Serving dynamic application (Flask) with LightHTTPd on Piratebox

I have a Python Flask application, and a Raspberry Pi ruing Raspbian on which I installed Piratebox to tu it into a Wifi hub. I'd like to modify the Piratebox homepage to serve my application. I know Piratebox uses Lighthttpd but I found nothing in its config files that I could modify.

Could someone explain me how to do that, please ? I'm a total begier in that sort of things.

Thanks in advance