gulpfile.js

// Load plugins
var gulp = require('gulp'),
    sass = require('gulp-ruby-sass'),
    // autoprefixer = require('gulp-autoprefixer'),
    minifycss = require('gulp-minify-css'),
    jshint = require('gulp-jshint'),
    uglify = require('gulp-uglify'),
    imagemin = require('gulp-imagemin'),
    rename = require('gulp-rename'),
    concat = require('gulp-concat'),
    notify = require('gulp-notify'),
    cache = require('gulp-cache'),
    livereload = require('gulp-livereload'),
    del = require('del');

// Styles
gulp.task('styles', function() {
  return sass('_sass/style.scss', { style: 'expanded' })
    // .pipe(autoprefixer('last 2 version'))
    .pipe(gulp.dest('dist/styles'))
    .pipe(rename({ suffix: '.min' }))
    .pipe(minifycss())
    .pipe(gulp.dest('dist/styles'))
    .pipe(notify({ message: 'Styles task complete' }));
});

// Scripts
gulp.task('scripts', function() {
  return gulp.src(['js/jquery-2.1.4.min.js', 'js/howler.min.js', 'js/notes.js', 'js/script.js'])
    // .pipe(jshint('.jshintrc'))
    // .pipe(jshint.reporter('default'))
    .pipe(concat('main.js'))
    .pipe(gulp.dest('dist/scripts'))
    .pipe(rename({ suffix: '.min' }))
    .pipe(uglify())
    .pipe(gulp.dest('dist/scripts'))
    .pipe(notify({ message: 'Scripts task complete' }));
});

// Images
gulp.task('images', function() {
  return gulp.src('images/**/*')
    .pipe(cache(imagemin({ optimizationLevel: 3, progressive: true, interlaced: true })))
    .pipe(gulp.dest('dist/images'))
    .pipe(notify({ message: 'Images task complete' }));
});

// Clean
gulp.task('clean', function(cb) {
    // del(['dist/assets/css', 'dist/assets/js', 'dist/assets/img'], cb)
    del(['dist/'], cb)
});

// Default task
gulp.task('default', ['clean'], function() {
    // gulp.start('styles', 'scripts', 'images');
    gulp.start('styles', 'scripts');
});

// Watch
gulp.task('watch', function() {

  // Watch .scss files
  gulp.watch('_sass/*.scss', ['styles']);

  // Watch .js files
  gulp.watch('js/*.js', ['scripts']);

  // Watch image files
  // gulp.watch('src/images/**/*', ['images']);

  // Create LiveReload server
  livereload.listen();

  // Watch any files in dist/, reload on change
  gulp.watch(['dist/**', 'index.html']).on('change', livereload.changed);

});