Drupal 8 comes with a Proudly Built Elsewhere attitude. There has been an effort made to use more components created by the PHP community at large and other communities. Drupal 8 is built with Symfony. It includes Twig as its templating system, the provided WYSIWYG editor as its CKEditor, and PHPUnit for testing.
How does Drupal 8 promote using libraries made elsewhere? The new asset management system in Drupal 8 makes it easier to use frontend libraries. Drupal implements PSR-0 and PSR-4 from the PHP Framework Interoperability Group (PHP-FIG), and PHP Standards Recommendations (PSRs) are suggested standards used to increase interoperability between PHP applications. This has streamlined integrating third-party PHP libraries.
Both areas will be constantly improved with each minor release of Drupal 8. These areas will be mentioned throughout the chapter.
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