On July 21, 2026, Jack Dorsey announced on X that Block — the parent company of Square, Cash App, Afterpay, and Tidal — has open-sourced Buzz, a workspace that puts team chat, AI agents, and Git hosting in one place. His positioning was carefully worded: “model-agnostic, decentralized, self-sovereign, and open source.” His motivation was less diplomatic: Buzz was “built to reduce our dependency on Slack and GitHub.”
The same day, the block/buzz repository shipped v0.4.21 desktop builds for macOS, Windows, and Linux under the Apache 2.0 license. The repo’s self-description runs exactly one line: “A hive mind communication platform.” TechCrunch’s read is that Buzz challenges Slack and GitHub at the same time — the chat window contains your human colleagues, your AI agents, and the code and workflows of the same project.
One Open Workspace Against Slack Plus GitHub
The chat half of Buzz is feature-complete on the basics: channels, threads, direct messages, shared canvases, media, search, an audit log, and a desktop app, with workflows defined in YAML. What makes it unusual is the identity model. Employees, AI agents, conversations, and code repositories all sit behind one identity system: the same key pairs, channel memberships, and audit trails apply to humans and agents alike.
That has a practical consequence. “Who said what” and “who changed what” live on the same record from day one, instead of being scattered across a chat history and a version control system that never talk to each other.
Architecture: Everything Is a Signed Event
Under the hood, Buzz runs on a self-hostable Nostr relay. Every message, reaction, workflow step, code event, and approval is stored as a cryptographically signed event. Humans and agents do not merely share an interface; they share one event format and one identity structure.
The word “decentralized” deserves an asterisk, though. As RuntimeWire points out, the relay inside each deployment is still centralized — there is no peer-to-peer event exchange, gossip layer, or replication between relays. What “self-sovereign” means here is that you own and host the whole system, not that deployments federate the way social networks do. For enterprises, the load-bearing part is simpler: data and identity stay on infrastructure you control. That alone is a reason to adopt.
Agents Are Members, Not Plugins
AI agents in Buzz are not traditional bots. They are workspace members: they can search discussions, open repositories, submit patches, review code, run workflows, edit canvases, and even create channels. The product ships with an agent-oriented CLI plus ready-made harnesses for Goose, Codex, and Claude Code, keeping the choice of model separate from the workspace itself. Swap the model without swapping the tool — for teams wary of single-vendor lock-in, that is a concrete escape hatch.
A Feature Branch Is a Channel
The Git hosting side is still at the spec stage, but the direction is written down. The built-in software forge uses standard Git Smart HTTP, and a feature branch can become its own channel: patches, CI results, code reviews, and merge decisions live in one record that shares a search index with discussions and workflow history. The design idea is “conversation as the development record.” If it works, the ritual of pasting GitHub links into Slack threads and then excavating context later simply disappears from the process.
Why Block Built Its Own
The why is spelled out in “From Hierarchy to Intelligence,” an essay Dorsey co-wrote with Sequoia’s Roelof Botha: AI should change how organizations coordinate, not act as a productivity add-on. Block’s stated assignment for Buzz is to “replace portions of chat, code hosting, workflow automation, project search and agent orchestration with one event system.”
Similar experiments are appearing in parallel. Paradigm CTO Georgios Konstantopoulos open-sourced Centaur, a “virtual employee” that lives inside Slack or behind an API. His argument: “There is a lot of room for improvement for agents that live in Slack.” The overlap is telling. Once agents became the primary workers inside chat tools, the tool itself started to look like the constraint.
Reality Check: Not Ready for Migration
The sober notes first. Block’s own documentation labels Buzz unfinished: mobile clients and push notifications are missing, workflow approval gates lack a completed execution path, and no pricing or adoption figures have been published. TechCrunch’s advice is pragmatic — it is early, and teams should not migrate yet.
But the signal is clear enough. When chat, agents, and version control start being designed as one thing, the existing collaboration stack has to re-answer an old question: why three systems?
Sources
- Jack Dorsey is taking on Slack with Buzz — TechCrunch
- Jack Dorsey, Block launch Buzz — RuntimeWire
- block/buzz on GitHub
AI-assisted summary compiled from the sources above, reviewed by a human before publishing.