diff --git a/simuvex/storage/file.py b/simuvex/storage/file.py
index <HASH>..<HASH> 100644
--- a/simuvex/storage/file.py
+++ b/simuvex/storage/file.py
@@ -220,6 +220,10 @@ class SimFile(SimStatePlugin):
             [ o.content for o in others ], merge_conditions, common_ancestor=common_ancestor
         )
 
+    def widen(self, others):
+        return self.merge(others, [])
+
+
 class SimDialogue(SimFile):
     """
     Emulates a dialogue with a program. Enables us to perform concrete short reads.
Add a dummy implementation for widening SimFiles.