Specification / v1

The Shum protocol

How identity, messages and delivery work in Shum. Everything you need to write a compatible client.

Current implementation

Draft. The first stable version is in progress.

How the protocol works

In Shum, a profile is a set of keys on a device. Every message is signed and sealed in an envelope that only the recipient can open. The envelope is the same over Bluetooth and Nostr; only the delivery differs.

Shum ID: An identifier derived from the public Noise key
Envelope: Data encrypted for the recipient
Transport: Bluetooth nearby or Nostr over the internet

Specification v1

Protocol repository on GitHub

00Overview and terms 01Keys and identity 02Contact card and invitations 03Message envelope 04Packet types 05Acceptance and merge rules 06Bluetooth transport 07Nostr transport 08Push server API 09On-device storage 10Multiple devices 11Profile relays and relay networks 12First stable version

Client compatibility

Every client is checked against the same test vectors: signatures, envelopes, merge rules, transports. Any format change gets its own version number.

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