diff --git a/src/Interpreter.hs b/src/Interpreter.hs
index d38351f8d..649571a36 100644
--- a/src/Interpreter.hs
+++ b/src/Interpreter.hs
@@ -55,7 +55,7 @@ run comparable (Free (Recursive (annotation1 :< a) (annotation2 :< b) f)) = run
 run comparable (Free (ByKey a b f)) = run comparable $ f byKey where
   byKey = Map.fromList $ toKeyValue <$> List.union aKeys bKeys
   toKeyValue key | List.elem key deleted = (key, Pure . Delete $ a ! key)
-  toKeyValue key | List.elem key inserted = (key, Pure . Delete $ b ! key)
+  toKeyValue key | List.elem key inserted = (key, Pure . Insert $ b ! key)
   toKeyValue key = (key, interpret comparable (a ! key) (b ! key))
   aKeys = Map.keys a
   bKeys = Map.keys b