Bump to v2026.9.23

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.claude/launch.json

@@ -1,17 +0,0 @@
-{
-  "version": "0.0.1",
-  "configurations": [
-    {
-      "name": "frontend",
-      "runtimeExecutable": "npm",
-      "runtimeArgs": ["--prefix", "frontend", "run", "dev"],
-      "port": 5173
-    },
-    {
-      "name": "frontend-preview",
-      "runtimeExecutable": "npm",
-      "runtimeArgs": ["--prefix", "frontend", "run", "preview"],
-      "port": 4173
-    }
-  ]
-}

.gitignore

@@ -17,6 +17,7 @@ dist-ssr/
 ## Editors / OS
 .vscode/
 .idea/
+.claude/
 .DS_Store
 
 ## Test / coverage

CONTRIBUTING.md

@@ -0,0 +1,51 @@
+# Contributing to DS Chat
+
+Thanks for considering a contribution.
+
+## Reporting bugs and requesting features
+
+Open an issue on this project's issue tracker. Include steps to reproduce
+for a bug, or the problem you're trying to solve for a feature request —
+that's usually more useful than a proposed solution.
+
+## Development setup
+
+See the root [README.md](README.md)'s Quickstart, plus
+[backend/README.md](backend/README.md) and
+[frontend/README.md](frontend/README.md) for the full local dev setup
+(Postgres, Redis, Python venv, migrations, the Vite dev server).
+[ARCHITECTURE.md](ARCHITECTURE.md) covers the overall system design if
+you're orienting yourself before a larger change.
+
+## Before opening a pull request
+
+- **Tests**: run `pytest` in `backend/` for any backend change, and add
+  tests for new behavior rather than just the happy path — see
+  `backend/README.md`'s "Run tests" section. For frontend changes, run
+  `npx tsc -b` in `frontend/` and confirm `npm run build` succeeds.
+- **Style**: match the conventions already in the file you're editing
+  rather than introducing a new pattern — this codebase doesn't have a
+  separate style guide beyond "look at what's already there."
+- **Scope**: smaller, focused PRs are easier to review than large ones
+  that mix unrelated changes.
+
+## Contributor terms
+
+By submitting a contribution (a pull request, patch, or similar), you
+agree that:
+
+1. Your contribution is licensed under the project's own license,
+   AGPL-3.0-or-later ([LICENSE](LICENSE)), and
+2. You grant the project's maintainer(s) a perpetual, worldwide,
+   non-exclusive right to also relicense your contribution under different
+   terms — for example, as part of a separately-licensed commercial
+   offering built on this project.
+
+This keeps the option of a future dual-licensed (open-source +
+commercial) version of the project available, without requiring a
+separate signed agreement for every contribution.
+
+*This is a lightweight starting point, not a substitute for legal advice —
+if you're contributing something substantial, or maintaining a fork with
+your own commercial plans, it's worth having this reviewed by a lawyer
+rather than relying on the paragraph above alone.*

DEPLOYMENT.md

@@ -132,35 +132,45 @@ sudo -u ds-chat ssh-keygen -t ed25519 -f /srv/ds-chat/.ssh/id_ed25519 -N ""
 sudo cat /srv/ds-chat/.ssh/id_ed25519.pub
 ```
 
-Add that public key as a **read-only deploy key** on the Gitea repo
+This project is hosted at
-(Settings → Deploy Keys), then:
+**[github.com/ds-ksmith/DS-Chat](https://github.com/ds-ksmith/DS-Chat)**.
+Add that public key there as a **read-only deploy key** (Settings → Deploy
+Keys on the repo), then:
 
 ```bash
-sudo -u ds-chat ssh-keyscan git.darksingularity.org >> /srv/ds-chat/.ssh/known_hosts
+sudo -u ds-chat ssh-keyscan github.com >> /srv/ds-chat/.ssh/known_hosts
-sudo -u ds-chat git clone git@git.darksingularity.org:DarkSingularity/ds-chat.git /srv/ds-chat
+sudo -u ds-chat git clone git@github.com:ds-ksmith/DS-Chat.git /srv/ds-chat
 ```
 
-(If your Gitea's SSH is on a non-default port, adjust the clone URL and
+(Deploying from your own fork instead? Substitute its clone URL — the same
-`ssh-keyscan -p <port>` accordingly.)
+deploy-key/access-token steps work the same way on GitHub, GitLab, Gitea,
+and most other git hosts.)
 
 **Alternative: a personal/deployment-user access token instead of a deploy
 key** — skip the `.ssh`/`ssh-keygen`/`ssh-keyscan` commands above entirely
 and clone over HTTPS with the token embedded in the URL:
 
