diff --git a/dash.el b/dash.el
index 2cb00b8..2a4ffeb 100644
--- a/dash.el
+++ b/dash.el
@@ -414,7 +414,7 @@ FROM or TO may be negative."
 (defun -insert-at (n x list)
   "Returns a list with X inserted into LIST at position N."
   (let ((split-list (-split-at n list)))
-    (append (car split-list) (cons x (cadr split-list)))))
+    (nconc (car split-list) (cons x (cadr split-list)))))
 
 (defmacro --split-with (pred list)
   "Anaphoric form of `-split-with'."