I suggest you familiarize yourself with ES5/6 changes. For me classes and modules makes JS more like class-based language. During development on local cluster I

I suggest you familiarize yourself with ES5/6 changes. For me classes and modules makes JS more like class-based language. During development on local cluster I prefer to have one file/module per class. For me the biggest gotcha has been the increased use of promises, async/await in the numerous Web APIs.