private function findPackages($slugs)
    {
        $packages = [];

        foreach ($slugs as $package_slug) {
            $packageDir = $this->workingDir . '/vendor/' . $package_slug .'/';

            if (! is_dir($packageDir)) {
                continue;
            }

            $package = new Package($packageDir);
            $package->findAutoloaders();

            $config = json_decode(file_get_contents($packageDir . 'composer.json'));

            $dependencies = [];
            if (isset($config->require)) {
                $dependencies = array_keys((array)$config->require);
            }

            $package->dependencies = $this->findPackages($dependencies);
            $packages[] = $package;
        }

        return $packages;
    }