fixtures/packaging/systemjs-builder/prod/build.js

var Builder = require('systemjs-builder');

var builder = new Builder('/', './config.js');
builder
  .buildStatic('./input.js', './output.js')
  .then(function() {
    console.log('Build complete');
  })
  .catch(function(err) {
    console.log('Build error');
    console.log(err);
  });