October CMS with Gulp, Less and LiveReload

gulpfile.js

/**
 * Dependencies
 */
 var gulp = require('gulp');
 var glob = require('glob');
 var less = require('gulp-less');
 var gutil = require('gulp-util');
 var plumber = require('gulp-plumber');
 var minifycss = require('gulp-minify-css');
 var autoprefixer = require('gulp-autoprefixer');
 var groupmedia = require('gulp-group-css-media-queries');
 var livereload = require('gulp-livereload');

/**
 * less / CSS processes
 */
 gulp.task('css', function() {

gulp.src('assets/less/theme.less')
        .pipe(plumber({                             // Logs errors and makes a beep
            errorHandler: function (err) {  
                gutil.beep();
                console.log(err);
            }
            }))
        .pipe(less())                               // Compile our less
        .pipe(autoprefixer('last 20 versions'))     // Add browser prefixes
        .pipe(groupmedia())                         // Group media queries
        .pipe(minifycss())                          // Minify
        .pipe(gulp.dest('assets/css'))             // Pipe the output to our css directory
        .pipe(livereload())
        });

/**
 * Watches the file system for changes
 */
 gulp.task('watch', function() {
    gulp.watch([
        'content/*.htm',                            // Watch OctoberCMS .htm files
        'layouts/*.htm',
        'pages/*.htm',
        'partials/*.htm',
        'assets/less/**/*.less'                     // Watch for .less files
        ], ['css']);
    livereload.listen();
    })

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

package.json

{
  "name": "October CMS Demo",
  "version": "1.0.0",
  "description": "Demo Theme",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Tobias Dalhof",
  "license": "ISC",
  "devDependencies": {
    "glob": "^4.3.1",
    "gulp": "^3.8.10",
    "gulp-autoprefixer": "^2.0.0",
    "gulp-group-css-media-queries": "^1.0.0",
    "gulp-less": "^3.1.0",
    "gulp-livereload": "^3.8.1",
    "gulp-minify-css": "^0.3.11",
    "gulp-plumber": "^0.6.6",
    "gulp-util": "^3.0.1"
  }
}

First, you drop the files inside your root theme folder. Then you run npm install and gulp or gulp watch.