diff --git a/nix/config/emacs/init.el b/nix/config/emacs/init.el
index 8813bc7..017f6d6 100644
--- a/nix/config/emacs/init.el
+++ b/nix/config/emacs/init.el
@@ -1,3 +1,5 @@
+;; -*- lexical-binding: t; -*-
+
 (add-hook 'emacs-startup-hook
           (lambda ()
             (message "tobmacs loaded in %s."