webpack.config.js

const TerserPlugin = require('terser-webpack-plugin');

const devMode = process.env.NODE_ENV !== 'production';
module.exports = {
  mode: devMode ? 'development' : 'production',
  devtool: devMode ? 'cheap-module-eval-source-map' : 'cheap-module-source-map',
  output: {
    filename: 'iu-toast.min.js',
    library: 'iToast',
    libraryExport: 'default',
    libraryTarget: 'umd'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        loaders: [
          'babel-loader',
          {
            loader: 'eslint-loader',
            options: {
              formatter: require('eslint-friendly-formatter'),
              fix: true
            }
          }
        ]
      }
    ]
  },
  optimization: {
    minimize: true,
    minimizer: [
      new TerserPlugin({
        parallel: 4,
        cache: true,
        terserOptions: {
          compress: {
            pure_funcs: ['console.log']
          },
          output: {
            comments: false
          }
        }
      })
    ]
  }
};