For a long time, I ve wanted a way to do realtime family/friend location sharing with e2ee.So I finally built one!Some details:- The protocol uses a Signal-style double-ratchet (though with some differences) for PFS/PCS (but no PQ, a la SPQR)- For simplicity and privacy, there s no persistent user identifier--just sessions. If you lose your phone, you and your friends have to re-pair.- Message sharing uses ephemeral mailbox tokens to make social network/metadata analysis difficult.Technical details (and links to Github) here: https://where.af0.net/technical.Thrilled to get feedback!