diff --git a/src/Diff.hs b/src/Diff.hs
index 9da5fadfd..4fff55707 100644
--- a/src/Diff.hs
+++ b/src/Diff.hs
@@ -41,11 +41,4 @@ mergeMaybe transform = cata algebra . fmap transform
           Keyed i -> Keyed (Map.fromList (Map.toList i >>= (\ (k, v) -> maybe [] (pure . (,) k) v)))
 
 beforeTerm :: Diff leaf annotation -> Maybe (Term leaf annotation)
-beforeTerm = cata algebra
-  where algebra :: FreeF (CofreeF (Syntax leaf) (Both annotation)) (Patch (Term leaf annotation)) (Maybe (Term leaf annotation)) -> Maybe (Term leaf annotation)
-        algebra (Pure patch) = before patch
-        algebra (Free (annotations :< syntax)) = Just . cofree $ Both.fst annotations :< case syntax of
-          Leaf s -> Leaf s
-          Indexed i -> Indexed (catMaybes i)
-          Fixed i -> Fixed (catMaybes i)
-          Keyed i -> Keyed (Map.fromList (Map.toList i >>= (\ (k, v) -> maybe [] (pure . (,) k) v)))
+beforeTerm = mergeMaybe before