diff --git a/libs/canvas/wscript b/libs/canvas/wscript
index 83ba2223ea..dc3f741658 100644
--- a/libs/canvas/wscript
+++ b/libs/canvas/wscript
@@ -50,6 +50,7 @@ canvas_sources = [
         'polygon.cc',
         'rectangle.cc',
         'root_group.cc',
+        'ruler.cc',
         'scroll_group.cc',
         'stateful_image.cc',
         'text.cc',