January 1, 2022
Convert a Custom Upstream to Integrated Composer - Learn how to convert a non-Composer-managed Drupal 8 site to Integrated Composer while on Drupal 8. The process is similar to the Upgrade Pantheon Drupal 8 Sites to Drupal 9 With Integrated Composer guide, except that you will stay on Drupal 8 with some special considerations for Custom Upstreams, and can defer the Drupal 9 upgrade to later. Refer to the documentation for more information.