next.config.js

// This file is not going through babel transformation.
// So, we write it in vanilla JS
// (But you could use ES2015 features supported by your Node.js version)

const debug = process.env.NODE_ENV !== "production";

module.exports = {
  exportPathMap: function () {
    return {
      "/": { page: "/" },
      "/about": { page: "/about" },
    }
  },
  //assetPrefix: '',
  assetPrefix: !debug ? '/Next-gh-page-example/' : '',
  webpack: (config, { dev }) => {
    // Perform customizations to webpack config
    // console.log('webpack');
    // console.log(config.module.rules, dev);
    config.module.rules = config.module.rules.map(rule => {
      if(rule.loader === 'babel-loader') {
        rule.options.cacheDirectory = false
      }
      return rule
    })
    // Important: return the modified config
    return config
  }/*,
  webpackDevMiddleware: (config) => {
    // Perform customizations to webpack dev middleware config
    // console.log('webpackDevMiddleware');
    // console.log(config);
    // Important: return the modified config
    return config
  }, */
}