Strapi is a Node.js-based headless content management system. It has a slick admin dashboard that is quick and enjoyable to use as a content creator.
Strapi has a well-documented plugin development API, making it easier for developers to inject UI elements into the default CMS to extend functionality, for example, generating PDF's from content.
I use Strapi to build content-focused websites and internal tools, including my own invoice management software.
One of the benefits to Strapi over more traditional PHP-based content management systems is that it can be hosted on ephemeral infrastructure-as-a-service platforms.