2f2f6e2774
## Problem An agent `#p` + `#h` + `since` REQ (the `require_mention` subscription in `buzz-acp`) ran for over 45 minutes on a production writer and held `AccessShare` on every `events` partition. There were two causes: 1. **The mention side of the `#p` join was unbounded.** `build_query_events_sql` joined `event_mentions` on `(community_id, event_id)` only. The planner picked a nested loop whose outer side was every mention of the pubkey, ever, and whose inner side range-scanned the channel index from `since` on each partition. Cost ≈ total mentions × channel rows since `since`. 2. **Nothing cancelled it.** The writer `statement_timeout` defaulted to `0`. Only `#e` reads had a deadline (the 20s cap from #7854), and read-replica sessions had none at all. `pg_stat_statements` shows this shape has a multi-thousand-second max going back months, so it is chronic and was not introduced by a recent change. ## Change **`#p` mention bound** (`store/event.rs`, `push_mention_join`, shared by the page SELECT and COUNT) - Join on the full event key, `AND e.created_at = m.event_created_at`. Mention rows copy the event's `created_at` at insert (migration 0007 already relies on this equality), so the join can prune `events` partitions by time. - Repeat `since`/`until` on `m.event_created_at`, so the outer scan is a range on the existing `idx_event_mentions_pubkey_created`. `until` is a superset bound for the keyset cursor; the exact `(created_at, id)` cursor test stays on `e`. - Repeat `kinds` on `m.event_kind` when the filter has kinds. Every production mention writer binds the event kind (`insert_mentions` in `store/runtime/mod.rs`, and the replaceable-event path in `store/replaceable.rs`, back to the first Postgres schema), and no migration inserts mention rows, so this drops no rows written by the relay. Rows imported out of band with a NULL `event_kind` would no longer match a kinds-filtered `#p` read; a read-only production count on 2026-10-20 found 0 such rows on both production reader databases. The pushdown makes `idx_event_mentions_pubkey_kind_created` available to the planner for the `require_mention` kind-9 shape; its use has not been observed (see below). An E2E fixture with a hand-set NULL `event_kind` row confirmed the caveat: base returns 8 events, head 7. - The feed's mentions and needs-action queries (`store/feed.rs`, `build_mentions_query` / `build_needs_action_query`) join `event_mentions` the same way, so each joined row probes one `events` partition instead of all of them. Their `ORDER BY m.event_created_at ... LIMIT` already kept them from running away; this removes the per-row cross-partition probe. - Observed plan (E2E at `9cb6638b1`, before the `kinds` pushdown; 60,000 historical mentions + 2,500 recent decoys, stock planner, `EXPLAIN (ANALYZE, BUFFERS)` of the captured production SQL): the mention side is a bounded range on `idx_event_mentions_pubkey_created` (13 rows), then a hash join with a scan of the recent `events` partition. Base scanned 2,509 recent events and probed `event_mentions_pkey` 2,509 times. Head: **1.1 ms / 319 shared hits**; base: **8.5 ms / 10,049 shared hits**. Not measured against the production replica. A fresh `EXPLAIN (ANALYZE, BUFFERS)` replay at `a7065c367`, after the pushdown, ran on a smaller fixture where the planner chose a sequential mention scan, so it neither confirms nor replaces these numbers. **Reads: 20s deadline on every generic event read** - `query_events_on` and `count_events_on` always run under the transaction-local 20s deadline that `#e` reads used (`fetch_with_read_deadline`, formerly `fetch_with_e_tag_deadline`). It only tightens: shorter operator or caller caps are kept. - Read-replica sessions get a 20s session default through `after_connect`, using the same tighten-only SQL. - Cost: every generic REQ history read and COUNT now pays BEGIN + `set_config` + ROLLBACK (three extra round trips; before, only `#e` reads did). In the local E2E the end-to-end history read was still faster at head (median 4.1 ms vs 10.2 ms at base, 9 samples each, warm cache), so the round trips are dominated by the bounded plan; this does not isolate them or establish production p99. The round trips also lengthen how long each such read holds its writer connection; that hold time has not been measured against production pool sizing. - A replica read cancelled at its deadline (57014) is returned, not re-run on the writer. Usually the cancel means expensive work the writer would only repeat. It can also