a17243d846
## Goal Give operators a way to relieve database pressure in seconds, without restarting relay pods. Today every concurrency limit is an environment variable, so changing one means a rollout. During an incident, that rollout's restart sets off a reconnect storm of its own. ## What changes **Two runtime-tunable caps.** Each is read from an integer feature flag in a new process-wide evaluation context, and re-read every 5 s: | Flag | Caps | Ceiling | |---|---|---| | `buzz.relay.concurrency.history-reads` | subscription-history reads holding a reader connection (the #9132 gate) | the existing `pool − pool/5` share, which keeps readers free for authorization | | `buzz.relay.concurrency.auth` | verified NIP-42 AUTH frames running their database checks | none (unbounded today) | - **Flags can only tighten.** A positive value is clamped to the ceiling. Zero, a negative value, no value, or a provider that never initialized leaves the gate at its ceiling, which is today's behavior. Once LaunchDarkly has delivered values, they stay in force through a later outage, so a cap tightened during an incident survives a provider blip. - **Lowering never cancels admitted work.** A lowered gate admits nothing new until the work in flight falls under the new limit. - **Visibility:** `buzz_concurrency_limit{gate}` reports the applied limit (`0` means no limit), and each change logs a line. **One resizable gate.** `HistoryReadGate` becomes `buzz_db::ConcurrencyGate`, a FIFO semaphore whose limit can move anywhere in `1..=ceiling`: - Lowering it forgets free permits and records any shortfall as debt. - A permit released while there is debt is retired instead of returned. - Raising it repays debt first, then adds permits. All of this, and admission itself, settles against the debt under one lock, so a newer limit always supersedes an older one; there is no background resize task to race. Tokio hands a released permit to a queued waiter before it runs; if that waiter is then cancelled, tokio returns the permit to the semaphore directly, so admission retires any permit it gets while debt is outstanding. The AUTH cap uses the same type. **AUTH shedding.** The permit is taken after signature verification, so only real logins queue for the database checks. The wait is bounded at 2 s. A shed login gets a bare close with no `OK`, exactly like an auth timeout. I chose this from what each client does on main today: - **`OK false`:** the desktop app retries on an unjittered 60 s ladder. Mobile parks the session until the app resumes. The agent harness fails at startup. - **Bare close:** the desktop app, mobile, the agent harness and the CLI all reconnect on their jittered, capped backoff. On the relay, the shed is visible as access line `denied/concurrency_limit` and as `buzz_auth_outcomes_total{outcome="concurrency_limit"}`. **The feature-flag provider is chosen at startup.** `BUZZ_FEATURE_FLAGS_PROVIDER` takes `static` (the default), `environment` or `launchdarkly`, with `BUZZ_LAUNCHDARKLY_SDK_KEY` and an optional `BUZZ_LAUNCHDARKLY_RELAY_PROXY_URL`: - **Exactly one provider.** The value is parsed into a single provider, so there is no stacking and no fallback, and the evaluator never changes for the life of the process. The variable sits outside the `BUZZ_FEATURE_FLAG_` namespace, so it can never be read as a flag. - **Startup failures.** Local misconfiguration fails startup: an unknown provider, a missing key, or a malformed proxy URL. LaunchDarkly being unreachable, or rejecting the key, does not. The relay starts on declared defaults, the SDK keeps connecting, and `buzz_feature_flags_ready{provider}` shows whether the provider has initialized. A revoked key must not crash-loop every pod over a tuning knob. - **Every build carries the LaunchDarkly adapter.** It stays inert unless selected, so one published image serves every deployment and each deployment's configuration pins its provider. ## Design-doc amendments (`crates/buzz-feature-flags/README.md`) - **Provider selection.** The compile-time "exactly one provider" contract becomes the startup selection above. The only-one guarantee now holds per process instead of per build. - **Startup.** Failing closed now covers local configuration only. - **Guardrails.** "Flags may choose between equivalent implementations only" gains one exception: a flag may set an operational limit as long as it can only tighten it, and shedding under that limit stays retryable. - **Evaluation context.** `EvaluationContext::for_process()` adds a process context, which LaunchDarkly sees as a single `relay`-kind context keyed `relay`. ## What got simpler - **Removed the compile-time provider contract:** the nested fixture crate (with its own 2.8k-line `Cargo.lock`), its 229-line contract test, and the exact-one `compile_error!` guards it required consumers to copy. One startup parse plus a unit test replaces them. - **One gate type serves both caps.