Craft

 Craft  is a commercial PHP/MySQL CMS and eCommerce platform, with both hosted and self-hosted options. See how to get started for installation or check out their documentation.

Craft is available for use under several different licenses, both paid-for and free. The free license notably still includes all localisation and content editing tools, whilst paid licenses introduce team functionality such as multi-user verification and enhanced content moderation tools.

Since the release of version 3.3 Craft has had a dedicated headless mode. That release also saw the introduction of an integrated GraphQL API, though it is currently (as of 2020) only accessible to paid license holders. For free license users, the first-party Elements API plugin offers an easy route to set up a RESTful JSON API.

IndieWeb Examples

 * Matthias on https://matthiasott.com/ since ????-??-??
 * Shane Hudson on https://shanehudson.net/ since September 2014
 * Stephen Bowling on https://stephenbowling.com/
 * uses Craft as a headless CMS on https://theadhocracy.co.uk since 2019

Plugins

 * Webmention plugin for Craft 2: https://github.com/matthiasott/webmention
 * Note that this is not yet compatible with Craft 3
 * User report this plugin is not compatible with the current version (3) of Craft CMS
 * Internet Archive: https://github.com/matthiasott/internetarchive