Account is free, minimum data (nick and mail, if you want, use an disposable one), well, also Lemmy need an account like almost any other service you use. The account is not shared, but with account you can customize it with plug ins and for an API. Otherwise you can selfhost it, but than you don't have the power of the supercomputer from the swiss datacenter, the same used by the LHC of the CERN, but only the server you use to host it. It don't store previous chats if you don't want, otherwise only stored in your HD.

Webbkoll test