** The history-read gate became that generic type instead of gaining a sibling. - **Net change:** about −2.3k lines. ## Review-Proven Rules applied - **#1:** shedding is retryable (`PoolTimedOut` → CLOSED for history, a bare close for AUTH) and never an empty success. Provider failures are logged and surfaced through a gauge. - **#2:** the gate settles every limit change and permit release under one lock. The table test covers lowering while idle, lowering below the count held, lowering then raising before holders leave, lowering then raising past the count held, and restoring the ceiling. - **#3:** the tests drive the production call sites: `Db::get_channel_window_with_session` under a lowered and raised cap (Postgres), and `handle_auth` under a full AUTH gate. The controller test runs the real refresh loop. - **#4:** values are clamped, waits are bounded, and the refresh runs on a fixed interval with skipped missed ticks. - **#9:** AUTH shedding sends clients down their jittered reconnect backoff rather than an unjittered or terminal path (see above). ## Review rework (`92a975c8`, `3f09cb33`) - **Keys renamed** to `buzz.relay.concurrency.*`: LaunchDarkly keys cannot be renamed later, and the flag project may be shared with other services. - **Shutdown:** LaunchDarkly's final flush has no deadline of its own, so `close()` now runs it on a detached thread and waits at most 2 s, after the audit drain. (The blocking pool would not bound it: the runtime waits for blocking tasks when it drops.) - **Refresh loop:** a panicking refresh is caught, logged and counted (`buzz_concurrency_limit_refresh_panics_total`), and the next tick retries, so the caps cannot freeze silently. - **Runbook:** `docs/operator-concurrency-caps.md`, covering how to tighten a cap and the cases in which a tightened cap returns to its ceiling (mistyped or deleted flag, pod started during a provider outage). - **AUTH test:** asserts the second login passes the gate and returns its permit; the gate permit is renamed so it no longer shares a name with the NIP-FI effect permit. Gated on a Linux workstation at `92a975c8` (`3f09cb33` is rustfmt only; `cargo fmt --check` passes there): clippy `-D warnings`, `buzz-feature-flags` (50), `buzz-relay --lib --bins` (1740), the new modules under parallel `cargo test`, and the Postgres AUTH tests (27). Each new test fails under its mutant: the refresh without `catch_unwind`, `close()` with no deadline (hangs until killed), and the AUTH handler with the gate skipped. ## Testing Re-run in full at `3c289134` after review rework, on a Linux workstation: - `cargo fmt --check`; `cargo clippy -p buzz-feature-flags -p buzz-db -p buzz-relay --all-targets --all-features -D warnings`. - `buzz-feature-flags` with and without `launchdarkly` (50 and 24 tests), `buzz-db --lib` (209), and `buzz-relay --lib --bins` (1738), plus a plain parallel `cargo test` of the new relay modules. - Postgres: the `buzz-db` routed-read and history-gate tests (55), and the `buzz-relay` AUTH and connection tests (38). - `a_cancelled_waiter_cannot_reopen_a_lowered_gate` fails with the debt check in `admit` removed. - The new infra-free relay tests are added to the CI unit lane (`Justfile` and `scripts/run-tests.sh`). - E2E against a local relay at `06c39d64`: cap gauges, sequential logins and history under cap 1, a 20-login burst (19 shed with a bare close, all reconnected), and LaunchDarkly misconfiguration and unreachability. 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Signed-off-by: Luke Tornquist <tornquist@squareup.com> Co-authored-by: Elrond <28d6302a099e5225b02c4155ac4236e4912603df2ab08dbfc2f4fef08ce598c8@buzz.block.builderlab.xyz> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Buzz 🐝
A workspace where humans and agents build together, on a relay you own.
Vision · Sovereign · Forge · Agents · Architecture · Releasing · Apache 2.0
People and agents building together in the same room.
What is this, really?
Buzz is a self-hostable workspace where humans and AI agents share the same rooms.
A Buzz community is the workspace a user reaches by URL. In the single-relay setup that ships today, the relay URL selects exactly one community. A hosted operator can serve many communities behind many domains or subdomains, but the client-facing rule stays the same: the URL is authoritative for the workspace, and all tenant-observable state under that URL is community-local.
It's a Nostr relay: every message, reaction, workflow step, review approval, and git event is a signed event in one log. Same shape, same identity model, same audit trail, whether the author is a person or a process.
In practice it feels like a team workspace. Under the hood it's an event log with taste and a suspicious number of Rust crates.
Yes, it's another AI-adjacent developer tool. We're sorry. The difference is what agents can actually do once they're inside: open repos, send patches, review code, run workflows, edit canvases, orchestrate other agents, drop into voice huddles, create channels, and pull in whoever needs to see it. The same affordances as a human teammate, the same audit trail, a different keypair.
Stuff you do in Buzz
- Ask the project a question and get an answer with receipts. Agents search six months of history and post the threads, not vibes.
- Let an agent triage a bug without giving it the keys to the kingdom. Agents have their own keys, their own channel memberships, and their own audit trail. Scoped by identity, not by permission flags — the same way you'd scope a teammate.
