diff --git a/README.md b/README.md
index f0d9d51..8592f25 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
+**Not ready for use!**
+
 feature | weaselab | fdb |
 |-|-|-|
 |based on|node-copying treap|node-copying treap|