Agreed, hence why composite widget support in GTKmm would be really nice. In Vala you just make a normal class inheriting from whatever your base widget is, decorate it with a [GtkTemplate] attribute and whenever you construct that widget it will use the gtkbuilder XML you referenced in the attribute to construct the widget, binding all the callbacks referenced in the XML with the respective methods on the class.<p>Until recently C++ hasn&#x27;t even had compile time reflection that would allow this to work very well, now that C++14&#x2F;C++17 are adding that I think this would be very doable.