Gulp File for simple js project

gulpfile.js

var gulp = require('gulp');
var browserSync = require('browser-sync').create();

var deployPath = 'dist';

gulp.task('default', ['build']);

gulp.task('build', ['js', 'css']);
gulp.task('watch', function () {
    gulp.watch(['src/**'], ['js']);
    gulp.watch(['less/**'], ['css']);
});

gulp.task('serve', ['build', 'watch'], function () {
    var modRewrite = require('connect-modrewrite');
    var header = require('connect-header');

    browserSync.init({
        open: false,
        https: false,
        server: {
            baseDir: deployPath,
            middleware: [
                modRewrite([
                    // rewrite eg. "index" to "index.html"
                    '^(.*)/([^\.\/]+)$ $1/$2.html'
                ]),
                header({
                    // these should be the same in the _headers file
                    'X-UA-Compatible': 'IE=Edge',
                    'X-XSS-Protection': '1; mode=block'
                })
            ]
        }
    });
});

gulp.task('js', function () {
    var browserify = require('browserify');
    var source = require('vinyl-source-stream');
    var buffer = require('vinyl-buffer');
    var uglify = require('gulp-uglify');
    var sourcemaps = require('gulp-sourcemaps');
    var gutil = require('gulp-util');

    return browserify({entries: 'src/main.js', debug: true})
        .transform("babelify", {presets: ["es2015"]})
        .transform("ractivate")
        .transform("require-globify")
        .bundle()
        .pipe(source('app.js'))
        .pipe(buffer())
        .pipe(sourcemaps.init({loadMaps: true}))
        .pipe(uglify())
        .on('error', gutil.log)
        .pipe(sourcemaps.write('./'))
        .pipe(gulp.dest(deployPath))
        .pipe(browserSync.stream())
});

gulp.task('css', function () {
    var sourcemaps = require('gulp-sourcemaps');
    var concat = require('gulp-concat');
    var less = require('gulp-less');
    var autoprefixer = require('gulp-autoprefixer');
    var clean = require('gulp-clean-css');

    return gulp.src(['less/**.less'])
        .pipe(sourcemaps.init())
        .pipe(less({paths: ['.', 'less']}))
        .pipe(concat('app.css'))
        .pipe(autoprefixer({browsers: ['> 0.2% in DE', 'last 2 versions', 'Firefox ESR', 'not IE <= 11']}))
        //.pipe(clean())
        .pipe(sourcemaps.write('./'))
        .pipe(gulp.dest(deployPath))
        .pipe(browserSync.stream())
});

package.json

{
  "name": "project-name",
  "version": "1.0.0",
  "description": "",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "devDependencies": {
    "babel-preset-es2015": "^6.14.0",
    "babelify": "^7.3.0",
    "browser-sync": "^2.15.0",
    "browserify": "^13.1.0",
    "connect-header": "0.0.5",
    "connect-modrewrite": "^0.9.0",
    "gulp": "^3.9.1",
    "gulp-autoprefixer": "^3.1.1",
    "gulp-clean-css": "^2.0.12",
    "gulp-concat": "^2.6.0",
    "gulp-less": "^3.1.0",
    "gulp-sourcemaps": "^1.6.0",
    "gulp-uglify": "^2.0.0",
    "ractivate": "^0.2.0",
    "require-globify": "^1.4.1",
    "vinyl-buffer": "^1.0.0",
    "vinyl-source-stream": "^1.1.0"
  },
  "dependencies": {
    "normalize.css": "^4.2.0"
  }
}