diff --git a/buildstream/utils.py b/buildstream/utils.py
index 968d87f7bf83177476249f4c8f9ba927004103dc..a0db963da57e9f986332a801a4e48f2677386115 100644
--- a/buildstream/utils.py
+++ b/buildstream/utils.py
@@ -505,7 +505,7 @@ def get_bst_version():
                         .format(__version__))
 
 
-def move_atomic(source, destination, ensure_parents=True):
+def move_atomic(source, destination, *, ensure_parents=True):
     """Move the source to the destination using atomic primitives.
 
     This uses `os.rename` to move a file or directory to a new destination.