diff --git a/pusher-http-haskell.cabal b/pusher-http-haskell.cabal
--- a/pusher-http-haskell.cabal
+++ b/pusher-http-haskell.cabal
@@ -1,5 +1,5 @@
 name: pusher-http-haskell
-version: 1.5.1.11
+version: 1.5.1.12
 cabal-version: 1.18
 build-type: Simple
 license: MIT
@@ -22,7 +22,7 @@
 library
 
     if impl(ghc >=8.0.0)
-        ghc-options: -Wcompat -Whi-shadowing -Wmissing-signatures
+        ghc-options: -Wcompat -Wmissing-signatures
     else
         ghc-options: -fwarn-hi-shadowing -fwarn-missing-signatures -fwarn-tabs
     exposed-modules:
@@ -32,8 +32,8 @@
         Network.Pusher.Internal.HTTP
         Network.Pusher.Protocol
     build-depends:
-        aeson >=0.8 && <1.5,
-        base >=4.7 && <4.14,
+        aeson >=0.8 && <1.6,
+        base >=4.7 && <4.15,
         bytestring ==0.10.*,
         base16-bytestring ==0.1.*,
         cryptonite >= 0.6 && <0.27,
@@ -42,7 +42,7 @@
         http-types >=0.8 && <0.13,
         memory >= 0.7 && <0.16,
         text ==1.2.*,
-        time >=1.5 && <1.10,
+        time >=1.5 && <1.11,
         transformers >=0.4 && <0.6,
         unordered-containers ==0.2.*,
         vector >=0.10 && <0.13
@@ -59,7 +59,7 @@
 test-suite tests
 
     if impl(ghc >=8.0.0)
-        ghc-options: -Wcompat -Whi-shadowing -Wmissing-signatures
+        ghc-options: -Wcompat -Wmissing-signatures
     else
         ghc-options: -fwarn-hi-shadowing -fwarn-missing-signatures -fwarn-tabs
     type: exitcode-stdio-1.0
diff --git a/src/Network/Pusher/Data.hs b/src/Network/Pusher/Data.hs
--- a/src/Network/Pusher/Data.hs
+++ b/src/Network/Pusher/Data.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE DeriveGeneric #-}
 
 {-|
@@ -59,7 +60,9 @@
 import qualified Data.HashSet as HS
 import Data.Hashable (Hashable)
 import Data.Maybe (fromMaybe)
+#if !(MIN_VERSION_base(4,11,0))
 import Data.Monoid ((<>))
+#endif
 import qualified Data.Text as T
 import Data.Text.Encoding (encodeUtf8)
 import qualified Data.Vector as V
diff --git a/src/Network/Pusher/Internal.hs b/src/Network/Pusher/Internal.hs
--- a/src/Network/Pusher/Internal.hs
+++ b/src/Network/Pusher/Internal.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 {-|
 Module      : Network.Pusher.Internal
 Description : Pure functions called by the public interface
@@ -19,7 +21,9 @@
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as BL
 import Data.Maybe (maybeToList)
+#if !(MIN_VERSION_base(4,11,0))
 import Data.Monoid ((<>))
+#endif
 import qualified Data.Text as T
 import Data.Text.Encoding (encodeUtf8)
 
diff --git a/src/Network/Pusher/Internal/Auth.hs b/src/Network/Pusher/Internal/Auth.hs
--- a/src/Network/Pusher/Internal/Auth.hs
+++ b/src/Network/Pusher/Internal/Auth.hs
@@ -24,7 +24,9 @@
 
 import qualified Data.Aeson as A
 import Data.Char (toLower)
+#if !(MIN_VERSION_base(4,11,0))
 import Data.Monoid ((<>))
+#endif
 import Data.Text.Encoding (encodeUtf8)
 import GHC.Exts (sortWith)
 #if MIN_VERSION_aeson(1,0,0)
diff --git a/src/Network/Pusher/Internal/HTTP.hs b/src/Network/Pusher/Internal/HTTP.hs
--- a/src/Network/Pusher/Internal/HTTP.hs
+++ b/src/Network/Pusher/Internal/HTTP.hs
@@ -29,7 +29,9 @@
 import qualified Data.Aeson as A
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as BL
+#if !(MIN_VERSION_base(4,11,0))
 import Data.Monoid ((<>))
+#endif
 import qualified Data.Text as T
 import Data.Text.Encoding (decodeUtf8')
 import qualified Network.HTTP.Client as HTTP.Client
diff --git a/test/Push.hs b/test/Push.hs
--- a/test/Push.hs
+++ b/test/Push.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Push where
 