 ```bash
-sudo -u ds-chat git clone https://<TOKEN>@git.darksingularity.org/DarkSingularity/ds-chat.git /srv/ds-chat
+sudo -u ds-chat git clone https://<TOKEN>@github.com/ds-ksmith/DS-Chat.git /srv/ds-chat
 ```
 
 The token then lives in plaintext in `/srv/ds-chat/.git/config` (`git
 remote -v` shows it) — readable by root and the `ds-chat` user, not by
 anyone else under normal file permissions. `deploy/upgrade.sh`'s later
-`git pull`s reuse this same authenticated URL automatically, no extra
+`git fetch`es reuse this same authenticated URL automatically, no extra
 setup needed. Fine as long as the token is scoped to read-only access on
 just this repo.
 
-Either way, now that the repo is cloned:
+Either way, now that the repo is cloned, check out the latest release tag
+rather than deploying whatever the default branch's tip happens to be —
+`deploy/upgrade.sh` follows the same rule on every later upgrade (see §6),
+so this keeps the very first deploy consistent with all the ones after it:
 
 ```bash
+cd /srv/ds-chat
+sudo -u ds-chat git fetch --tags
+LATEST_TAG="$(sudo -u ds-chat git tag --sort=-creatordate | head -n1)"
+sudo -u ds-chat git checkout --detach "$LATEST_TAG"
 sudo -u ds-chat mkdir -p /srv/ds-chat/uploads
 ```
 
@@ -232,7 +242,16 @@ admin sets it up.
 `/ws`) whenever that directory exists — that's what lets Nginx Proxy
 Manager forward the whole domain to one port with no custom path routing.
 
+Before building, copy `frontend/.env.example` to `frontend/.env.production`
+and set `VITE_SOURCE_URL` to wherever *your* copy of the repo lives — see
+that file's own comment for why this matters (AGPL-3.0 source-availability
+compliance). Vite bakes this in at build time, so it needs to be in place
+before `npm run build` runs, and needs re-running after any future change
+to it.
+
 ```bash
+sudo -u ds-chat cp /srv/ds-chat/frontend/.env.example /srv/ds-chat/frontend/.env.production
+sudo -u ds-chat nano /srv/ds-chat/frontend/.env.production  # set VITE_SOURCE_URL
 sudo -u ds-chat bash -c 'cd /srv/ds-chat/frontend && npm ci && npm run build'
 ```
 
@@ -320,12 +339,15 @@ This is config in NPM's own UI/database, not a file this repo ships:
 sudo -u ds-chat /srv/ds-chat/deploy/upgrade.sh
 ```
 
-Pulls latest `main`, reinstalls backend deps, runs `alembic upgrade head`,
+Fetches tags and checks out whichever one sorts newest (`git tag
-rebuilds the frontend, restarts `ds-chat`, and curls `/api/health` to
+--sort=-creatordate`) — deliberately not the default branch's tip, so
-confirm it came back up. Fails loudly (`set -euo pipefail`) and stops
+running this between releases is a safe no-op rather than pulling in
-before restarting anything if an earlier step — most importantly a failed
+whatever's mid-flight on `main`. Then reinstalls backend deps, runs
-migration — errors out, so a bad deploy doesn't take down the previously
+`alembic upgrade head`, rebuilds the frontend, restarts `ds-chat`, and
-working one.
+curls `/api/health` to confirm it came back up. Fails loudly
+(`set -euo pipefail`) and stops before restarting anything if an earlier
+step — most importantly a failed migration — errors out, so a bad deploy
+doesn't take down the previously working one.
 
