diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # ChangeLog for conduit-extra
 
+## 1.3.3
+
+* Disable buffering in process modules [#402](https://github.com/snoyberg/conduit/issues/402)
+
 ## 1.3.2
 
 * Expose `BuilderInput` and `FlushInput`.
diff --git a/Data/Conduit/Process.hs b/Data/Conduit/Process.hs
--- a/Data/Conduit/Process.hs
+++ b/Data/Conduit/Process.hs
@@ -29,8 +29,9 @@
 import Data.Streaming.Process.Internal
 import System.Exit (ExitCode (..))
 import Control.Monad.IO.Unlift (MonadIO, liftIO, MonadUnliftIO, withRunInIO, withUnliftIO, unliftIO)
-import System.IO (hClose)
+import System.IO (hClose, BufferMode (NoBuffering), hSetBuffering)
 import Data.Conduit
+import Data.Functor (($>))
 import Data.Conduit.Binary (sourceHandle, sinkHandle, sinkHandleBuilder, sinkHandleFlush)
 import Data.ByteString (ByteString)
 import Data.ByteString.Builder (Builder)
@@ -41,9 +42,9 @@
 #endif
 
 instance (r ~ (), MonadIO m, i ~ ByteString) => InputSource (ConduitM i o m r) where
-    isStdStream = (\(Just h) -> return $ sinkHandle h, Just CreatePipe)
+    isStdStream = (\(Just h) -> hSetBuffering h NoBuffering $> sinkHandle h, Just CreatePipe)
 instance (r ~ (), r' ~ (), MonadIO m, MonadIO n, i ~ ByteString) => InputSource (ConduitM i o m r, n r') where
-    isStdStream = (\(Just h) -> return (sinkHandle h, liftIO $ hClose h), Just CreatePipe)
+    isStdStream = (\(Just h) -> hSetBuffering h NoBuffering $> (sinkHandle h, liftIO $ hClose h), Just CreatePipe)
 
 -- | Wrapper for input source which accepts 'Data.ByteString.Builder.Builder's.
 -- You can pass 'Data.ByteString.Builder.Extra.flush' to flush the input. Note
@@ -68,9 +69,9 @@
   isStdStream = (\(Just h) -> return (FlushInput $ sinkHandleFlush h, liftIO $ hClose h), Just CreatePipe)
 
 instance (r ~ (), MonadIO m, o ~ ByteString) => OutputSink (ConduitM i o m r) where
-    osStdStream = (\(Just h) -> return $ sourceHandle h, Just CreatePipe)
+    osStdStream = (\(Just h) -> hSetBuffering h NoBuffering $> sourceHandle h, Just CreatePipe)
 instance (r ~ (), r' ~ (), MonadIO m, MonadIO n, o ~ ByteString) => OutputSink (ConduitM i o m r, n r') where
-    osStdStream = (\(Just h) -> return (sourceHandle h, liftIO $ hClose h), Just CreatePipe)
+    osStdStream = (\(Just h) -> hSetBuffering h NoBuffering $> (sourceHandle h, liftIO $ hClose h), Just CreatePipe)
 
 -- | Given a @CreateProcess@, run the process, with its output being used as a
 -- @Source@ to feed the provided @Consumer@. Once the process has completed,
diff --git a/Data/Conduit/Process/Typed.hs b/Data/Conduit/Process/Typed.hs
--- a/Data/Conduit/Process/Typed.hs
+++ b/Data/Conduit/Process/Typed.hs
@@ -25,18 +25,23 @@
 import Data.IORef (IORef, newIORef, readIORef, modifyIORef)
 import Control.Exception (throwIO, catch)
 import Control.Concurrent.Async (concurrently)
+import System.IO (hSetBuffering, BufferMode (NoBuffering))
 
 -- | Provide input to a process by writing to a conduit.
 --
 -- @since 1.2.1
 createSink :: MonadIO m => StreamSpec 'STInput (ConduitM S.ByteString o m ())
-createSink = CB.sinkHandle `fmap` createPipe
+createSink =
+  (\h -> liftIO (hSetBuffering h NoBuffering) >> CB.sinkHandle h)
+  `fmap` createPipe
 
 -- | Read output from a process by read from a conduit.
 --
 -- @since 1.2.1
 createSource :: MonadIO m => StreamSpec 'STOutput (ConduitM i S.ByteString m ())
-createSource = CB.sourceHandle `fmap` createPipe
+createSource =
+  (\h -> liftIO (hSetBuffering h NoBuffering) >> CB.sourceHandle h)
+  `fmap` createPipe
 
 -- | Internal function: like 'createSource', but stick all chunks into
 -- the 'IORef'.
diff --git a/conduit-extra.cabal b/conduit-extra.cabal
--- a/conduit-extra.cabal
+++ b/conduit-extra.cabal
@@ -1,5 +1,5 @@
 Name:                conduit-extra
-Version:             1.3.2
+Version:             1.3.3
 Synopsis:            Batteries included conduit: adapters for common libraries.
 Description:
     The conduit package itself maintains relative small dependencies. The purpose of this package is to collect commonly used utility functions wrapping other library dependencies, without depending on heavier-weight dependencies. The basic idea is that this package should only depend on haskell-platform packages and conduit.