At Assemblée Virtuelle, we work since 2 years + now on https://github.com/assemblee-virtuelle/semapps - DB is Jenna Fuseki and Middleware is developed using JS (Molecular).
You can find some doc here, especially regarding AP : ActivityPub | SemApps
Also, we have identified GO as a very interesting perspective for it’s reliability for intensive network and parallele execution. Beside it can run on every device (mobile also).
We would be delighted to talk together in order to share our work and hear about what you do as well (1 hour call maybe, if you like ?)