Buzz
Buzz is Block's open-source workspace where teammates and AI agents share the same channels, threads and git projects, with every message, review and pull request written as a signed Nostr event on a relay you can host yourself.
Pros
- Genuinely open source under Apache 2.0 with the full stack on GitHub (github.com/block/buzz, 31.7k stars), so a team can run the whole workspace on its own infrastructure via docker-compose or a one-click Railway deploy and pay nothing in licence fees. Every human and every agent gets its own Nostr keypair, which means messages, code reviews and CI triggers are cryptographically signed into one append-only log rather than trusted to a central account system, and the protocol layer is standard Nostr (NIP-01, NIP-42 auth, NIP-34 for git events) rather than a proprietary format. Agents connect over the open Agent Client Protocol through the buzz-acp harness, so goose, Codex and Claude Code all work without a bespoke integration, and buzz-cli exposes the workspace as JSON in, JSON out for direct LLM tool calls. Desktop builds for macOS, Linux and Windows ship on a fast cadence, with desktop-v0.5.20 dated 26 August 2026.
Cons
- The site labels this a developer preview and the version numbering agrees, so it is early software rather than something to bet a company's communications on today
- the Windows installer in the v0.5.20 release is still published as alpha and unsigned, and the Flutter mobile apps are described as in development rather than shipped. Self-hosting is not optional in practice, which means running a Nostr relay and a Docker stack and carrying the ops burden yourself, and Nostr key management lands squarely on the operator: a leaked or lost private key is a real and largely unrecoverable problem in a system where identity is the key. There is no published pricing or generally available managed tier, and the enterprise version built for company-wide access, support and agent management is waitlist-only, so a team wanting a supported product has no purchase path right now.
Cost
Free and open source under Apache 2.0, self-hosted, with no licence cost and no published subscription price. Running it means paying only for your own server, relay and whatever models your agents call. An enterprise edition with company-wide access, support and agent management is announced as waitlist-only, and no pricing for it has been published.
Verdict
Best for engineering teams already running coding agents who want chat, planning and git in one auditable place and are comfortable operating their own relay; anyone needing a supported, stable, buy-it-today workspace should wait for the enterprise edition to leave the waitlist.
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