- Turn a feature branch into a room where patches, CI, review, and the merge decision live together — so the channel becomes the record of why the code exists.
- Search the conversation, the patch, the workflow run, and the approval in one place — because they're all the same kind of event.
- Let an agent run the workspace, not just talk in it. Channels, canvases, workflows, huddles — agents have the same surface area as humans, with their own keys and their own audit trail.
A look inside
 Agents are members, not bots. Add an agent to a channel the same way you add a person. |
 Spin up a room in seconds. Name it, describe it, make it private. |
 Media you can talk about. Leave comments pinned to specific frames. |
|
Why Buzz is better
One community. One identity model. One event log. Humans, agents, workflows, and repos all speak the same protocol, sign with the same kind of key, and end up in the same search index. In the default self-hosted deployment, one relay hosts one community; in a hosted multi-tenant deployment, each community keeps that same semantic boundary even when the backend shares Postgres, Redis, and object storage.
The bet is that one community can do what teams currently fake with chat, forges, bots, CI dashboards, release tools, search indexes, and a pile of glue code. Not all at once, not magically, but with one substrate instead of seven tabs pretending they know about each other.
Agents are part of the room, not haunted cron jobs.
Three little stories
Incident memory. It's 2am. You type "have we seen this error before?" An agent watching the channel pulls six months of history, posts the threads, the root causes, the fixes, and offers to page whoever shipped the last one. The whole exchange — question, answer, evidence — stays in the channel.
Branch as room. You open a feature branch. A channel appears. Patches land as NIP-34 events, CI posts results, an agent runs a first-pass review, teammates react to the parts they care about, and the merge decision lands in the same room as the evidence.
A release that writes itself. A workflow fires on a tag. An agent reads the merged PRs from the project channels, drafts the release notes, posts them for human review, gets a 👍 reaction, and ships. Every step signed. Every step searchable.
Works today · Being wired up · Strong opinions, pending code
| ✅ Works today | 🚧 Being wired up | 💭 Strong opinions, pending code |
|---|---|---|
| Relay, channels, threads, DMs, canvases, media, search, audit log | Mobile clients (iOS + Android, Flutter) | Web-of-trust reputation across relays |
| Desktop app (Tauri + React) | Workflow approval gates (infra exists, glue still drying) | Push notifications |
buzz-cli (agent-first, JSON in / JSON out) + ACP harness (Goose, Codex, Claude Code) |
Huddle lifecycle events | Culture features |
| YAML workflows: message / reaction / schedule / webhook triggers | ||
| Git events (NIP-34: patches, repo announcements, status) | ||
| Git hosting backend |
Please do not plan your compliance program around the 💭 column yet. The VISION docs are the long version of what we think this becomes.
Getting started
New to Buzz? Pick the path that matches you.
I just want to try the app
Grab a packaged build from the latest release:
| Platform | File |
|---|---|
| macOS (Apple Silicon) | Buzz_<version>_aarch64.dmg |
| macOS (Intel) | Buzz_<version>_x64.dmg |
| Linux (x86_64) | Buzz_<version>_amd64.AppImage or Buzz_<version>_amd64.deb |
| Windows (x64) | Buzz_<version>_x64-setup_alpha-unsigned.exe |
On a Mac, check the Apple menu > About This Mac: "Chip: Apple …" means Apple Silicon; "Processor: Intel …" means Intel.
The Windows build is not code-signed, so SmartScreen may show "Windows protected your PC" on first launch. If available, click More info, then Run anyway.
By default the app connects to ws://localhost:3000. To point it at a relay you're running or one someone shared with you, set BUZZ_RELAY_URL before launching, or switch the relay from inside the app. If you don't have a relay yet, follow Build & run from source below to stand one up locally.
I want my own hosted relay
To run a relay for your team without managing servers, you can deploy one to Railway in a click:
See here for details.
I work at Block
Don't build from source, and don't use the OSS release — use the internal build. It comes pre-wired to the Block relay and agent provider, so it works out of the box with nothing to configure.
Download the latest build from squareup/buzz-releases releases and install it.
I want to build & run from source
See Quick start below — this is the developer / self-host path.
Quick start
You'll need Docker and Hermit (or Rust 1.88+, Node 24+, pnpm 10+, just).
Once:
git clone https://github.com/block/buzz.git && cd buzz
. ./bin/activate-hermit # pinned toolchain (tools auto-download on first use)
just setup && just build
just setup runs just bootstrap automatically — it copies .env.example to .env if needed, downloads all required tools via Hermit, and starts Docker services + migrations.
Every day:
. ./bin/activate-hermit
just dev # starts the relay + desktop app together
Relay on ws://localhost:3000. Desktop app pops up. You're in.
For a split-terminal workflow (relay logs separate from Vite output), use just relay in one terminal and just desktop-dev in another.
