next.config.js

const path = require('path');

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

module.exports = {
  basePath: !debug ? 'https://sammiepls.github.io/' : '',
  sassOptions: {
    data: '@import "path/to/global.scss";',
    includePaths: [path.join(__dirname, 'styles')],
  },
  exportPathMap: function () {
    return {
      '/': { page: '/' },
      //'/about': { page: '/about' },
    };
  },
  //assetPrefix: '',
  assetPrefix: !debug ? 'https://sammiepls.github.io/' : '',
  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
  }, */,
};