diff --git a/extra/trails/trails.factor b/extra/trails/trails.factor
index 5781f6ee09..cea5ece9f7 100644
--- a/extra/trails/trails.factor
+++ b/extra/trails/trails.factor
@@ -1,5 +1,5 @@
 
-USING: kernel accessors locals namespaces sequences threads
+USING: kernel accessors locals namespaces sequences sequences.lib threads
        math math.order math.vectors
        calendar
        colors opengl ui ui.gadgets ui.gestures ui.render