 Active users get disconnected for a few seconds during the restart and
 reconnect automatically (same reconnect logic as §4's NPM-timeout note) —

LICENSE

@@ -629,8 +629,8 @@ to attach them to the start of each source file to most effectively
 state the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
 
-    <one line to give the program's name and a brief idea of what it does.>
+    DS Chat, a self-hosted, real-time team chat service.
-    Copyright (C) <year>  <name of author>
+    Copyright (C) 2026  Keith Smith
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU Affero General Public License as published by

backend/app/ws/broadcaster.py

@@ -1,10 +1,13 @@
 import json
+import logging
 import uuid
 
 from redis.asyncio import Redis
 
 from app.ws.connection_manager import ConnectionManager
 
+logger = logging.getLogger(__name__)
+
 ROOM_CHANNEL_PREFIX = "room:"
 USER_CHANNEL_PREFIX = "user:"
 
@@ -43,14 +46,26 @@ class Broadcaster:
             async for message in pubsub.listen():
                 if message["type"] != "pmessage":
                     continue
-                channel = message["channel"]
+                # #76: this is the one pubsub listener for the whole process
-                payload = json.loads(message["data"])
+                # (see main.py's lifespan) -- ConnectionManager.broadcast/
-                if channel.startswith(ROOM_CHANNEL_PREFIX):
+                # send_to_user already guard against one dead socket taking
-                    room_id = uuid.UUID(channel.removeprefix(ROOM_CHANNEL_PREFIX))
+                # the rest of a single fan-out down, but this belt-and-
-                    await self._manager.broadcast(room_id, payload)
+                # suspenders catch is for anything else unexpected (a
-                elif channel.startswith(USER_CHANNEL_PREFIX):
+                # malformed payload, e.g.) doing the same. An uncaught
-                    user_id = uuid.UUID(channel.removeprefix(USER_CHANNEL_PREFIX))
+                # exception here previously meant *this whole async for*
-                    await self._manager.send_to_user(user_id, payload)
+                # loop died silently -- no more live delivery to any room on
+                # this instance, for anyone, until the process restarted.
+                try:
+                    channel = message["channel"]
+                    payload = json.loads(message["data"])
+                    if channel.startswith(ROOM_CHANNEL_PREFIX):
+                        room_id = uuid.UUID(channel.removeprefix(ROOM_CHANNEL_PREFIX))
+                        await self._manager.broadcast(room_id, payload)
+                    elif channel.startswith(USER_CHANNEL_PREFIX):
+                        user_id = uuid.UUID(channel.removeprefix(USER_CHANNEL_PREFIX))
+                        await self._manager.send_to_user(user_id, payload)
+                except Exception:
+                    logger.error("Error handling pubsub message on channel %s", message.get("channel"), exc_info=True)
         finally:
             await pubsub.punsubscribe(f"{ROOM_CHANNEL_PREFIX}*", f"{USER_CHANNEL_PREFIX}*")
             await pubsub.aclose()

backend/app/ws/chat.py

@@ -1,3 +1,4 @@
+import asyncio
 import uuid
 
 from fastapi import APIRouter, Depends, WebSocket, WebSocketDisconnect
@@ -31,6 +32,18 @@ router = APIRouter(tags=["ws"])
 
 WS_UNAUTHENTICATED = 4401
 
+# #76: comfortably under the ~60s idle-connection timeout common to reverse
+# proxies/load balancers sitting in front of this endpoint, and short enough
+# that the frontend's own zombie-detection watchdog (useChatSocket.ts) can
+# notice a dead connection and reconnect well within a session -- a socket
+# can go silently dead (no close frame at all, e.g. a laptop sleeping or a
+# NAT dropping an idle mapping) without this, and no live message reaches it
+# again until *something* else finally triggers a close, which used to be
+# "switch rooms and back" purely by accident (that remounts the message
+# list, which refetches history over plain REST -- unrelated to the socket
+# itself actually recovering).
+WS_PING_INTERVAL_SECONDS = 30
+
 
 class ClientEnvelope(BaseModel):
     type: str
@@ -124,7 +137,18 @@ async def chat_endpoint(websocket: WebSocket, db: AsyncSession = Depends(get_db)
 
     try:
         while True:
-            raw = await websocket.receive_json()
+            try:
+                raw = await asyncio.wait_for(
+                    websocket.receive_json(), timeout=WS_PING_INTERVAL_SECONDS
+                )
+            except asyncio.TimeoutError:
+                # Nothing received in a while -- ping rather than assume the
+                # connection's still good. A genuinely dead socket fails this
+                # send (raising, caught below same as any other disconnect);
+                # a merely quiet one just gets proded and the loop continues
+                # waiting.
+                await websocket.send_json({"type": "ping"})
+                continue
             try:
                 try:
                     envelope = ClientEnvelope.model_validate(raw)
@@ -146,6 +170,14 @@ async def chat_endpoint(websocket: WebSocket, db: AsyncSession = Depends(get_db)
                     joined_rooms.add(envelope.room_id)
                     await websocket.send_json({"type": "joined", "room_id": str(envelope.room_id)})
 
