laravel - baixar arquivos grandes

exemplo.php

use Laravel\Lumen\Http\ResponseFactory; // para lumen
use Illuminate\Http\Response; // para laravel

ResponseFactory::macro('baixarStream', function ($stream) {
    return response()->stream(function () use ($stream) {
        while (!feof($stream)) {
            echo fread($stream, 1024);
        }
        fclose($stream);
    });
});

// exemplo de uso
return response()->baixarStream(Storage::readStream('arquivo.pdf'));