ES6 setup for MelonJS (using Webpack)

bootstrap.js

import game from './game';

import PlayerEntity from './entities/player';
import PlayScreen from './screens/play';
import TitleScreen from './screens/title';

class Bootstrap {

    constructor() {
        // Initialize the video.
        if (!me.video.init("screen",  me.video.CANVAS, 960, 640, true, 'auto')) {
            alert("Your browser does not support HTML5 canvas.");
            return;
        }

        // add "#debug" to the URL to enable the debug Panel
        if (document.location.hash === "#debug") {
            window.onReady(function () {
                me.plugin.register.defer(this, me.debug.Panel, "debug", me.input.KEY.V);
            });
        }

        // Initialize the audio.
        me.audio.init("mp3,ogg");

        // Set a callback to run when loading is complete.
        me.loader.onload = this.loaded.bind(this);

        // Load the resources.
        me.loader.preload({});

        // Initialize melonJS and display a loading screen.
        me.state.change(me.state.LOADING);
    }

    loaded() {
        me.state.set(me.state.MENU, new TitleScreen());
        me.state.set(me.state.PLAY, new PlayScreen());

        // add our player entity in the entity pool
        me.pool.register("mainPlayer", PlayerEntity);

        // Start the game.
        me.state.change(me.state.PLAY);     
    }

    static boot() {
        var bootstrap = new Bootstrap();

        // Mobile browser hacks
        if (me.device.isMobile && !navigator.isCocoonJS) {
            // Prevent the webview from moving on a swipe
            window.document.addEventListener("touchmove", function (e) {
                e.preventDefault();
                window.scroll(0, 0);
                return false;
            }, false);

            // Scroll away mobile GUI
            (function () {
                window.scrollTo(0, 1);
                me.video.onresize(null);
            }).defer();

            me.event.subscribe(me.event.WINDOW_ONRESIZE, function (e) {
                window.scrollTo(0, 1);
            });
        }

        return bootstrap;
    }
}

window.onReady(function onReady() {
    Bootstrap.boot();
});

game.js

class Game {
    constructor() {
        this.data = {
            score : 666,
        };
    }
};

export default new Game();

screen.js

import game from '../game';

class PlayScreen extends me.ScreenObject {
    /**
     *  action to perform on state change
     */
    onResetEvent() {
        me.game.world.addChild(new me.ColorLayer("background", "#ff0000", 0), 0);        
    }

    /**
     *  action to perform when leaving this screen (state change)
     */
    onDestroyEvent() {
    }
};

export default PlayScreen;