+                elif envelope.type == "pong":
+                    # #76: the client's reply to our "ping" above -- nothing
+                    # to do with it. Its only purpose is resetting the
+                    # frontend's own liveness watchdog; the timeout on the
+                    # receive_json() above already gets reset by receiving
+                    # any frame at all, this one included.
+                    pass
+
                 elif envelope.type == "leave":
                     if envelope.room_id is None:
                         await websocket.send_json({"type": "error", "detail": "room_id required"})

backend/app/ws/connection_manager.py

@@ -1,8 +1,11 @@
+import logging
 import uuid
 from collections import defaultdict
 
 from fastapi import WebSocket
 
+logger = logging.getLogger(__name__)
+
 
 class ConnectionManager:
     """Local, single-process WebSocket socket registry.
@@ -43,8 +46,22 @@ class ConnectionManager:
 
     async def broadcast(self, room_id: uuid.UUID, payload: dict) -> None:
         for websocket in list(self._rooms.get(room_id, ())):
-            await websocket.send_json(payload)
+            # #76: one dead/racing socket (e.g. its own disconnect cleanup
+            # hasn't finished removing it from _rooms yet) must not take the
+            # rest of this broadcast down with it -- this runs inside
+            # Broadcaster.listen()'s single, never-restarted per-process
+            # pubsub loop, so an unhandled exception here previously meant
+            # one bad socket silently killed *live delivery for every room
+            # on this instance*, not just the one socket, until the process
+            # was restarted.
+            try:
+                await websocket.send_json(payload)
+            except Exception:
+                logger.warning("Dropping dead socket during broadcast to room %s", room_id, exc_info=True)
 
     async def send_to_user(self, user_id: uuid.UUID, payload: dict) -> None:
         for websocket in list(self._users.get(user_id, ())):
-            await websocket.send_json(payload)
+            try:
+                await websocket.send_json(payload)
+            except Exception:
+                logger.warning("Dropping dead socket sending to user %s", user_id, exc_info=True)

backend/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "ds-chat"
-version = "2026.9.3"
+version = "2026.9.23"
 description = "DS Chat backend service"
 license = { text = "AGPL-3.0-or-later" }
 requires-python = ">=3.11"

backend/tests/test_ws_chat.py

@@ -109,6 +109,24 @@ def test_history_tiebreaks_identical_timestamps_by_id(ws_client):
     assert [m["content"] for m in history] == [m["content"] for m in expected_order]
 
 
+def test_ws_sends_heartbeat_ping(ws_client, monkeypatch):
+    # #76: with nothing else sent on the connection, a "ping" must arrive
+    # proactively once the idle timeout elapses -- shrunk here so the test
+    # doesn't actually wait the real 30s. Replying "pong" (the frontend's
+    # own behavior) must be accepted silently and leave the connection
+    # fully usable afterward, not treated as an unknown message type.
+    monkeypatch.setattr("app.ws.chat.WS_PING_INTERVAL_SECONDS", 0.05)
+    username = _unique("alice")
+    _register(ws_client, username=username)
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    with ws_client.websocket_connect("/ws/chat") as ws:
+        assert ws.receive_json() == {"type": "ping"}
+        ws.send_json({"type": "pong"})
+        ws.send_json({"type": "join", "room_id": room["id"]})
+        assert ws.receive_json() == {"type": "joined", "room_id": room["id"]}
+
+
 def test_ws_message_without_join_errors(ws_client):
     _register(ws_client, username=_unique("alice"))
     room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()

deploy/upgrade.sh

@@ -16,9 +16,18 @@ BACKEND_DIR="${REPO_DIR}/backend"
 FRONTEND_DIR="${REPO_DIR}/frontend"
 ENV_FILE="/etc/ds-chat/env"
 
