diff --git a/keid-sound-openal.cabal b/keid-sound-openal.cabal
--- a/keid-sound-openal.cabal
+++ b/keid-sound-openal.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           keid-sound-openal
-version:        0.1.1.0
+version:        0.2.0.0
 synopsis:       OpenAL sound system for Keid engine.
 category:       Game Engine
 author:         IC Rainbow
@@ -90,9 +90,9 @@
       ViewPatterns
   ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wpartial-fields -Wredundant-constraints
   build-depends:
-      OpenAL
-    , base >=4.7 && <5
+      base >=4.7 && <5
     , keid-core >=0.1.2.0
+    , openal-ffi >=0.0.1
     , opusfile >=0.1.0.1
     , resourcet
     , rio >=0.1.12.0
diff --git a/src/Engine/Sound/Device.hs b/src/Engine/Sound/Device.hs
--- a/src/Engine/Sound/Device.hs
+++ b/src/Engine/Sound/Device.hs
@@ -1,5 +1,5 @@
 module Engine.Sound.Device
-  ( OpenAL.Device
+  ( ALC.Device
   , allocate
   , create
   , destroy
@@ -7,7 +7,8 @@
 
 import RIO
 
-import Sound.OpenAL qualified as OpenAL
+import Foreign (nullPtr)
+import Sound.OpenAL.FFI.ALC qualified as ALC
 import UnliftIO.Resource qualified as Resource
 
 allocate
@@ -16,7 +17,7 @@
      , MonadReader env m
      , HasLogFunc env
      )
-  => m (Resource.ReleaseKey, OpenAL.Device)
+  => m (Resource.ReleaseKey, ALC.Device)
 allocate = do
   soundDevice <- create
   soundDeviceDestroy <- toIO $ destroy soundDevice
@@ -28,28 +29,24 @@
      , HasLogFunc env
      , MonadUnliftIO m
      )
-  => m OpenAL.Device
+  => m ALC.Device
 create = do
-  OpenAL.openDevice Nothing >>= \case
-    Nothing -> do
-      logError "OpenAL: no devices"
-      exitFailure
-    Just device -> do
-      OpenAL.createContext device [] >>= \case
-        Nothing -> do
-          logError "OpenAL.createContext failed"
-          exitFailure
-        Just ctx -> do
-          OpenAL.currentContext OpenAL.$=! Just ctx
-          pure device
+  device <- liftIO $ ALC.alcOpenDevice nullPtr
+  context <- liftIO $ ALC.alcCreateContext device nullPtr
 
+  ok <- liftIO $ ALC.alcMakeContextCurrent context
+  if ok == 1 then
+    pure device
+  else do
+    logError "OpenAL: alcMakeContextCurrent failed"
+    exitFailure
+
 destroy
   :: (MonadIO m, MonadReader env m, HasLogFunc env)
-  => OpenAL.Device
+  => ALC.Device
   -> m ()
-destroy device =
-  OpenAL.closeDevice device >>= \case
-    True ->
-      pure ()
-    False ->
-      logWarn "OpenAL: closeDevice error"
+destroy device = do
+  -- ALC.alcDestroyContext context
+  ok <- liftIO $ ALC.alcCloseDevice device
+  unless (ok == 1) $
+    logWarn "OpenAL: closeDevice error"
diff --git a/src/Engine/Sound/Source.hs b/src/Engine/Sound/Source.hs
--- a/src/Engine/Sound/Source.hs
+++ b/src/Engine/Sound/Source.hs
@@ -2,16 +2,17 @@
 
 import RIO
 
-import Sound.OpenAL qualified as OpenAL
+import Sound.OpenAL.FFI.AL qualified as AL
 import UnliftIO.Resource qualified as Resource
+import Foreign qualified
 
 class HasSource a where
-  getSource :: a -> OpenAL.Source
+  getSource :: a -> AL.Source
 
-instance HasSource OpenAL.Source where
+instance HasSource AL.Source where
   getSource = id
 
-instance HasSource (a, OpenAL.Source) where
+instance HasSource (a, AL.Source) where
   getSource = snd
 
 allocateCollectionWith
@@ -26,11 +27,13 @@
   loaded <- traverse action collection
 
   key <- Resource.register do
-    let sources = map getSource $ toList loaded
-    OpenAL.stop sources
-    for_ sources \source ->
-      OpenAL.buffer source OpenAL.$= Nothing
-    OpenAL.deleteObjectNames sources
+    -- let sources = map getSource $ toList loaded
+    -- stop loaded
+    -- for_ sources \source ->
+    --   OpenAL.buffer source OpenAL.$= Nothing
+    -- OpenAL.deleteObjectNames sources
+    Foreign.withArrayLen (map getSource $ toList loaded) \num ->
+      AL.alDeleteSources (fromIntegral num)
 
   pure (key, loaded)
 
