diff --git a/src/Ratchet/Server/IoConnection.php b/src/Ratchet/Server/IoConnection.php
index 9f864bb9..7574aaae 100644
--- a/src/Ratchet/Server/IoConnection.php
+++ b/src/Ratchet/Server/IoConnection.php
@@ -6,6 +6,7 @@
 /**
  * {@inheritdoc}
  */
+#[\AllowDynamicProperties]
 class IoConnection implements ConnectionInterface {
     /**
      * @var \React\Socket\ConnectionInterface