diff --git a/emacs.el b/emacs.el
index 2075521..0da3167 100644
--- a/emacs.el
+++ b/emacs.el
@@ -2223,7 +2223,7 @@ ARG is ignored."
     ;; ack
     ("ack"
      (executable-find "ack")
-     "ack --nocolor --nogroup --nopager ")
+     "ack --nocolor --nogroup --nopager --with-filename")
 
     ;; gnu global
     ("global"