This is a demo for a group voice chat using peerjs to handle WebRTC and socket.io to help clients connect.
You need to generate a self-signed certificate to run this as voice media can only be used over secure connections:
openssl genrsa -out key.pem
openssl req -new -key key.pem -out csr.pem
openssl x509 -req -days 9999 -in csr.pem -signkey key.pem -out cert.pem
rm csr.pem
Install dependencies with npm install and run with npm start. Open https://127.0.0.1:3000, https://yourexternalip:3000, or https://yourlanip:3000 in a supporting browser on multiple devices.