Good. It seems I unconsciously used my own experience. In my country, even having users limit on a platform requires you to register with the state service.
In that case, it doesn’t matter much what you set up. If you just need a chat, Matrix is a good option. Or maybe Mattermost if you need a nice client. There are also several social network platforms in the Fediverse.
Well then, your choices are: 1. Buy a server under a false name 2. Never connect directly to the server or the host’s site. Use proxies for management (preferably proxies in another country). 3. Change keys more often. 4. Reinstall the system on a VPS so that the disk is fully encrypted in case the VPS is seized or management is intercepted. LUKS is the best choice. 5. Don’t keep any logs on the server.
Even with all this, your VPS provider can still reveal the addresses of everyone who connected to the instance, so the most challenging part from a user experience perspective is: none of your users should connect directly to the instance, only through proxies or VPNs on other nodes.
Honestly, it’s much easier to publish an instance on Tor or I2P networks. But in any case, even if the server is published on I2P, follow all the points from the first paragraph.
UPD: honestly, it’s better to put a i2p Floodfill router on a VPS to support the anonymous network within the country. And promote node hosting. This will give much more benefit. Publishing something inside an anonymous network is much less risky than on the internet, though caution must still be exercised.
The first step is to understand what you want exactly. Microblogging like Twitter? A social network like Facebook? A video hosting like YouTube? This depends on a lot. Lemmy communities can’t be closed out of the box, but YouTube for example can be closed to registered users or with a private link.