function genConfig (opts) {
  const config = {
    input: {
      input: opts.input,
      plugins: [
        replace({
          __VERSION__: version
        }),
        babel({
          exclude: 'node_modules/**'
        })
      ]
    },
    output: {
      banner,
      file: opts.file,
      format: opts.format,
      name: 'Storage'
    }
  }

  if (opts.env) {
    config.input.plugins.unshift(replace({
      'process.env.NODE_ENV': JSON.stringify(opts.env)
    }))
  }

  return config
}
good-storage v${version}
(c) ${new Date().getFullYear()} ustbhuangyi