gulpfile.js

var gulp = require('gulp');
var babel = require('gulp-babel');
var concat = require('gulp-concat');
var watch = require('gulp-watch');
var batch = require('gulp-batch');
var plumber = require('gulp-plumber');
var less = require('gulp-less');

gulp.task('server-es6', function () {
    return gulp.src('server/**/*.es6')
        .pipe(babel())
        .pipe(gulp.dest('server/_compiled'));
});

gulp.task('server-es6-watch', function () {
    return gulp.src('server/**/*.es6')
        .pipe(watch('server/**/*.es6'))
        .pipe(plumber())
        .pipe(babel())
        .pipe(plumber.stop())
        .pipe(gulp.dest('server/_compiled'));
});

gulp.task('client-es6', function () {
    return gulp.src('www/**/*.es6')
        .pipe(babel())
        .pipe(gulp.dest('www/_js'));
});

gulp.task('client-es6-watch', function () {
    return gulp.src('www/**/*.es6')
        .pipe(watch('www/**/*.es6'))
        .pipe(plumber())
        .pipe(babel())
        .pipe(plumber.stop())
        .pipe(gulp.dest('www/_js'));
});

gulp.task('less', function() {
    return gulp.src('www/styles/compiled.less')
        .pipe(less())
        .pipe(gulp.dest('www/styles'));
});

gulp.task('less-watch', function() {
    return watch('www/**/*.less', batch(function(events, done) {
        gulp.start('less', done)
    }));
});


gulp.task('default', ['server-es6', 'client-es6', 'less']);
gulp.task('watch', ['server-es6-watch', 'client-es6-watch', 'less-watch']);