Gulp setup for Drupal 8 (Acquia DevDesktop, SASS, ES6, Browser Sync)

gulpfile.js

var gulp = require('gulp');
var browserSync = require('browser-sync');
var sass = require('gulp-sass');
var prefix = require('gulp-autoprefixer');
var concat = require('gulp-concat');
var babel = require('gulp-babel');
var cp = require('child_process');

/**
 * Launch the Server
 */
gulp.task('browser-sync', ['sass', 'scripts'], function() {
  browserSync.init({
    open: 'external',
    host: 'localhost',
    proxy: "http://localhost:8083",
    port: 8083
  });
});

/**
 * @task sass
 * Compile files from scss
 */
gulp.task('sass', function () {
  return gulp.src('src/scss/styles.scss')
    .pipe(sass())
    .pipe(prefix(['last 3 versions', '> 1%', 'ie 8'], { cascade: true }))
    .pipe(gulp.dest('assets/css'))
    .pipe(browserSync.reload({stream:true}))
});

/**
 * @task scripts
 * Compile files from js
 */
gulp.task('scripts', function() {
  return gulp.src(['src/js/*.js', '_js/custom.js'])
    .pipe(babel({
      presets: ['es2015']
    }))
    .pipe(concat('scripts.js'))
    .pipe(gulp.dest('js'))
    .pipe(browserSync.reload({stream:true}))
});

/**
 * @task clearcache
 * Clear all caches
 */
gulp.task('clearcache', function(done) {
  return cp.spawn('drush', ['cache-rebuild'], {stdio: 'inherit'})
    .on('close', done);
});

/**
 * @task reload
 * Refresh the page after clearing cache
 */
gulp.task('reload', ['clearcache'], function () {
  browserSync.reload();
});

/**
 * @task watch
 * Watch scss files for changes & recompile
 * Clear cache when Drupal related files are changed
 */
gulp.task('watch', function () {
  gulp.watch(['src/scss/*.scss', 'src/scss/**/*.scss'], ['sass']);
  gulp.watch(['src/js/*.js'], ['scripts']);
  gulp.watch(['templates/*.html.twig', '**/*.yml'], ['reload']);
});

/**
 * Default task, running just `gulp` will
 * compile Sass files, launch BrowserSync, watch files.
 */
gulp.task('default', ['browser-sync', 'watch']);

package.json

{
  "name": "myfi",
  "version": "1.0.0",
  "description": "",
  "main": "gulpfile.js",
  "devDependencies": {
    "babel-preset-es2015": "^6.24.1",
    "browser-sync": "^2.18.13",
    "gulp": "^3.9.1",
    "gulp-autoprefixer": "^4.0.0",
    "gulp-babel": "^6.1.2",
    "gulp-concat": "^2.6.1",
    "gulp-sass": "^3.1.0",
    "normalize.css": "^8.0.0"
  },
  "scripts": {
    "postinstall": "find node_modules/ -name '*.info' -type f -delete"
  },
  "author": "rgreen <rg@ie.com.au>",
  "license": "ISC"
}