A lot of messaging systems try to reinvent the email system but many (signal, matrix, xmpp) took over one key traditional design which we actually dropped while retaining SMTP/IMAP compatibility: server-controlled identities.
With #chatmail user identities are cryptographic and reside on end user devices only. Servers are only message relays and have no control over identities or chats, only perform fast message routing. See this fosdem talk by one of our lead developers
Delta Chat
npub17g…ynrxn
2026-02-04 21:47:38 UTC
Author Public Key
npub17gpd02zrcswhzlwa7m9sz0tw76ylgncjy9xxa4ppkjzqyzhvygyqvynrxnSeen on
wss://relay.momostr.pinkPublished at
2026-02-04 21:47:38 UTCEvent JSON
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"kind": 1,
"tags": [
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"content": "A lot of messaging systems try to reinvent the email system but many (signal, matrix, xmpp) took over one key traditional design which we actually dropped while retaining SMTP/IMAP compatibility: server-controlled identities.\n\nWith #chatmail user identities are cryptographic and reside on end user devices only. Servers are only message relays and have no control over identities or chats, only perform fast message routing. See this fosdem talk by one of our lead developers https://mirror.cyberbits.eu/fosdem/2026/ud2218a/3F9VTU-deltachat-chatmail-relays-multi-transport.av1.webm",
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}