gulp with es6

gulpfile.babel.js

import gulp from 'gulp';
import stylus from 'gulp-stylus';
import uglify from 'gulp-uglify';
import imagemin from 'gulp-imagemin';

gulp.task('css', () => {
  return gulp.src('./src/css/*.styl')
    .pipe(stylus({
      compress: true
    }))
    .pipe(gulp.dest('./build/css'));
});

gulp.task('js', () => {
  return gulp.src('./src/js/*.js')
    .pipe(uglify())
    .pipe(gulp.dest('./build/js'));
});

gulp.task('img', () => {
  return gulp.src('./src/img/*')
    .pipe(imagemin({
        progressive: true,
        svgoPlugins: [{removeViewBox: false}],
    }))
    .pipe(gulp.dest('./build/img'));
});

gulp.task('default', ['css', 'js', 'img'], () => {} );