I'm just installing the promise-polyfill as part of my package.json dependencies: "promise-polyfill" : "^6.0.2" And then in my index.js Webpack entry, I'm importing it along with all my other imports: import './promise-polyfill' import jquery from 'jquery' import tether from 'tether' import bootstrap from 'bootstrap' import './scss/base.scss' ; import { app } from './app' app.$mount( '#app' ) app.js , btw, contains my regular Vue imports: import Vue from 'vue' import { sync } from 'vuex-router-sync' import App from './components/App' import router from './router' import store from './store' sync(store, router) import Meta from 'vue-meta' Vue.use(Meta) const app = new Vue({ router, store, Meta, ...App }) export { app, Meta, router, store }