diff --git a/.emacs.d/site-lisp/oni.el b/.emacs.d/site-lisp/oni.el
index 9561227..a0aa003 100644
--- a/.emacs.d/site-lisp/oni.el
+++ b/.emacs.d/site-lisp/oni.el
@@ -294,6 +294,7 @@ If COUNT has been specified indent by that much, otherwise look at
 (defun oni:markdown-mode-func ()
   "Function for `markdown-mode-hook'."
   (setq-local comment-auto-fill-only-comments nil)
+  (setq-local whitespace-style '(face trailing))
   (auto-fill-mode)
   (whitespace-mode))
 
@@ -411,7 +412,9 @@ When dealing with braces, add another line and indent that too."
   (rainbow-delimiters-mode)
   (setq fci-rule-column 79
         fill-column 72)
-  (fci-mode))
+  (setq-local whitespace-style '(tab-mark))
+  (fci-mode)
+  (whitespace-mode))
 
 (defun oni:raise-ansi-term (arg)
   "Create or show an `ansi-term' buffer."