code: function Bootprint (withData, targetDir) {
    /**
     * Run Bootprint and write the result to the specified target directory
     * @param options {object} options passed to Customize#run()
     * @returns {Promise} a promise for the completion of the build
     */
    this.generate = function generate (options) {
      return withData.run(options).then(write(targetDir))
    }
  
    /**
     * Run the file watcher to watch all files loaded into the
     * current Bootprint-configuration.
     * The watcher run Bootprint every time one the the input files, templates or helpers changes.
     * @returns {EventEmitter} an EventEmitter that sends an `update`-event after each
     *   build, but before the files are written to disc.
     */
    this.watch = function () {
      return withData.watch().on('update', write(targetDir))
    }
  }
docs: The old Bootprint interface
  @constructor