diff --git a/flit_core/flit_core/common.py b/flit_core/flit_core/common.py
index 0adafc06..6625224b 100644
--- a/flit_core/flit_core/common.py
+++ b/flit_core/flit_core/common.py
@@ -347,6 +347,7 @@ class Metadata(object):
     obsoletes_dist = ()
     requires_external = ()
     provides_extra = ()
+    dynamic = ()
 
     metadata_version = "2.3"