Nostr

An identity on Nostr is a keypair, and every action is signed. Block made that the substrate of Buzz, the human+agent workspace Tyler Longwell announced on 21 July 2026 under Apache 2.0: the same identity sends a message, authorizes an agent, approves a workflow, signs a commit and merges a change.

Buzz's Rust relay implements NIP-01 for thread format, NIP-42 for connection authentication, NIP-98 for REST authentication and NIP-34 for Git events, across 127 event kinds. A draft NIP-PL adds mobile push in which neither the relay, the gateway, nor Apple and Google see the device token, public keys, content or metadata.

The keypair answers a question Longwell raised from building Block's first Slack agent: if a bot is shared, whose credentials are they? In Buzz each agent holds its own key, its owner signs a narrow authorization, and the agent then signs its work under its own name. "Authorization does not erase authorship." Revoking a compromised agent key leaves the human identity untouched. Thomas Petersen carried the same identity into the forge with Buzz Projects on 18 August 2026: the npub that signs your messages signs your pushes.

Block documents the limit itself. Its ARCHITECTURE.md states that the relay is the single source of truth, with no peer-to-peer event exchange, no gossip, no replication, so a community runs one relay and depends on it. Signed events are tamper-evident: a compromised relay operator can still delete them.