@@ -40,7 +43,10 @@
 
 {-# INLINE play #-}
 play :: (Foldable t, HasSource a, MonadIO m) => t a -> m ()
-play = OpenAL.play . map getSource . toList
+play (toList -> sources) =
+  liftIO $
+    Foreign.withArrayLen (map getSource sources) \num ->
+      AL.alSourcePlayv (fromIntegral num)
 
 {-# INLINE stop1 #-}
 stop1 :: (HasSource a, MonadIO m) => a -> m ()
@@ -48,14 +54,15 @@
 
 {-# INLINE stop #-}
 stop :: (Foldable t, HasSource a, MonadIO m) => t a -> m ()
-stop = OpenAL.stop . map getSource . toList
+stop (toList -> sources) =
+  liftIO $
+    Foreign.withArrayLen (map getSource sources) \num ->
+      AL.alSourceStopv (fromIntegral num)
 
 {-# INLINE toggle #-}
 toggle :: (HasSource a, MonadIO m) => Bool -> a -> m ()
 toggle active src =
   if active then
-    OpenAL.play srcs
+    play1 src
   else
-    OpenAL.stop srcs
-  where
-    srcs = [getSource src]
+    stop1 src
diff --git a/src/Resource/Opus.hs b/src/Resource/Opus.hs
--- a/src/Resource/Opus.hs
+++ b/src/Resource/Opus.hs
@@ -10,7 +10,8 @@
 import Foreign qualified
 import Foreign.C.Types (CFloat(..))
 import GHC.Stack (withFrozenCallStack)
-import Sound.OpenAL qualified as OpenAL
+import Sound.OpenAL.FFI.AL qualified as AL
+import Sound.OpenAL.FFI.ALC qualified as ALC
 import Sound.OpusFile qualified as OpusFile
 
 import Resource.Source qualified as Resource
@@ -21,7 +22,7 @@
   , byteSource  :: Resource.Source
   }
 
-type Source = (Double, OpenAL.Source)
+type Source = (Double, AL.Source)
 
 load
   :: ( MonadIO m
@@ -29,7 +30,7 @@
      , HasLogFunc env
      , HasCallStack
      )
-  => OpenAL.Device
+  => ALC.Device
   -> Config
   -> m Source
 load _device Config{..} = do
@@ -39,9 +40,9 @@
   alFormat <-
     case OpusFile.pcmChannels pcm of
       Right OpusFile.Stereo ->
-        pure OpenAL.Stereo16
+        pure AL.FORMAT_STEREO16
       Right OpusFile.Mono ->
-        pure OpenAL.Mono16
+        pure AL.FORMAT_MONO16
       Left n -> do
         logError $ mconcat
           [ "unexpected channels in "
@@ -51,29 +52,38 @@
           ]
         exitFailure
 
-  !buffer <- liftIO OpenAL.genObjectName
+  buffer@(AL.Buffer bufId) <- liftIO $
+    Foreign.alloca \bufPtr -> do
+      AL.alGenBuffers 1 bufPtr
+      Foreign.peek bufPtr
+
   liftIO $
-    Foreign.withForeignPtr (OpusFile.pcmData pcm) \ptr -> do
-      let
-        mreg =
-          OpenAL.MemoryRegion ptr (fromIntegral $ OpusFile.pcmSize pcm)
-      OpenAL.bufferData buffer OpenAL.$=! OpenAL.BufferData mreg alFormat 48000
+    Foreign.withForeignPtr (OpusFile.pcmData pcm) \pcmData ->
+      AL.alBufferData
+        buffer
+        alFormat
+        (Foreign.castPtr pcmData)
+        (fromIntegral $ OpusFile.pcmSize pcm)
+        48000
 
-  !source <- liftIO $ OpenAL.genObjectName
+  source <- liftIO $
+    Foreign.alloca \sourcePtr -> do
+      AL.alGenSources 1 sourcePtr
+      Foreign.peek sourcePtr
+
   liftIO do
-    OpenAL.buffer source OpenAL.$=! Just buffer
-    OpenAL.loopingMode source OpenAL.$=! loopingMode'
-    OpenAL.sourceGain source OpenAL.$=! gain'
-    OpenAL.rolloffFactor source OpenAL.$=! 0 -- XXX: exempt from distance attenuation
+    AL.alSourcei source AL.BUFFER (fromIntegral bufId) -- XXX: unsigned to signed conversion
 
+    AL.alSourcei source AL.LOOPING (bool 0 1 loopingMode)
+
+    Foreign.with (CFloat gain) $
+      AL.alSourcefv source AL.GAIN
+
+    -- XXX: exempt from distance attenuation
+    Foreign.with (CFloat 0) $
+      AL.alSourcefv source AL.ROLLOFF_FACTOR
+
   pure (OpusFile.pcmTime pcm, source)
-  where
-    loopingMode' =
-      if loopingMode then
-        OpenAL.Looping
-      else
-        OpenAL.OneShot
-    gain' = CFloat gain
 
 -- TODO: extract to `opusfile`
 loadPCM :: MonadIO m => ByteString -> m (OpusFile.Pcm Int16)