Can you host a private lemmy instance, an instance that will not federate with any other instances? Therefore no one from another instance can post, comment or view posts and communities from your instance. Your instance users cannot post, comment, or view communities on other instances

Is there a modern lemmy web ui option out there? lemmy.world and all the other instances I know use a lightweight, basic UI which has its benifits and gives a bit of an old reddit feel.

Can Lemmy federate with these platforms? - Peertube (Video comments) - Mastodon (Tweets/Toots comments) - Plemora (Tweets comments) - Misskey (Tweets comments) - Plume (Blog post comments)