Using Elixir outside of Laravel

gulpfile.js

var elixir = require('laravel-elixir');

config.assetsPath = 'app';
config.publicPath = 'dist';

elixir(function(mix) {
    // your mixes here
	mix.less('style.less').scripts('main.js');
});

package.json

{
  "private": true,
  "devDependencies": {
    "gulp": "^3.8.8"
  },
  "dependencies": {
    "laravel-elixir": "^3.0.0"
  }
}