diff --git a/modules/rosenthal/examples/guix/channels.scm b/modules/rosenthal/examples/guix/channels.txt
similarity index 97%
rename from modules/rosenthal/examples/guix/channels.scm
rename to modules/rosenthal/examples/guix/channels.txt
index 6d06659..f42f343 100644
--- a/modules/rosenthal/examples/guix/channels.scm
+++ b/modules/rosenthal/examples/guix/channels.txt
@@ -1,3 +1,5 @@
+;;; -*- mode: scheme -*-
+
 ;; info "(guix) Channels"
 ;; https://guix.gnu.org/manual/devel/en/html_node/Channels.html