Erlang SIP - how can I link it with jssip or flutter-webrtc/dart-sip-ua?

my project is imboy/websocket_handler.erl at main · imboy-pub/imboy · GitHub

How to use poroh/ersip as the server and flutter-webrtc/dart-sip-ua as the client

I have clone poroh/piraha running on macOS. How can I link it with jssip or flutter-webrtc/dart-sip-ua ?
I have just touched SIP. May I ask for guidance?