diff --git a/literate-build.org b/literate-build.org
index 69967af..915fe0a 100644
--- a/literate-build.org
+++ b/literate-build.org
@@ -358,6 +358,8 @@ PROPS is used as an aid in getting the right information from the file."
 Finally the last function mushes it all together and actually generates an =index.org= file. I just looks through the =posts/= directory and finds any files that start with a date. It compares the last modification time of the =index.org= and that of the latest modified post, and skips generating if the =index.org= is newer. Then it takes the 30 latest posts and extracts the necessary information from them and writes it all into =index.org=.
 
 #+begin_src emacs-lisp
+(require 'dash)
+
 (defun publish-generate-index (props)
   "Generate an index from my posts.
 Argument PROPS
@@ -380,7 +382,7 @@ Argument PROPS
           (insert "\n")
           (apply 'insert
                  (mapcar (lambda (file) (publish-extract-summary-from-file file props))
-                         (take 30 (reverse files))))
+                         (-take 30 (reverse files))))
           (write-file "posts/index.org"))))))
 #+end_src