webpack.config.js

const webpack = require('webpack');
const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');

//  The production mode

module.exports = {
  // entry point of our app
  entry: './client/index.js',
  output: {
    path: path.resolve(__dirname, 'build'),
    // publicPath: 'build',
    filename: 'bundle.js',
  },
  mode: process.env.NODE_ENV,
  module: {
    rules: [
      {
        test: /\.jsx?/,  // conditional  '.js(x)'
        exclude: /node_modules/,
        loader: 'babel-loader', // if it meets a conditional run it..
        options: {
          presets: ['@babel/env', '@babel/react', 
          {
            plugins: ['@babel/plugin-proposal-class-properties'
             , '@babel/plugin-transform-runtime'
          ],
          },
        ],
        }
      },
      {
        test: /\.(css|scss)$/,
        exclude: /node_modules/,
        use: [
          // Creates `style` nodes from JS strings
          "style-loader",
          // Translates CSS into CommonJS
          "css-loader",
          // Compiles Sass to CSS
          "sass-loader",
        ]
      },
      {
        test: /\.png|svg|jpg|gif$/,
        use: ["file-loader"],
      }
    ]
  },
  plugins: [new HtmlWebpackPlugin({ template: "index.html" })],
  devServer: {
    // static: {
    //     directory: path.join(__dirname, 'build'),
    //     publicPath: "/build",
    // },
    // compress: true,
    port: 8080,
    proxy: {
      '/api/leaders': 'http://localhost:3000',
    },
  },
  performance: {
    hints: false,
    maxEntrypointSize: 512000,
    maxAssetSize: 512000
  },
  resolve: {
    modules: [__dirname, "client", "node_modules"],
    extensions: ["*", ".js", ".jsx", ".tsx", ".ts"],
  },
};