diff --git a/doc/source/todo.rst b/doc/source/todo.rst
index 5aa12c7..f1733c5 100644
--- a/doc/source/todo.rst
+++ b/doc/source/todo.rst
@@ -74,4 +74,9 @@
 a list of clients that define it as their master. That would short-circuit
 Puppet's ``storeconfigs`` and Salt's ``mine``.
 
+Caching of classes in yaml\_fs
+------------------------------
+Right now, ``yaml\_fs`` opens each class file dozens of times during an
+inventory run. A class could be cached.
+
 .. include:: substs.inc