Jack Dorsey launches Buzz, workplace chat platform for humans and AI agents

Jul 21, 2026

Jack Dorsey's Block has launched Buzz, a free, open-source workplace chat platform challenging Slack and GitHub. Buzz allows humans and AI agents to collaborate as equals, each with a unique cryptographic identity to ensure accountability. Built on the Nostr protocol, it aims to solve AI governance issues but launches as early-stage software into a market dominated by Microsoft Teams and Slack.

Buzz platform launch

▪A free desktop version of Buzz is available for macOS, Windows, and Linux under an Apache 2.0 license.
▪Buzz is positioned as an open-source, decentralized, and model-agnostic challenger to Slack and GitHub.
▪Jack Dorsey's company Block launched Buzz, a workplace chat platform for humans and AI agents, on July 21, 2026.

Cryptographic identity model

▪AI agents in Buzz receive a second cryptographic signature that links them to their human owner, creating a verifiable chain of custody.
▪A Cloud Security Alliance study found that 68% of organizations cannot clearly distinguish between human and AI agent activity in their systems.
▪Every participant in Buzz, whether human or AI, is assigned a unique secp256k1 cryptographic keypair for identity.

Nostr protocol architecture

▪Buzz's 'decentralized' architecture means organizations can run their own private relay; it is not a peer-to-peer system.
▪The self-hosted stack for a Buzz relay requires Docker, Rust 1.88 or later, and Node 24 or later.
▪The Buzz platform is built on Nostr, an open protocol where every action is a signed JSON object, creating a tamper-evident audit log.

Built-in Git hosting

▪Block's internal coding agent, BuilderBot, operates within Buzz and is responsible for about 15% of the company's production code changes.
▪The platform has native support for AI coding agents like Goose, OpenAI's Codex, and Anthropic's Claude Code.
▪Buzz includes a built-in software forge using Git Smart HTTP, allowing teams to host code repositories directly within the platform.

Enterprise messaging market

▪The enterprise messaging market is dominated by Microsoft Teams, with 320 million monthly users, and Slack.
▪Block reported a net loss of $308.7 million in Q1 2026, following a significant workforce reduction.
▪A competing product named Centaur, which integrates into Slack rather than replacing it, was launched on May 21, 2026.

Early-stage limitations

▪The platform's immediate audience is software engineering teams willing to invest in self-hosted infrastructure for managing AI agents.
▪As of its launch at version 0.4.21, Buzz is considered early-stage software with unfinished mobile apps and pending push notifications.