diff --git a/stack.yaml b/stack.yaml
index e4fc748..6c8a0dd 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: lts-8.13
+resolver: lts-11.9
 
 packages:
 - tensorflow
@@ -16,12 +16,11 @@ packages:
 extra-deps:
 - snappy-framing-0.1.1
 - snappy-0.2.0.2
-# TODO: Remove these once the new versions are in lts-9.
+# `haskell-src-exts < 1.20` is needed due the dependency on
+# `proto-lens-protoc < 0.3` in the `tensorflow-proto` package:
+- haskell-src-exts-1.19.1
 - proto-lens-protobuf-types-0.2.2.0
-- proto-lens-0.2.2.0
-- proto-lens-descriptors-0.2.2.0
 - proto-lens-protoc-0.2.2.3
-- lens-labels-0.1.0.2
 
 # For Mac OS X, whose linker doesn't use this path by default
 # unless you run `xcode-select --install`.
diff --git a/tensorflow-logging/src/TensorFlow/Logging.hs b/tensorflow-logging/src/TensorFlow/Logging.hs
index fac2eed..4eb5088 100644
--- a/tensorflow-logging/src/TensorFlow/Logging.hs
+++ b/tensorflow-logging/src/TensorFlow/Logging.hs
@@ -58,7 +58,7 @@ import Control.Monad.Catch (MonadMask, bracket)
 import Control.Monad.IO.Class (MonadIO, liftIO)
 import Control.Monad.Trans.Resource (runResourceT)
 import Data.ByteString (ByteString)
-import Data.Conduit ((=$=))
+import Data.Conduit ((.|))
 import Data.Conduit.TQueue (sourceTBMQueue)
 import Data.Default (def)
 import Data.Int (Int64)
@@ -113,8 +113,8 @@ newEventWriter logdir = do
     let writer = EventWriter q done
         consumeQueue = runResourceT $ Conduit.runConduit $
             sourceTBMQueue q
-            =$= Conduit.map (L.fromStrict . encodeMessage)
-            =$= sinkTFRecords filename
+            .| Conduit.map (L.fromStrict . encodeMessage)
+            .| sinkTFRecords filename
     _ <- forkFinally consumeQueue (\_ -> putMVar done ())
     logEvent writer $ def & wallTime .~ t
                           & fileVersion .~ T.pack "brain.Event:2"
diff --git a/tensorflow-logging/tests/LoggingTest.hs b/tensorflow-logging/tests/LoggingTest.hs
index 8b874c4..19a9c94 100644
--- a/tensorflow-logging/tests/LoggingTest.hs
+++ b/tensorflow-logging/tests/LoggingTest.hs
@@ -16,7 +16,7 @@
 module Main where
 
 import Control.Monad.Trans.Resource (runResourceT)
-import Data.Conduit ((=$=))
+import Data.Conduit ((.|))
 import Data.Default (def)
 import Data.List ((\\))
 import Data.ProtoLens (encodeMessage, decodeMessageOrDie)
@@ -53,7 +53,7 @@ testEventWriter = testCase "EventWriter" $
         files <- listDirectory dir
         assertEqual "One file exists after" 1 (length files)
         records <- runResourceT $ Conduit.runConduit $
-            sourceTFRecords (dir </> head files) =$= Conduit.consume
+            sourceTFRecords (dir </> head files) .| Conduit.consume
         assertBool "File is not empty" (not (null records))
         let (header:body) = decodeMessageOrDie . BL.toStrict <$> records
         assertEqual "Header has expected version"
@@ -71,7 +71,7 @@ testLogGraph = testCase "LogGraph" $
             logGraph eventWriter graphBuild
         files <- listDirectory dir
         records <- runResourceT $ Conduit.runConduit $
-            sourceTFRecords (dir </> head files) =$= Conduit.consume
+            sourceTFRecords (dir </> head files) .| Conduit.consume
         let (_:event:_) = decodeMessageOrDie . BL.toStrict <$> records
         assertEqual "First record expected to be Event containing GraphDef" expectedGraphEvent event
 
diff --git a/tensorflow-records-conduit/src/TensorFlow/Records/Conduit.hs b/tensorflow-records-conduit/src/TensorFlow/Records/Conduit.hs
index 9728233..d801f81 100644
--- a/tensorflow-records-conduit/src/TensorFlow/Records/Conduit.hs
+++ b/tensorflow-records-conduit/src/TensorFlow/Records/Conduit.hs
@@ -30,24 +30,24 @@ import Control.Monad.Catch (MonadThrow)
 import Control.Monad.Trans.Resource (MonadResource)
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as BL
-import Data.Conduit ((=$=), Conduit, Consumer, Producer)
+import Data.Conduit ((.|), ConduitT)
 import Data.Conduit.Binary (sinkFile, sourceFile)
 import Data.Conduit.Cereal (conduitGet2, conduitPut)
 
 import TensorFlow.Records (getTFRecord, putTFRecord)
 
 -- | Decode TFRecords from a stream of bytes.
-decodeTFRecords :: MonadThrow m => Conduit B.ByteString m BL.ByteString
+decodeTFRecords :: MonadThrow m => ConduitT B.ByteString BL.ByteString m ()
 decodeTFRecords = conduitGet2 getTFRecord
 
 -- | Read TFRecords from a file.
-sourceTFRecords :: (MonadResource m, MonadThrow m) => FilePath -> Producer m BL.ByteString
-sourceTFRecords path = sourceFile path =$= decodeTFRecords
+sourceTFRecords :: (MonadResource m, MonadThrow m) => FilePath -> ConduitT i BL.ByteString m ()
+sourceTFRecords path = sourceFile path .| decodeTFRecords
 
 -- | Encode TFRecords to a stream of bytes.
-encodeTFRecords :: Monad m => Conduit BL.ByteString m B.ByteString
+encodeTFRecords :: Monad m => ConduitT BL.ByteString B.ByteString m ()
 encodeTFRecords = conduitPut putTFRecord
 
 -- | Write TFRecords to a file.
-sinkTFRecords :: (MonadResource m) => FilePath -> Consumer BL.ByteString m ()
-sinkTFRecords path = encodeTFRecords =$= sinkFile path
+sinkTFRecords :: (MonadResource m) => FilePath -> ConduitT BL.ByteString o m ()
+sinkTFRecords path = encodeTFRecords .| sinkFile path