diff --git a/TODO.md b/TODO.md
index 71cea43..4bc2cf4 100644
--- a/TODO.md
+++ b/TODO.md
@@ -38,6 +38,7 @@
     is stopped, which might lead to various issues.
 
 * aquatic_ws
+  * ipv6 only flag
   * load test cpu pinning
   * test with multiple socket and request workers
   * should it send back error on message parse error, or does that