node.js - Synchronous System.import() in ES6

Question

Is there a way for System.import('module') to load 'module' synchronously?
Just like with require('module) in nodejs..

I was hoping to do something like this:

let defaultConf = {port: 5555}; 
let envJS = './conf/env/' + process.env.NODE_ENV + '.js';
let conf = System.import(envJS);
_.merge(default_conf, conf);
export default defaultConf;