At Drupal Europe 2018, Dries Buytaert, the founder and lead developer of the Drupal content management system announced that Drupal 9 will be released in 2020. Yesterday, he shared a much detailed timeline for Drupal 9, according to which it is planned to release on June 3, 2020.
One of the biggest dependency of Drupal 8 is Symfony 3 and it is scheduled to reach its end-of-life by November 21. This means that no security bugs in Symfony 3 will be fixed and people have to move to Drupal 9 for better support and security. Going by the plan, the site owners will have at least one year to upgrade from Drupal 8 to Drupal 9.
Drupal 9 will not have a separate code base, rather the team is adding new functionalities in Drupal 8 as backward-compatible code and experimental features. Once they are sure that these features are stable, any old functionalities will be deprecated.
One of the most notable update will be, support for Symfony 4 or 5 in Drupal 9. Since, Symfony 5 is not yet released the scope of its changes will not be clear to the Drupal team. They are focusing on running Drupal 8 with Symfony 4. The final goal is to make Drupal 8 work with Symfony 3, 4 or 5 so that any issues encountered can be fixed before they start requiring Symfony 4 or 5 in Drupal 9.
As Drupal 9 is being build in Drupal 8, this will make things much easier for every stakeholder. Drupal core contributors will just have to remove the deprecated functionalities and upgrade the dependencies. For site owners it will be much easier to upgrade to Drupal 9 than it was to upgrade to Drupal 8.
Dries Buytaert in his post said, “Drupal 9 will simply be the last version of Drupal 8, with its deprecations removed. This means we will not introduce new, backwards-compatibility breaking APIs or features in Drupal 9 except for our dependency updates. As long as modules and themes stay up-to-date with the latest Drupal 8 APIs, the upgrade to Drupal 9 should be easy. Therefore, we believe that a 12- to 18-month upgrade period should suffice.”
You can read the full announcement on Drupal’s website.