webpack.config.js

const resolve = {
  alias: {
    'netcode': `${__dirname}/`,
  }
}

const clientConfig = {
  target: 'web',
  entry: './src/client/index.js',
  output: {
    filename: 'client.js',
    path: __dirname,
    library: 'netcode',
    libraryTarget: 'umd'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: { presets: ['@babel/preset-env'] }
        }
      }
    ]
  },
  resolve,
};

const serverConfig = {
  target: 'node',
  entry: './src/server/index.js',
  output: {
    filename: 'server.js',
    path: `${__dirname}`,
    library: 'netcode',
    libraryTarget: 'umd'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: { presets: [[ '@babel/preset-env', { targets: { node: true } } ]] }
        }
      }
    ]
  },
  resolve,
};

module.exports = [ serverConfig, clientConfig ];