agumonkey

What else is there in this field ?

jarofgreen
If you mean the field of people organising events on open source decentralised software, I think there is:

* https://framagit.org/les/gancio

* https://github.com/lowercasename/gathio

* https://github.com/GetTogetherComm/GetTogether

* https://github.com/hometown-fork/hometown Mastodon fork with basic event stuff

(This is not to take away from Mobilizon - congrats to them!)