It's not really a problem now. I use the auto-transpilation trick with Babel. You can see a small example in my repo: https://github.com/odiroot/songs-to-spoti

It's not really a problem now. I use the auto-transpilation trick with Babel. You can see a small example in my repo: https://github.com/odiroot/songs-to-spotify/blob/master/src/syncer.js https://github.com/odiroot/songs-to-spotify/blob/master/src/... Then in required modules you're free to use ES2015.