Laravel Service Container Automatic Injection

php artisan make:class Services/Calculator

app/Services/Calculator.php

<?php

namespace App\Services;

class Calculator
{
    public function add(array $numbers): int
    {
        return array_sum($numbers);
    }
}

routes/web.php

<?php

use App\Services\Calculator;
use Illuminate\Support\Facades\Route;

Route::get('/', function (Calculator $calculator) {
    return $calculator->add(range(1, 100));
});