CMS Manual Initialization produces large bundle

HI, I’m currently trying the new Feature Manual Initialization, described here: Beta Features! | Netlify CMS | Open-Source Content Management System.

I import the CMS object like described in the docs in an index.js file:

import CMS, { init } from 'netlify-cms';

When I process this file with webpack and babel the bundle has a size of about 5 MB.

My webpack rules looks like this:

rules: [
        test: /\.m?js$/,
        exclude: /(node_modules)/,
        use: [
            loader: 'babel-loader',
            options: {
              cacheDirectory: true,
              presets: ['@babel/preset-env'],
              plugins: ['@babel/plugin-transform-runtime']

Does anyone has tips how to reduce the file size?

Run the terser plug-in to minimize your js, that’ll make a lot of difference