diff --git a/src/intro_to_uxn_programming.gmo b/src/intro_to_uxn_programming.gmo
index 896cf1e..24ab7b4 100644
--- a/src/intro_to_uxn_programming.gmo
+++ b/src/intro_to_uxn_programming.gmo
@@ -89,6 +89,7 @@ We will use the learn-uxn website by metasyn, that requires a web browser with j
 => https://wiki.xxiivv.com/site/varvara.html varvara documentation
 => https://akkartik.github.io/mu/tutorial/converter.html decimal to hexadecimal converter
 => https://100r.co/site/nasu.html 100R - nasu spritesheet editor
+=> https://git.sr.ht/~rabbits/uxn uxn source code
 => ./hexadecimal.gmi {hexadecimal}
 
 ## and more