "some"
 
 data Option a = Option
 instance Strategy Option where
-    type SNext Option k a ps = k := Maybe a ': ps
+    type SNext Option k a ps = k ':= Maybe a ': ps
     strategy _ k (Just a:_)  d = return $ Dict.add k (Just a) d
     strategy _ _ (Nothing:_) _ = mzero
     strategy _ k []          d = return $ Dict.add k Nothing d
@@ -373,7 +378,7 @@
 
 data Optional a = Optional T.Text a
 instance Strategy Optional where
-    type SNext Optional k a ps = k := a ': ps
+    type SNext Optional k a ps = k ':= a ': ps
     strategy _              k (Just a:_)  d = return $ Dict.add k a d
     strategy _              _ (Nothing:_) _ = mzero
     strategy (Optional _ a) k []          d = return $ Dict.add k a d
diff --git a/src/Web/Apiary/Heroku.hs b/src/Web/Apiary/Heroku.hs
--- a/src/Web/Apiary/Heroku.hs
+++ b/src/Web/Apiary/Heroku.hs
@@ -4,6 +4,7 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE Rank2Types #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE CPP #-}
 
 module Web.Apiary.Heroku
     ( Heroku
@@ -25,7 +26,9 @@
 
 import Control.Exception(catch, try, SomeException)
 import Control.Arrow(second)
+#if !MIN_VERSION_base(4,8,0)
 import Control.Applicative((<$>), (<$), Applicative(..))
+#endif
 import Control.Monad.Trans(MonadIO(..))
 
 import Data.IORef(IORef, newIORef, readIORef, writeIORef)
diff --git a/tests/Application.hs b/tests/Application.hs
--- a/tests/Application.hs
+++ b/tests/Application.hs
@@ -1,7 +1,9 @@
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE QuasiQuotes #-}
-{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
 {-# LANGUAGE DataKinds #-}
+
+{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
 
 module Application(test) where