Sum (of an array) validation in Laravel

ValidationServiceProvider.php

<?php

namespace App\Providers;

use Illuminate\Support\Facades\Validator;
use Illuminate\Support\ServiceProvider;
use InvalidArgumentException;

class ValidationServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap the application services.
     *
     * @return void
     */
    public function boot()
    {
        Validator::extend('sum', function ($attribute, $value, $parameters) {
            if (count($parameters) !== 1) {
                throw new InvalidArgumentException('Validation rule sum requires exactly 1 parameter.');
            }

            return array_sum($value) >= $parameters[0];
        });
    }

    /**
     * Register the application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

Great. Thanks a lot!