XMPP is also a publishing platform.

The largest HTML-based platforms to utilize Atom Over XMPP are Libervia and Movim, and I also maintain a couple of projects that are called Blasta and Rivista.

Resources:

• https://xmpp.org/extensions/xep-0277.xml
• https://xmpp.org/extensions/xep-0472.xml
• https://datatracker.ietf.org/meeting/66/materials/slides-66-atompub-1.pdf

Projects:

• https://libervia.org
• https://movim.eu
• https://blasta.woodpeckersnest.eu
• https://git.xmpp-it.net/sch/Rivista

As XMPP clients and servers are offered separately and all support standards that are specified by the XSF, the maintenance costs are low.