ES6+ in Cloud Functions for Firebase - preset-2015

CF4F-ES6-2|function01.js

// input - using CommonJS module syntax
const functions = require('firebase-functions')

module.exports.helloWorld = functions.https.onRequest((req, res) => {
  let world = `from Babelified Cloud Functions!`;
  res.status(200).send(`Hello ${world}`);
})

// Babel output - with Babel REPL settings:
// * preset-es2015
'use strict';

var functions = require('firebase-functions');

module.exports.helloWorld = functions.https.onRequest(function (req, res) {
  var world = 'from Babelified Cloud Functions!';
  res.status(200).send('Hello ' + world);
});