Problems with Composer and Laravel 5.0 on Mac El Capitan

I'm having the following error, after running a command to install a versioned project.

Script php artisan clear-compiled handling the pre-update-cmd event returned with an error

[RuntimeException]
  Error Output: PHP Fatal error: Class 'Illuminate \ Foundation \ Application' n
  ot found in [PRINT_PREP] /bootstrap/app.php on line
  14

Composer file:

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "laravel/framework": "5.0.*",
        "pagarme/pagarme-php": "dev-master",
        "guzzlehttp/guzzle": "~5.0",
        "lucadegasperi/oauth2-server-laravel": "~4.0"
    },
    "require-dev": {
        "phpunit/phpunit": "~4.0",
        "phpspec/phpspec": "~2.1",
        "barryvdh/laravel-debugbar": "^2.0"
    },
    "autoload": {
        "classmap": [
            "database"
        ],
        "psr-4": {
            "App\": "app/"
        }
    },
    "autoload-dev": {
        "classmap": [
            "tests/TestCase.php"
        ]
    },
    "scripts": {
        "post-install-cmd": [
            "php artisan clear-compiled",
            "php artisan optimize"
        ],
        "post-update-cmd": [
            "php artisan optimize"
        ],
        "pre-update-cmd": [
            "php artisan clear-compiled"
        ],
        "post-create-project-cmd": [
            "php -r \"copy('.env.example', '.env');\"",
            "php artisan key:generate"
        ]
    },
    "config": {
        "preferred-install": "dist"
    }
}