mean the replica waited on a lock only it holds (a replayed `ACCESS EXCLUSIVE` from primary DDL), when the writer would have answered quickly; that miss is the accepted price of keeping runaway reads off the primary. The rationale now lives once on `DbError::is_statement_cancelled` instead of in a dozen copied comments. The generic routed reads and `ReadSession` already did this; the eight routed reads with their own SQL (feed mentions, needs-action and activity; thread replies; channel window; relay membership; thread window and its auxiliary scan) now do too. A cancelled auxiliary scan also keeps its replica session instead of degrading it to the writer for the rest of the request. Other replica failures (e.g. hot-standby recovery conflicts) still fall back to the writer. - Paths with their own tighter `SET LOCAL` (artifact 2–5s, thread window 4s, personal reads, usage 5–15s, serving lease 1.5s) are unchanged. **Writes: every writer session is bounded** - The default `statement_timeout` changes from `0` to 120s (`DEFAULT_STATEMENT_TIMEOUT_MS`). - `BUZZ_DB_STATEMENT_TIMEOUT_MS` still overrides it. `0` or any value above 300s installs 300s (`MAX_STATEMENT_TIMEOUT_MS`), so a session can no longer disable it, and a clamped value logs a `warn!` when the pool is built. Only the operator-approved, fenced destruction paths below lift it, per transaction. **Long-running writer paths, audited** | Path | Behavior | |---|---| | Migrations / schema destruction (`with_exclusive_schema_destruction_lock`) | Unchanged: these lift lock and statement timeouts on their own detached connection | | Partition maintenance | Unchanged: own 5s `statement_timeout` | | Partition audit (`buzz-admin`) | Unchanged: 30s | | Community deletion inventory, purge and logical verification (`inventory_schema` whole-tenant counts, `purge_postgres` whole-community `DELETE` per table in one tx, `verify_postgres_logically_deleted` whole-tenant `EXISTS` per table right after the purge) | Lifted (`statement_timeout = 0`) transaction-locally by `lift_statement_timeout`, like migrations; lock and idle timeouts still bound them. Inventory counts each table in its own lifted transaction, so each table's lock and snapshot are released as soon as its count finishes, as the autocommit counts did. A cancelled purge would retry from scratch and eventually block, so a cap here would turn large-tenant deletion into an operator override | | Audit appends (`buzz-audit`, audit pool inherits the writer cap) | Waits on the audit-chain advisory lock. With `BUZZ_DB_LOCK_TIMEOUT_MS=0` (or at least the statement cap), `statement_timeout` (57014) cancels the wait instead of `lock_timeout` (55P03). The relay's audit worker now retries both with the same backoff instead of dropping the entry on 57014; admission refusal stays terminal | On HTTP routes a statement timeout already maps to the distinct retryable 503 (`api/mod.rs`, `statement_timeout_maps_to_distinct_503`). A cancelled REQ fails its history read instead of hanging. ## Tests - `p_tag_query_bounds_mention_side_by_time` (unit): page and COUNT SQL carry the `created_at` join and the `since`/`until`/`kinds` mention bounds, and the bounds are absent when the filter has none. - `p_tag_read_with_mention_bounds_keeps_results` (Postgres): through the production mention insert, unbounded, `since`, window and keyset-cursor reads return exactly the mentioned rows, and COUNT matches. Every bound sits exactly on a mentioned row's second and the cursor page includes a same-second sibling after the cursor id, so an off-by-one on either mention-side bound fails it. - `plain_read_is_cancelled_at_deadline_when_timeout_disabled` / `count_events_cancels_at_read_deadline_when_timeout_disabled` (Postgres): the production `#p` + `#h` + `since` shape and a plain COUNT are cancelled at 20s with the session timeout disabled. Previously these covered `#e` only. - `writer_statement_timeout_is_always_bounded` (unit) and `session_statement_timeouts_bound_writer_and_reader_sessions` (Postgres): through `Db::new`, writer sessions install `2min` / `5min` (for `0` and for 600s) / `45s`, and replica sessions install `20s`. - `deletion_whole_tenant_stages_outlive_the_writer_statement_timeout` (Postgres): on a scratch desired-state database with a 500ms writer cap, the real `inventory_schema`, `purge_postgres` and `verify_postgres_logically_deleted` each wait behind a held `ACCESS EXCLUSIVE` lock on `events` for over 1s and still complete, a plain statement is cancelled (57014), and