diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index dfd76bed..2cf08f30 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -74,3 +74,5 @@ An optional [REPL](https://en.wikipedia.org/wiki/Read%E2%80%93eval%E2%80%93print
 Listen on a TCP / HTTP+REST port.
 
 A web-based version.
+
+Support a more secure saved-games format than the pickle-based-one.