[freerk]

Besides of open source software development I'd propose envolvment in Wikipedia and OpenStreetMap. Both are kind of welcoming communities where you can easily spent a full time equivalent of work in. In most bigger cities in the world there are (used to be before Covid) regular meetups in real live and it really feels as a useful service to the world or local community. Or maybe local wireless communication networks are a thing in your area (like Freifunk)?