diff --git a/README.md b/README.md
index ddb2071..4c697e1 100644
--- a/README.md
+++ b/README.md
@@ -105,3 +105,7 @@ devkit, which uses the CC430F6137.  See Adam Laurie's
 project for an early example of sniffing OOK traffic and replaying it
 from a watch.
 
+[F91 Kepler](https://gitlab.com/_Pegor/kepler_fw) is an OLED and BTLE
+replacement for the Casio F91W module.  It uses a CC2640 and has some
+rather good documentation.
+