Is it possible to use Fast Models directly in c++ without using simgen?

For example, I have my own model of a UART on my SoC, can I just make it expose a SerialData port, and connect it to a TelnetTerminal component directly in C++? Sometimes I want to use a model from Fast Models library, but I don't want to draw a sgcanvas diagram. Directly instantiating a component in c++ is more handy.