 import Data.Aeson ((.=))
@@ -6,7 +8,9 @@
 import qualified Data.ByteString.Lazy.Char8 as B
 import qualified Data.HashMap.Strict as HM
 import Data.Maybe (fromJust)
+#if !(MIN_VERSION_base(4,11,0))
 import Data.Monoid ((<>))
+#endif
 import Data.Scientific
 import qualified Data.Text as T
 import qualified Data.Vector as V
@@ -62,15 +66,17 @@
 validFCMDecoding :: (B.ByteString, Notification)
 validFCMDecoding =
   let bs =
-        "{\
-          \ \"interests\": [\"interestOne\"]\
-          \ ,\"fcm\": {\
-          \     \"notification\":\
-          \        {\"title\":\"titleText\"\
-          \        ,\"body\":\"bodyText\"\
-          \        }\
-          \  }\
-          \}"
+        B.unlines
+          [ "{"
+          , "  \"interests\": [\"interestOne\"],"
+          , "  \"fcm\": {"
+          , "    \"notification\": {"
+          , "      \"title\": \"titleText\","
+          , "      \"body\": \"bodyText\""
+          , "    }"
+          , "  }"
+          , "}"
+          ]
       notification =
         Notification
         { notificationInterest = fromJust . mkInterest $ "interestOne"
@@ -122,22 +128,17 @@
     let apns = APNSPayload payload
         bs :: ByteString
         bs =
-          "{\
-          \  \"aps\":\
-          \   {\
-          \     \"alert\":\
-          \       {\"title\":\"" <>
-          (B.pack . T.unpack $ titleText) <>
-          "\"\
-          \       ,\"body\":\"" <>
-          (B.pack . T.unpack $ bodyText) <>
-          "\"\
-          \       }\
-          \   }\
-          \   ,\"data\":" <>
-          (A.encode dataJSON) <>
-          "\
-          \}"
+          B.unlines
+            [ "{"
+            , "  \"aps\": {"
+            , "    \"alert\": {"
+            , "       \"title\": \"" <> (B.pack . T.unpack $ titleText) <> "\","
+            , "       \"body\": \"" <> (B.pack . T.unpack $ bodyText) <> "\""
+            , "    }"
+            , "  },"
+            , "  \"data\": " <> (A.encode dataJSON)
+            , "}"
+            ]
     return $ APNSDecoding (bs, Just apns)
 
 instance Arbitrary GCMDecoding where
@@ -153,19 +154,15 @@
         gcm = GCMPayload payload
         bs :: ByteString
         bs =
-          "{\
-          \  \"notification\":\
-          \    {\"title\":\"" <>
-          (B.pack . T.unpack $ titleText) <>
-          "\"\
-          \    ,\"body\":\"" <>
-          (B.pack . T.unpack $ bodyText) <>
-          "\"\
-          \    }\
-          \    ,\"data\":" <>
-          (A.encode dataJSON) <>
-          "\
-          \}"
+          B.unlines
+            [ "{"
+            , "  \"notification\": {"
+            , "    \"title\": \"" <> (B.pack . T.unpack $ titleText) <> "\","
+            , "    \"body\": \"" <> (B.pack . T.unpack $ bodyText) <> "\""
+            , "  },"
+            , "  \"data\": " <> (A.encode dataJSON)
+            , "}"
+            ]
     return $ GCMDecoding (bs, Just gcm)
 
 instance Arbitrary FCMDecoding where
@@ -181,19 +178,15 @@
         gcm = FCMPayload payload
         bs :: ByteString
         bs =
-          "{\
-          \  \"notification\":\
-          \    {\"title\":\"" <>
-          (B.pack . T.unpack $ titleText) <>
-          "\"\
-          \    ,\"body\":\"" <>
-          (B.pack . T.unpack $ bodyText) <>
-          "\"\
-          \    }\
-          \    ,\"data\":" <>
-          (A.encode dataJSON) <>
-          "\
-          \}"
+          B.unlines
+            [ "{"
+            , "  \"notification\": {"
+            , "    \"title\": \"" <> (B.pack . T.unpack $ titleText) <> "\","
+            , "    \"body\": \"" <> (B.pack . T.unpack $ bodyText) <> "\""
+            , "  },"
+            , "  \"data\": " <> (A.encode dataJSON)
+            , "}"
+            ]
     return $ FCMDecoding (bs, Just gcm)
 
 instance Arbitrary NotificationDecoding where