I’ve noticed a couple errors already, such as this line about the kinds of dependencies available. (There are actually dev, peer, bundled and optional in addition to regular dependencies)

There are 2 kinds of package dependencies, “dependencies” and “devDependencies”.

That combined with the complexity introduced in step 3 by using Gulp instead of package.json scripts makes me hesitant to recommend this guide to anyone. For example, this would be the comparison to the gulp config:

{
  "scripts": {
    "clean": "rm -r lib/*",
    "build": "babel src --out-dir lib",
    "watch": "babel -w src --out-dir lib"
    "start": "node lib"
}

It seems to continue the complexity theme with the webpack config as well.