diff --git a/README.txt b/README.txt
index 4e9802b..137f011 100644
--- a/README.txt
+++ b/README.txt
@@ -9,3 +9,13 @@ In other words, the code is here:
 
  https://github.com/mflatt/racket/tree/linklet/pkgs/expander
 
+The various branches of this repository demonstrate various
+simplified versions of Racket's macro expander.  From
+simple to more complex:
+
+* pico
+* nano
+* micro
+* mini
+* demi
+* ...and the full expander (see above)