diff --git a/gtk2_ardour/wscript b/gtk2_ardour/wscript
index f703782698..3a6a14e767 100644
--- a/gtk2_ardour/wscript
+++ b/gtk2_ardour/wscript
@@ -164,6 +164,7 @@ gtk2_ardour_sources = [
         'missing_filesource_dialog.cc',
         'missing_plugin_dialog.cc',
         'mixer_snapshot_dialog.cc',
+        'mixer_snapshot_substitution_dialog.cc',
         'mixer_group_tabs.cc',
         'mixer_strip.cc',
         'mixer_ui.cc',