diff --git a/pep-3156.txt b/pep-3156.txt
index ecba82937..7ea3dc5ba 100644
--- a/pep-3156.txt
+++ b/pep-3156.txt
@@ -987,6 +987,9 @@ Open Issues
 - Need to handle os.fork().  (This may be up to the selector classes
   in Tulip's case.)
 
+- Perhaps start_serving() needs a way to pass in an existing socket
+  (e.g. gunicorn would need this).
+
 - We might introduce explicit locks, though these will be a bit of a
   pain to use, as we can't use the ``with lock: block`` syntax
   (because to wait for a lock we'd have to use ``yield from``, which