Wifi.connect() not executing its callback function

When modifying some simple example code to try and figure out what is going wrong, I noticed that the callback function inside wifi.connect is not executing and no console output is shown after console.log('start').

console.log('start');

var wifi = require("Wifi");

function onConnect(err) {
  console.log('begin'); // does not output
  if(err) {
    console.log("An error has occured :( ", err.message); // does not output
  } else {
    console.log("Connected with IP : ", wifi.getIP().ip); // does not output
  }
  console.log('end'); // does not output
}

wifi.connect("KNOWN_NETWORK", { password: "KNOWN_PASS" }, onConnect);