diff --git a/shells/docker.nix b/shells/docker.nix
index 865248c..154547f 100644
--- a/shells/docker.nix
+++ b/shells/docker.nix
@@ -1,3 +1,4 @@
+# This file is controlled by /etc/dotfiles/README.org
 { pkgs ? import <nixpkgs> { } }:
 
 with pkgs;