Compare Contenta vs. Pimcore
Contenta is a Drupal 8 distribution that aims to provide a headless, decoupled shell for Drupal 8.
Pimcore is a CMS whose development started in 2009. Originally the Content Management System was built on the Zend PHP Framework, but the system will switch to the Symfony full stack framework.
CMSes vailable for comparison: BackBee, Bolt CMS, Concrete5, Contenta, Contentful, Cosmic.js, Craft CMS, Drupal 8, eZ Platform, Fork CMS, GraphCMS, Grav, Jarves, Joomla!, Kunstmaan, October CMS, Open Orchestra, Pagekit, Pimcore, PyroCMS 3, Reservoir, Spress, Sulu CMS, Symfony CMF, Symphony CMS