diff --git a/Data/Conduit.hs b/Data/Conduit.hs
--- a/Data/Conduit.hs
+++ b/Data/Conduit.hs
@@ -48,6 +48,7 @@
     , ($$+)
     , ($$++)
     , ($$+-)
+    , ($=+)
     , unwrapResumable
 
       -- * Flushing
@@ -91,6 +92,7 @@
 infixr 0 $$+
 infixr 0 $$++
 infixr 0 $$+-
+infixl 1 $=+
 
 -- | The connect operator, which pulls data from a source and pushes to a sink.
 -- If you would like to keep the @Source@ open to be used for other
@@ -306,6 +308,12 @@
     final
     return res
 {-# INLINE ($$+-) #-}
+
+-- | Left fusion for a resumable source.
+--
+-- Since 1.0.16
+($=+) :: Monad m => ResumableSource m a -> Conduit a m b -> ResumableSource m b
+ResumableSource src final $=+ sink = ResumableSource (src $= sink) final
 
 -- | Provide for a stream of data that can be flushed.
 --
diff --git a/conduit.cabal b/conduit.cabal
--- a/conduit.cabal
+++ b/conduit.cabal
@@ -1,5 +1,5 @@
 Name:                conduit
-Version:             1.0.15.1
+Version:             1.0.16
 Synopsis:            Streaming data processing library.
 Description:
     @conduit@ is a solution to the streaming data problem, allowing for production, transformation, and consumption of streams of data in constant memory. It is an alternative to lazy I\/O which guarantees deterministic resource handling, and fits in the same general solution space as @enumerator@\/@iteratee@ and @pipes@. For a tutorial, please visit <https://haskell.fpcomplete.com/user/snoyberg/library-documentation/conduit-overview>.