Start processing less files with this Gulp file! Also supports minified CSS and LiveReload watching.

gulpfile.js

// Run "npm init" and fill out the wizard
// Then run the following to install all dependancies:
// npm install gulp gulp-util gulp-plumber gulp-less gulp-cssmin gulp-concat gulp-rename gulp-livereload

// Include gulp
var gulp = require('gulp'); 

// Include Our Plugins
var gutil  = require('gulp-util');
var plumber = require('gulp-plumber');
var less = require('gulp-less');
var cssmin = require('gulp-cssmin');
var concat = require('gulp-concat');
var rename = require('gulp-rename');
var livereload = require('gulp-livereload');

// LESS css task
gulp.task('less', function() {
    return gulp.src('assets/stylesheets/style.less')  // only compile the entry file
        .pipe(plumber(function(error) {
            gutil.log(gutil.colors.red(error.message));
            gutil.beep();
            this.emit('end');
        }))
        .pipe(less({
            paths: ['assets/stylesheets/']
        }))
        .pipe(rename('layout.css'))
        .pipe(gulp.dest('assets/stylesheets/'))
        .pipe(cssmin())
        .pipe(rename({suffix: '.min'}))// 
        .pipe(gulp.dest('assets/stylesheets/'));
});

// Watch Files For Changes
gulp.task('watch', function() {
    gulp.watch('assets/stylesheets/*.less', ['less']);
    livereload.listen();
    gulp.watch('assets/stylesheets/*').on('change', livereload.changed);
    gulp.watch('*').on('change', livereload.changed);
});

// Default Task
gulp.task('default', ['less', 'watch']);