class Config {
 constructor(config) {
  this.config = config;
 }

 get birlestir() {
  returnthis.config.nick +this.nick.password;
 }
}

 module.exports=newConfig({  nick:'Hebele',  password:'Hübele',});

const config = require('./config');

   console.log(config.birlestir); // HebeleHübele