Use the wf:comet function as a gen_server

In nitrogen 1, I was able to turn the fun that's the argument to wf:comet/1 into a gen_server, like this:

State = #state{...},
wf:comet(fun() ->
             gen_server:enter_loop(?MODULE, [], State)
         end).

Nitrogen 2.x doesn't let me do that anymore, because the fun inside the comet loop is not started inside a proc_lib hierarchy.
I really appreciate it if I could do what's shown above because my comet function do behave as a gen_server and it's a pitty that I can not use gen_server:call/2 and gen_server:cast/2 to send messages to it.

Thanks.