New and Improved Gulp for Front-End Development

gulpfile.js

var path = require('path');  
var gulp = require('gulp');  
var gutil = require('gulp-util');  
var clean = require('gulp-clean');  
var concat = require('gulp-concat');  
var uglify = require('gulp-uglify');  
var rename = require('gulp-rename');  
var filesize = require('gulp-filesize');  
var less = require('gulp-less');  
var changed = require('gulp-changed');  
var watch = require('gulp-watch');

gulp.task('clean', function () {  
  gulp.src('build', {read: false})
    .pipe(clean());
});

gulp.task('vendor', function() {  
  gulp.src('vendor/*.js')
    .pipe(concat('vendor.js'))
    .pipe(gulp.dest('build'))
    .pipe(filesize())
    .pipe(uglify())
    .pipe(rename('vendor.min.js`))
    .pipe(gulp.dest('build'))
    .pipe(filesize())
    .on('error', gutil.log)
});

gulp.task('css', function () {  
  gulp.src('less/**/*.less')
    .pipe(changed('build/css'))
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(gulp.dest('build/css'))
    .on('error', gutil.log);
});

gulp.task('css:watch', function () {  
  watch({
    glob: 'less/**/*.less',
    emit: 'one',
    emitOnGlob: false
  }, function(files) {
    return files
      .pipe(less({
        paths: [ path.join(__dirname, 'less', 'includes') ]
      }))
      .pipe(gulp.dest('build/css'))
      .on('error', gutil.log);
  });
});