Drupal is an open-source PHP CMS with first-class support for JSON:API as well as the ability to build a custom GraphQL endpoint by way of an add-on module.
Drupal is a powerful, robust content management system built on object-oriented PHP. Drupal runs websites such as grammy.com, harvard.edu, and millions more.
A standards compliant JSON:API implementation is available out of the box but with anything Drupal you can customise and configure this by adding any number of community created modules.
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