Converting from Custom Webpack Config to Rails Webpacker Config

  1. Compare your package.json and the dependencies in and avoid any duplicates. We don't want different versions of the same packages. We want the versions from rails/webpacker unless we specifically want to override them.
  2. Search the rails/webpacker repo for anything you're not sure about in terms of package names.
  3. run bin/webpack and make sure there are zero errors
  4. update webpack plugins and loaders to current or close to current
  5. Make sure that your bin/webpack and bin/webpacker match the latest on