diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,8 @@
+0.3.0.1
+=======
+
+- Tighten compile flags and fix some errors
+
 0.3.0.0
 =======
 
diff --git a/push-notify-apn.cabal b/push-notify-apn.cabal
--- a/push-notify-apn.cabal
+++ b/push-notify-apn.cabal
@@ -1,5 +1,5 @@
 name:                push-notify-apn
-version:             0.3.0.0
+version:             0.3.0.1
 synopsis:            Send push notifications to mobile iOS devices
 description:
     push-notify-apn is a library and command line utility that can be used to send
@@ -42,6 +42,12 @@
                      , x509
                      , x509-store
                      , x509-system
+
+  ghc-options:
+    -Wall -W -fwarn-unused-imports -fwarn-unused-binds -fwarn-orphans
+    -fwarn-unused-matches -fwarn-unused-do-bind -fwarn-wrong-do-bind
+    -fwarn-missing-signatures -fno-warn-partial-type-signatures
+    -Wredundant-constraints
 
   default-language:    Haskell2010
 
diff --git a/src/Network/PushNotify/APN.hs b/src/Network/PushNotify/APN.hs
--- a/src/Network/PushNotify/APN.hs
+++ b/src/Network/PushNotify/APN.hs
@@ -51,7 +51,6 @@
     ) where
 
 import           Control.Concurrent
-import           Control.Concurrent.QSem
 import           Control.Exception.Lifted (Exception, try, bracket_, throw, throwIO)
 import           Control.Monad
 import           Control.Monad.Except
@@ -61,29 +60,22 @@
 import           Data.Char                            (toLower)
 import           Data.Default                         (def)
 import           Data.Either
-import           Data.Int
 import           Data.IORef
 import           Data.Map.Strict                      (Map)
 import           Data.Maybe
 import           Data.Pool
-import           Data.Semigroup                       ((<>))
 import           Data.Text                            (Text)
 import           Data.Time.Clock
-import           Data.Time.Clock.POSIX
 import           Data.Typeable                        (Typeable)
-import           Data.X509
 import           Data.X509.CertificateStore
 import           GHC.Generics
 import           Network.HTTP2.Frame                  (ErrorCodeId,
                                                        toErrorCodeId)
 import "http2-client" Network.HTTP2.Client
-import "http2-client" Network.HTTP2.Client.FrameConnection
 import "http2-client" Network.HTTP2.Client.Helpers
 import           Network.TLS                          hiding (sendData)
 import           Network.TLS.Extra.Cipher
 import           System.IO.Error
-import           System.Mem.Weak
-import           System.Random
 import           System.Timeout (timeout)
 import           System.X509
 
@@ -125,9 +117,6 @@
 -- | An APN token used to uniquely identify a device
 newtype ApnToken = ApnToken { unApnToken :: ByteString }
 
-class SpecifyError a where
-    isAnError :: IOError -> a
-
 -- | Create a token from a raw bytestring
 rawToken
     :: ByteString
@@ -473,10 +462,16 @@
     True -> pure False
     False -> do
       castore <- maybe (pure Nothing) readCertificateStore $ aciCaPath aci
-      credential <- case (aciCertPath aci, aciCertKey aci) of
+      credential <- loadCredentials aci
+      return $ isJust castore && isRight credential
+
+loadCredentials :: ApnConnectionInfo -> IO (Either String Credential)
+loadCredentials aci =
+    case (aciCertPath aci, aciCertKey aci) of
         (Just cert, Just key) -> credentialLoadX509 cert key
+        (Just _, Nothing) -> pure $ Left "no cert"
+        (Nothing, Just _) -> pure $ Left "no key"
         (Nothing, Nothing) -> pure $ Left "no creds"
-      return $ isJust castore && isRight credential
 
 newConnection :: ApnConnectionInfo -> IO ApnConnection
 newConnection aci = do
@@ -492,8 +487,7 @@
     clip <- case (aciUseJWT aci) of
         True -> do
           castore <- getSystemCertificateStore
-          let maxConcurrentStreams = aciMaxConcurrentStreams aci
-              clip = ClientParams
+          let clip = ClientParams
                   { clientUseMaxFragmentLength=Nothing
                   , clientServerIdentification=(T.unpack hostname, undefined)
                   , clientUseServerNameIndication=True
@@ -511,9 +505,7 @@
           pure clip
         False -> do
           Just castore <- maybe (pure Nothing) readCertificateStore $ aciCaPath aci
-          Right credential <- case (aciCertPath aci, aciCertKey aci) of
-            (Just cert, Just key) -> credentialLoadX509 cert key
-            (Nothing, Nothing) -> pure $ Left "no creds"
+          Right credential <- loadCredentials aci
           let credentials = Credentials [credential]
               shared      = def { sharedCredentials = credentials
                                 , sharedCAStore=castore }
@@ -535,7 +527,7 @@
           pure clip
 
     isOpen <- newIORef True
-    let handleGoAway rsgaf = do
+    let handleGoAway _rsgaf = do
             lift $ writeIORef isOpen False
             return ()
     client <-
@@ -546,7 +538,7 @@
         linkAsyncs client
         return client
     flowWorker <- forkIO $ forever $ do
-        updated <- runClientIO $ _updateWindow $ _incomingFlowControl client
+        _updated <- runClientIO $ _updateWindow $ _incomingFlowControl client
         threadDelay 1000000
     workersem <- newQSem maxConcurrentStreams
     return $ ApnConnection client aci workersem flowWorker isOpen
@@ -645,7 +637,7 @@
             handler isfc osfc = do
                 -- sendData client stream (HTTP2.setEndStream) message
                 upload message (HTTP2.setEndHeader . HTTP2.setEndStream) client (_outgoingFlowControl client) stream osfc
-                let pph hStreamId hStream hHeaders hIfc hOfc =
+                let pph _hStreamId _hStream hHeaders _hIfc _hOfc =
                         lift $ print hHeaders
                 response <- waitStream stream isfc pph
                 let (errOrHeaders, frameResponses, _) = response
@@ -666,6 +658,9 @@
                             "429" -> decodeReason ApnMessageResultTemporaryError body
                             "500" -> decodeReason ApnMessageResultTemporaryError body
                             "503" -> decodeReason ApnMessageResultTemporaryError body
+                            unknown ->
+                                ApnMessageResultFatalError $
+                                ApnFatalErrorOther (T.pack $ "unhandled status: " ++ show unknown)
         in StreamDefinition init handler
     case res of
         Left _     -> return ApnMessageResultBackoff -- Too much concurrency