pooled sessions still read `500ms` afterwards. A lifted transaction reads `statement_timeout = 0`, so a bounded lift (e.g. `'300000'`) fails it, as does removing any of the three `lift_statement_timeout` calls. - `mentions_query_is_tenant_scoped_and_joins_mentions_by_composite_key` / `needs_action_query_is_tenant_scoped_and_joins_mentions_by_composite_key` (unit): both feed queries carry the `e.created_at = m.event_created_at` join. - `replica_statement_cancel_propagates_without_writer_rerun` (Postgres): with the replica locked past its cap, each of the six routed reads above returns 57014 instead of the writer's copy. Removing the cancel arm in any of them fails it. - `thread_window_statement_cancel_propagates_without_writer_rerun` (Postgres): a thread-window read parked behind a replica lock and cancelled (57014; the window's own 1s `lock_timeout` would otherwise fire first) returns the cancel instead of the unlocked writer's window, and an auxiliary scan timed out on a replica session returns 57014 and leaves the session on the replica. Removing either guard fails it. - `audit_worker_retries_statement_timeout_until_original_entry_is_appended_once` (Postgres, `buzz-relay`): the production audit worker, with `lock_timeout` disabled and a 100ms statement cap, keeps the entry through repeated 57014 cancels while the chain lock is held and appends it exactly once after release. Treating only 55P03 as retryable fails it. - The existing writer and audit-pool GUC tests now expect `5min` for a disabled statement timeout. ## After deploy, watch - `buzz_db_route_decision{decision="replica",reason="statement_cancelled"}`: replica reads that now fail instead of falling back to the writer, including the replica-only lock case above. - `buzz_db_pool_acquire_wait_seconds` and `buzz_db_pool_waiters` on the writer pool: every generic REQ history read and COUNT now holds its connection for three extra round trips. ## Database checklist (`docs/database.md` § Review checklist) This PR changes schema-dependent `buzz-db` queries (the `#p` join and its `m.event_kind` pushdown). It does not change the schema. - **Phase:** none. No schema change, so this is not an expand, backfill or contract step. Nothing before or after it is required. - **Triggers, functions, procedures, rules, foreign keys:** none added. - **Row mutations / backfill:** no migration, and no row is mutated or backfilled. The one data-shape dependency is mention rows with a NULL `event_kind`: a kinds-filtered `#p` read no longer matches them (see the `kinds` bullet under Change). Relay writers always bind `event_kind`, so only rows imported out of band are affected. A read-only production count on 2026-10-20 found 0 such rows on both production reader databases. - **Contract migration:** N/A. - **Rule 4 locations:** none touched. No table, index or desired-state file changes, so no parity test applies. The new bounds use the existing `idx_event_mentions_pubkey_created` and `idx_event_mentions_pubkey_kind_created`. - **Deployed relay vs. new schema:** there is no new schema. The currently deployed relay and this relay run against the same tables. - **Lock and statement timeouts:** this PR is about them. Generic reads get a 20s deadline, replica sessions a 20s default, and writer sessions a 120s default capped at 300s. Community-deletion transactions lift `statement_timeout` per transaction; migrations and schema destruction are unchanged (see "Long-running writer paths, audited"). No index builds and no operator prebuild step. ## What got simpler - One read-deadline path instead of an `#e`-only branch in `query_events_on` and `count_events_on`. - The `#p` join SQL that was duplicated between SELECT and COUNT now lives in one `push_mention_join`. - The deletion tests share one scratch desired-state database helper instead of an inline copy. - "Is this query bounded?" now has one answer: yes, unless it runs in a migration, schema destruction, or community-deletion transaction. ## Identified debt (not in this PR) - `buzz-acp` re-sends the same filter after a timeout `CLOSED` (no backoff or narrowing). With the `#p` bound the `require_mention` read should finish well inside 20s, so this is a follow-up, not a blocker. --------- Signed-off-by: Elrond <28d6302a099e5225b02c4155ac4236e4912603df2ab08dbfc2f4fef08ce598c8@buzz.block.builderlab.xyz> Co-authored-by: Elrond <28d6302a099e5225b02c4155ac4236e4912603df2ab08dbfc2f4fef08ce598c8@buzz.block.builderlab.xyz>
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.