Electrum servers

Biscuit doesn’t download the Bitcoin or Litecoin blockchain. It asks an Electrum server about your addresses: their payments, their balance, and the current fees. It’s fast, but the server learns which addresses you ask about.

Public servers

By default, Biscuit uses well-known public servers, with encrypted (TLS) connections, and moves to another one if a server fails. In Tor mode it reaches them through Tor, so they don’t see your IP address. They still see the addresses: a server could guess they belong together.

Your own server

With your own server, no one else learns your addresses. Settings › Network › Bitcoin & Litecoin, then enter it as host:port:

• Any Electrum server works: Electrs, Fulcrum, Electrum Personal Server, on a node of yours, Umbrel or Start9.
• Biscuit then connects only to that server, never to public ones.
• The connection must be encrypted (TLS). A self-signed certificate is accepted and remembered on the first connection; if it changes later, Biscuit refuses it.
• For a .onion address or a server on your local network, an unencrypted tcp://host:port is allowed too.

Leave the field empty to go back to the public servers.