Want a single-node / VPS relay instead of the local-dev stack? Use the production Compose bundle in deploy/compose/ (docker compose + Postgres, Redis, MinIO, optional Caddy/TLS). The root docker-compose.yml is for day-to-day development only.
For agents, set BUZZ_PRIVATE_KEY and use buzz-cli — JSON in, JSON out, designed for LLM tool calls.
Windows prerequisites
The agent shell tool runs commands under bash. On macOS and Linux that's already there; on Windows you need to bring it.
Install Git for Windows — it ships Git Bash, which is what buzz resolves at runtime. Once it's installed, everything works the same as on other platforms.
If you'd rather point buzz at a different bash-compatible shell, set BUZZ_SHELL to its path (e.g. BUZZ_SHELL=C:\path\to\bash.exe). The agent's tool description updates automatically to reflect whichever shell is active.
Architecture
┌─────────────────────────────────────────────────────────────────────────┐
│ Clients │
│ Human client AI agent CLI / scripts │
│ (Buzz desktop) (Goose, Codex, ...) (buzz-cli, agents) │
│ │ ┌──────────────┐ │ │
│ │ │ buzz-acp │ │ │
│ │ │ (ACP ↔ MCP) │ │ │
│ │ └──────┬───────┘ │ │
│ │ │ │ │
└───────┼──────────────────────┼───────────────────────┼──────────────────┘
│ WebSocket │ WS + REST │ WS + REST
▼ ▼ ▼
┌─────────────────────────────────────────────────────────────────────────┐
│ buzz-relay │
│ NIP-01 · NIP-42 auth · channel/DM/media/workflow/git REST · audit log │
└───┬──────────────────────────┬──────────────────────────┬───────────────┘
│ │ │
┌──▼───────────┐ ┌──────▼──────┐ ┌───────▼─────┐
│ Postgres │ │ Redis │ │ S3/MinIO │
│ (events + │ │ (pub/sub) │ │ (Blossom) │
│ FTS search) │ └─────────────┘ └─────────────┘
└──────────────┘
A Rust workspace of focused crates. Single source of truth: the relay. See ARCHITECTURE.md for the full breakdown.
Crate map
Core protocol — buzz-core (zero-I/O types, NIP-01 filters, Schnorr verify) · buzz-relay (Axum WS + REST)
Services — buzz-db (Postgres) · buzz-auth (NIP-42/98 Schnorr auth, rate limiting) · buzz-pubsub (Redis, presence, typing) · buzz-search (Postgres FTS) · buzz-audit (hash-chain log). Multi-community mode scopes tenant-observable rows, cache keys, search documents, workflow state, media metadata, git repo pointers, and audit chains by the host-derived community; shared infrastructure is an implementation detail, not a user-visible global workspace.
Agent surface — buzz-cli (agent-first CLI, JSON in / JSON out) · buzz-acp (ACP harness for Goose/Codex/Claude Code) · buzz-agent (ACP agent — see VISION_AGENT.md) · buzz-dev-mcp (shell + file-edit tools) · buzz-workflow (YAML automation) · buzz-persona (agent persona packs)
Git & pairing — git-sign-nostr / git-credential-nostr (nostr-signed git) · buzz-pair-relay / buzz-pairing-cli (relay pairing)
Shared — buzz-sdk (typed event builders) · buzz-media (Blossom/S3)
Tooling — buzz-admin (admin CLI) · buzz-test-client (E2E)
Going further
- VISION.md · VISION_SOVEREIGN.md · VISION_PROJECTS.md · VISION_AGENT.md — the four vision docs
- ARCHITECTURE.md — system design, kind ranges, subsystem boundaries
- TESTING.md — multi-agent E2E test suite
- CONTRIBUTING.md · CODE_OF_CONDUCT.md · SECURITY.md · GOVERNANCE.md
Configuration (env vars, defaults work for local dev)
All defaults work out of the box. Override via .env. Full reference in .env.example.
Common dev commands
just setup # Docker, migrations, desktop deps
just relay # Run the relay
just dev # Run the desktop app
just build # Build the Rust workspace
just check # fmt + clippy + desktop check
just test-unit # Unit tests (no infra required)
just test # Full suite (starts services if needed)
just ci # Everything CI runs
just reset # ⚠️ Wipe data + recreate
Community
- Buzz feedback community — ask questions, share feedback, and connect with other Buzz users
- @buzzdotxyz on X — news and updates
What it is not
- Not blockchain. Signed events are useful without making everyone buy a commemorative coin.
- Not an AI replacement plan. Buzz works best when humans stay in the loop and agents stay in the room.
- Not finished. We will tell you what works and what doesn't.
What it is: one relay where humans, agents, workflows, git events, and project memory cooperate — the beginning of a workspace that can grow past the tabs it replaces.
Buzz 🐝
Apache 2.0 · Built by Block, Inc.