diff --git a/mu-rpc.cabal b/mu-rpc.cabal
--- a/mu-rpc.cabal
+++ b/mu-rpc.cabal
@@ -1,5 +1,5 @@
 name:               mu-rpc
-version:            0.4.0.0
+version:            0.4.0.1
 synopsis:           Protocol-independent declaration of services and servers.
 description:
   Protocol-independent declaration of services and servers for mu-haskell.
@@ -35,7 +35,7 @@
     , mtl               >=2.2   && <2.3
     , mu-schema         ==0.3.*
     , sop-core          >=0.5   && <0.6
-    , template-haskell  >=2.14  && <2.16
+    , template-haskell  >=2.14  && <2.17
     , text              >=1.2   && <1.3
     , wai               >=3.2   && <4
 
diff --git a/src/Mu/Rpc/Examples.hs b/src/Mu/Rpc/Examples.hs
--- a/src/Mu/Rpc/Examples.hs
+++ b/src/Mu/Rpc/Examples.hs
@@ -21,14 +21,14 @@
 -}
 module Mu.Rpc.Examples where
 
-import qualified Data.Aeson as J
+import qualified Data.Aeson               as J
 import           Data.Conduit
 import           Data.Conduit.Combinators as C
 import qualified Data.Text                as T
 import           GHC.Generics
 import           GHC.TypeLits
 
-import           Mu.Adapter.Json ()
+import           Mu.Adapter.Json          ()
 import           Mu.Rpc
 import           Mu.Schema
 import           Mu.Server
@@ -46,17 +46,17 @@
      ]
 
 type QuickStartService
-  = 'Package ('Just "helloworld")
+  = ('Package ('Just "helloworld")
       '[ 'Service "Greeter"
         '[ 'Method "SayHello"
-          '[ 'ArgSingle ('Nothing @Symbol) ('SchemaRef QuickstartSchema "HelloRequest") ]
+          '[ 'ArgSingle ('Nothing :: Maybe Symbol) ('SchemaRef QuickstartSchema "HelloRequest") ]
             ('RetSingle ('SchemaRef QuickstartSchema "HelloResponse"))
         , 'Method "SayHi"
-          '[ 'ArgSingle ('Nothing @Symbol) ('SchemaRef QuickstartSchema "HiRequest")]
+          '[ 'ArgSingle ('Nothing :: Maybe Symbol) ('SchemaRef QuickstartSchema "HiRequest")]
             ('RetStream ('SchemaRef QuickstartSchema "HelloResponse"))
         , 'Method "SayManyHellos"
-          '[ 'ArgStream ('Nothing @Symbol) ('SchemaRef QuickstartSchema "HelloRequest")]
-                ('RetStream ('SchemaRef QuickstartSchema "HelloResponse")) ] ] :: Package'
+          '[ 'ArgStream ('Nothing :: Maybe Symbol) ('SchemaRef QuickstartSchema "HelloRequest")]
+                ('RetStream ('SchemaRef QuickstartSchema "HelloResponse")) ] ] :: Package')
 
 newtype HelloRequest = HelloRequest { name :: T.Text }
   deriving ( Show, Eq, Generic
diff --git a/src/Mu/Server.hs b/src/Mu/Server.hs
--- a/src/Mu/Server.hs
+++ b/src/Mu/Server.hs
@@ -1,3 +1,4 @@
+{-# language CPP                       #-}
 {-# language ConstraintKinds           #-}
 {-# language DataKinds                 #-}
 {-# language ExistentialQuantification #-}
@@ -78,6 +79,10 @@
 import           Mu.Rpc
 import           Mu.Schema
 
+#if __GLASGOW_HASKELL__ < 880
+import Unsafe.Coerce (unsafeCoerce)
+#endif
+
 -- | Constraint for monads that can be used as servers
 type MonadServer m = (MonadError ServerError m, MonadIO m)
 -- | Simplest monad which satisfies 'MonadServer'.
@@ -434,7 +439,11 @@
                  -> ServicesT chn info ss m hs
     wrapServices S0 = S0
     wrapServices (h :<&>: rest)
+#if __GLASGOW_HASKELL__ >= 880
       = wrapHandlers h :<&>: wrapServices rest
+#else
+      = unsafeCoerce (wrapHandlers (unsafeCoerce h)) :<&>: unsafeCoerce (wrapServices rest)
+#endif
 
     wrapHandlers :: forall inh ms innerHs.
                     HandlersT chn info inh ms m innerHs