Example of a bundling task for Angular 2 with gulp (so as to reduce http/xhr requests.) Works in the context of a project created through angular-cli.

gulpfile-ng-bundle-task.js

gulp.task('ng-bundle', function(done) {
    process.chdir('dist');

    let bundleFilename = 'app.bundle.js';

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

    let builder = new Builder();

    builder.loadConfig('system-config.js')
    .then(function() {
        return builder
            .buildStatic('main.js', bundleFilename, {
                normalize: true,
                minify: true,
                mangle: true,
                runtime: false
            });
    })
    .then(function() {
        console.log(`Bundle complete. \`stat ./dist/${bundleFilename}\``);
        done();
    })
    .catch(function (err) {
        console.log('error', err);
        console.log('ng-bundle failed.');
        process.exit(1);
    });
});