--- /dev/null
+Yaml Component
+==============
+
+The Yaml component loads and dumps YAML files.
+
+This is a COPY of symfony/yaml re-namespaced to Drush\Config\Yaml. This is
+here so that Drush can parse its yaml config and aliasfiles prior to autoloading
+any Symfony packages. This helps avoid dependency conflicts when the global
+Drush includes the autoload file from Drupal.
+
+DO NOT USE THESE CLASSES OUTSIDE OF PREFLIGHT. Instead, use symfony/yaml.
+
+Resources
+---------
+
+ * [Documentation](https://symfony.com/doc/current/components/yaml/index.html)
+ * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+ * [Report issues](https://github.com/symfony/symfony/issues) and
+ [send Pull Requests](https://github.com/symfony/symfony/pulls)
+ in the [main Symfony repository](https://github.com/symfony/symfony)