Total newbie - is QML compiled
There is a detail blog post answering this. It is the first of a 4 part series.
int main(int argc, char *argv)
QApplication app(argc, argv);
The qml files themselves can also be embedded into the executable. When deploying you would also usually ship the Qt .dlls together with your application.
Thanks folks - the link looks like a very interesting (and educational) read.