diff --git a/README.md b/README.md
index 5e44fda..087251c 100644
--- a/README.md
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@@ -2,6 +2,9 @@
 
 Specification and discussions about language design.
 
+A toy implementation is in `toy-impl`, requires python 3.9.
+
+
 ## Referencing Python Variables
 The kernel is allowed to read Python variables.