diff --git a/src/mirror-img.lisp b/src/mirror-img.lisp
index 3566ae4..8dcd91c 100644
--- a/src/mirror-img.lisp
+++ b/src/mirror-img.lisp
@@ -188,4 +188,4 @@ That is, 443 is implied by HTTPS, so nil is returned; but 998 wouldn’t be impl
 (defun pathname-leaf (pathname)
   "Given a pathname, return the entirety of the file leaf.
 That is, everything following the last directory name."
-  (car (last (cl-strings:split (namestring pathname) #\/))))
+  (car (last (split-sequence:split-sequence #\/ (namestring pathname)))))