diff --git a/deferred-folds.cabal b/deferred-folds.cabal
--- a/deferred-folds.cabal
+++ b/deferred-folds.cabal
@@ -1,5 +1,5 @@
 name: deferred-folds
-version: 0.7.2
+version: 0.8
 category: Folding
 synopsis: Abstractions over deferred folds
 description:
diff --git a/library/DeferredFolds/Defs/Unfoldr.hs b/library/DeferredFolds/Defs/Unfoldr.hs
--- a/library/DeferredFolds/Defs/Unfoldr.hs
+++ b/library/DeferredFolds/Defs/Unfoldr.hs
@@ -58,11 +58,6 @@
 fold :: Fold input output -> Unfoldr input -> output
 fold (Fold step init extract) = extract . foldl' step init
 
-{-| Unlift a monadic unfold -}
-{-# INLINE unfoldrM #-}
-unfoldrM :: UnfoldrM Identity input -> Unfoldr input
-unfoldrM (UnfoldrM runFoldM) = Unfoldr (\ step init -> runIdentity (runFoldM (\ a b -> return (step a b)) init))
-
 {-| Construct from any foldable -}
 {-# INLINE foldable #-}
 foldable :: Foldable foldable => foldable a -> Unfoldr a
@@ -154,9 +149,9 @@
 reverse (Unfoldr unfoldr) = Unfoldr $ \ step -> unfoldr (\ a f -> f . step a) id
 
 {-|
-Lift into an unfold, which produces pairs with index.
+Lift into an unfold, which produces pairs with right-associative index.
 -}
-zipWithIndex :: Unfoldr a -> Unfoldr (Int, a)
-zipWithIndex (Unfoldr unfoldr) = Unfoldr $ \ step init -> snd $ unfoldr
+zipWithReverseIndex :: Unfoldr a -> Unfoldr (Int, a)
+zipWithReverseIndex (Unfoldr unfoldr) = Unfoldr $ \ step init -> snd $ unfoldr
   (\ a (index, state) -> (succ index, step (index, a) state))
   (0, init)