diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,8 @@
+# 1.0.8.2
+
+* Fix foldl1 not being "a strict left fold" as advertised.
+  [#115](https://github.com/snoyberg/mono-traversable/pull/115)
+
 # 1.0.8.1
 
 * Break on single elements and defer monoid concatenation until yield
diff --git a/Data/Conduit/Combinators.hs b/Data/Conduit/Combinators.hs
--- a/Data/Conduit/Combinators.hs
+++ b/Data/Conduit/Combinators.hs
@@ -717,7 +717,7 @@
 foldl1C f =
     await >>= maybe (return Nothing) loop
   where
-    loop prev = await >>= maybe (return $ Just prev) (loop . f prev)
+    loop !prev = await >>= maybe (return $ Just prev) (loop . f prev)
 STREAMING(foldl1, foldl1C, foldl1S, f)
 
 -- | A strict left fold on a chunked stream, with no starting value.
diff --git a/conduit-combinators.cabal b/conduit-combinators.cabal
--- a/conduit-combinators.cabal
+++ b/conduit-combinators.cabal
@@ -1,5 +1,5 @@
 name:                conduit-combinators
-version:             1.0.8.1
+version:             1.0.8.2
 synopsis:            Commonly used conduit functions, for both chunked and unchunked data
 description:         Provides a replacement for Data.Conduit.List, as well as a convenient Conduit module.
 homepage:            https://github.com/snoyberg/mono-traversable