webpack.dev.config.js

const path = require('path')
const { HotModuleReplacementPlugin, DefinePlugin } = require('webpack')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const ESLintPlugin = require('eslint-webpack-plugin')
const dotenv = require('dotenv')

module.exports = {
  mode: 'development',
  output: {
    publicPath: '/'
  },
  entry: './index.web.js',
  module: {
    rules: [
      {
        test: /\.(js)x?$/i,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            cacheDirectory: true,
            presets: ['module:metro-react-native-babel-preset'],
            plugins: [
              'react-native-web',
              [
                'module-resolver',
                {
                  alias: {
                    '^react-native$': 'react-native-web'
                  }
                }
              ]
            ]
          }
        }
      },
      {
        test: /\.(png|svg|jpg|gif)$/,
        use: ['file-loader']
      }
    ]
  },

  resolve: {
    alias: {
      'react-native$': 'react-native-web'
    },
    extensions: ['.web.js', '.jsx', '.js']
  },

  plugins: [
    new HtmlWebpackPlugin({
      template: 'public/index.html'
    }),
    new HotModuleReplacementPlugin(),
    new ESLintPlugin({
      extensions: ['js', 'jsx']
    }),
    new DefinePlugin({
      'process.env': JSON.stringify(dotenv.config().parsed)
    })
  ],

  devtool: 'inline-source-map',
  devServer: {
    static: path.join(__dirname, 'dist'),
    historyApiFallback: true,
    port: 4000,
    open: true
  }
}