Socket.io with au cli (1.3.1) and system js

Help Requests
1

Recenty tried to update from socket.io/socket.io.cliet from version 2.2 to version 4.0.1 using au cli with system js but had to roll back as socket.on does not get triggered. Just wondering if a change is required. Chrome debug into looks fine for the var socket in code example below

import io from 'socket.io-client'; 
...
constructor(api, router) {
    this.router = router
    this.api = api
    this.socketio = io('', {
      'reconnection': true,
      'reconnectionDelay': 500,
      'reconnectionDelayMax': 5000,
      'reconnectionAttempts': 10
    });
  }
...
 activate() {
    var socket = io.connect('http://localhost:8080');
    socket.on('food_ready', (eventData) => {
      let rec = { id: eventData.rating, title: eventData.name + ' - ' + eventData.rating }
      this.bakeries.push(eventData)
     console.log('data', eventData.name + ' - ' + eventData.rating)
    })
}