You need to do that, or include the global polyfill: https://babeljs.io/docs/usage/polyfill/ https://babeljs.io/docs/usage/polyfill/. If you're writing a libra

You need to do that, or include the global polyfill: https://babeljs.io/docs/usage/polyfill/ https://babeljs.io/docs/usage/polyfill/. If you're writing a library, use the runtime option. If you're writing a website or other standalone app, you should use the polyfill (especially if you use other libraries like React which depend on ES6 globals too).