Jack Dorsey announced Buzz, an open-source group chat platform built by Block, on July 21, 2026. The product is designed to compete with Slack and GitHub, and it makes one defining design choice: human users and their AI agents share the same conversations rather than working through separate channels or API connections. (TechCrunch)

Dorsey described Buzz on X as "model-agnostic, decentralized, self-sovereign, and open source." His X/Twitter profile bio calls it "an open-source workspace for humans and AI agents, on a relay you own." (TechCrunch)

The codebase is available on GitHub, and a free desktop app can be downloaded for macOS, Windows, and Linux. The product's website is hosted at buzz.xyz. (TechCrunch)

The project is candid about its maturity. Buzz acknowledges it is in its "early stages" and is not yet ready for teams to fully migrate from existing platforms. That places it closer to an early public build than a production-ready Slack replacement on day one. (TechCrunch)

Block, the company behind Buzz, is best known for Square, Cash App, Afterpay, and Tidal. Buzz is a step away from that portfolio's fintech and commerce focus and into developer-facing collaboration tools. (TechCrunch)

Dorsey is entering a landscape where others are already thinking along similar architectural lines. Paradigm partner and CTO Georgios Konstantopoulos recently unveiled Centaur, an open-source product described as a "virtual employee" that runs inside Slack or via an API. The overlap is clear: both projects assume that AI agents will be first-class participants in team workflows, not background tools called up through separate interfaces. (TechCrunch)

The architectural choices Dorsey has flagged deserve closer attention. "Model-agnostic" means the platform does not lock users into a single AI model provider, so a team could switch between, say, OpenAI, Anthropic, or an open-source model without changing tools. "Decentralized" and "self-sovereign," combined with the "relay you own" framing in his bio, suggest an architecture where message routing and data storage sit with the user or their organization rather than with a central platform operator. Think of it as running your own mail server instead of relying on Gmail: you control the infrastructure and the data, but you also take on the responsibility of maintaining it. For teams evaluating where their conversation data lives and who controls how long it is kept, those are structurally different promises than what Slack or Microsoft Teams offer today.

The open-source approach also matters for adoption. A publicly available codebase on GitHub lets security teams audit the product before deploying it, lets infrastructure teams self-host if the architecture supports it, and lets developers extend the platform through contributions rather than relying on a vendor-controlled plugin marketplace. Whether that translates into a viable ecosystem depends on how actively Block maintains the repository and whether third-party contributors get involved.

Dorsey's competitive positioning spans two distinct product categories. Slack owns synchronous team communication; GitHub owns asynchronous code collaboration and, increasingly, broader project management. A single platform attempting to address both, while also introducing agent-native chat as a core feature rather than a bolt-on integration, is an ambitious scope. The early-stages caveat suggests Block is aware of the gap between vision and current capability.

The broader context here is that what is genuinely new is not group chat, open-source collaboration tools, or AI agents operating in enterprise environments individually. It is the assertion that all three belong in the same conversation layer, with the user owning the relay. If that architecture proves workable, the implications go beyond displacing existing tools. They touch on how teams govern agent behavior, audit messages initiated by agents, and maintain control over their data in workflows that are increasingly mediated by AI models none of the participants fully control.

The project is available now for evaluation. Whether teams adopt it at scale will depend on factors Buzz has not yet demonstrated: enterprise-grade reliability, a mature access-control model, and the kind of integration ecosystem that took Slack years to build. The code is on GitHub, the desktop apps are free, and Dorsey has set the architectural terms clearly. The rest is execution.