Combining two sources in a single Gulp task

gulpfile.js

var gulp = require('gulp');
var es = require('event-stream');
var coffee = require('gulp-coffee');
var concat = require('gulp-concat');
var uglify = require('gulp-uglify');
var gutil = require('gulp-util');

var paths = {
  coffeeSrc: 'assets/coffee/**/*.coffee',
  coffeeDest: 'assets/js',
  buildScriptsSrc: [
    'bower_components/jquery/jquery.min.js',
    'bower_components/angular/angular.min.js',
    'assets/js/app.js',
    'assets/js/*.js'
  ],
  buildDest: 'public'
};

gulp.task('build-scripts', function() {
  return es.concat(
    gulp.src(paths.coffeeSrc)
      .pipe(coffee({bare: true}).on('error', gutil.log))
      .pipe(gulp.dest(paths.coffeeDest)),
    gulp.src(paths.buildScriptsSrc)
      .pipe(uglify())
      .pipe(concat('app.min.js'))
      .pipe(gulp.dest(paths.buildDest))
    );
});