diff --git a/src/toolbars/ControlToolBar.h b/src/toolbars/ControlToolBar.h
index aa898467b..09ff74373 100644
--- a/src/toolbars/ControlToolBar.h
+++ b/src/toolbars/ControlToolBar.h
@@ -38,6 +38,8 @@ class SelectedRegion;
 // Defined in Project.h
 enum class PlayMode : int;
 
+using WaveTrackArray = std::vector < std::shared_ptr < WaveTrack > >;
+
 // In the GUI, ControlToolBar appears as the "Transport Toolbar". "Control Toolbar" is historic.
 class ControlToolBar final : public ToolBar {