-echo "==> Pulling latest code"
+echo "==> Fetching latest release"
 cd "$REPO_DIR"
-git pull --ff-only
+git fetch --tags --force
+LATEST_TAG="$(git tag --sort=-creatordate | head -n1)"
+if [[ -z "$LATEST_TAG" ]]; then
+  echo "No tags found -- nothing to deploy" >&2
+  exit 1
+fi
+echo "Deploying $LATEST_TAG"
+# Detached HEAD, not a branch checkout -- this directory only ever runs a
+# tagged release, never whatever the default branch's tip happens to be.
+git checkout --quiet --detach "$LATEST_TAG"
 
 echo "==> Installing backend dependencies"
 cd "$BACKEND_DIR"

frontend/.env.example

@@ -0,0 +1,7 @@
+# Shown as the "Source code" link in the app's About screen -- required
+# for AGPL-3.0 section 13 compliance once you deploy this (a link so users
+# interacting with the app over the network can get the actual source,
+# including any modifications you've made). The default below points at
+# the upstream project -- fine if you're running it unmodified, but if
+# you've forked or patched the code, point this at *your* copy instead.
+VITE_SOURCE_URL=https://github.com/ds-ksmith/DS-Chat

frontend/README.md

@@ -112,7 +112,7 @@ src/
     LoginPage.tsx, SignupPage.tsx, ForgotPasswordPage.tsx, ResetPasswordPage.tsx
     ChatShellPage.tsx, AdminPage.tsx, HelpPage.tsx
 
-  styles/tokens.css          design tokens (DarkSingularity theme: colors, spacing, etc.)
+  styles/tokens.css          design tokens (default theme: colors, spacing, etc.)
   sw.ts                      custom service worker (injectManifest): app-shell
                                precache + NetworkFirst runtime caching, push/notificationclick
                                handlers, SKIP_WAITING messaging for the update-prompt flow

frontend/package.json

@@ -1,7 +1,7 @@
 {
   "name": "frontend",
   "private": true,
-  "version": "2026.9.3",
+  "version": "2026.9.23",
   "license": "AGPL-3.0-or-later",
   "type": "module",
   "scripts": {

frontend/src/components/AboutModal.tsx

@@ -10,8 +10,10 @@ interface AboutModalProps {
 // users remotely through a computer network, you should also make sure
 // that it provides a way for users to get its source... its interface
 // could display a 'Source' link" -- this modal is that link, not just a
-// courtesy credits screen.
+// courtesy credits screen. Deliberately not a hardcoded URL: whoever
-const SOURCE_URL = 'https://git.darksingularity.org/DarkSingularity/ds-chat'
+// deploys this needs to point it at *their* copy of the repo (including
+// any modifications), not the upstream project -- see frontend/.env.example.
+const SOURCE_URL = import.meta.env.VITE_SOURCE_URL as string | undefined
 
 export function AboutModal({ onClose }: AboutModalProps) {
   return (
@@ -39,11 +41,13 @@ export function AboutModal({ onClose }: AboutModalProps) {
           </a>
           .
         </p>
-        <p className="about-modal-line">
+        {SOURCE_URL && (
-          <a href={SOURCE_URL} target="_blank" rel="noopener noreferrer">
+          <p className="about-modal-line">
-            Source code
+            <a href={SOURCE_URL} target="_blank" rel="noopener noreferrer">
-          </a>
+              Source code
-        </p>
+            </a>
+          </p>
+        )}
 
         <div className="modal-actions" style={{ marginTop: '1rem' }}>
           <button type="button" className="btn-secondary" onClick={onClose}>

frontend/src/ws/useChatSocket.ts

@@ -10,6 +10,13 @@ interface UseChatSocketOptions {
 const RECONNECT_BASE_DELAY_MS = 1000
 const RECONNECT_MAX_DELAY_MS = 30000
 
+// #76: the backend pings every 30s (WS_PING_INTERVAL_SECONDS in chat.py) --
+// this needs to comfortably tolerate one missed ping plus ordinary network
+// jitter before declaring the connection dead, not fire on the very first
+// late beat.
+const ZOMBIE_TIMEOUT_MS = 65000
+const ZOMBIE_CHECK_INTERVAL_MS = 10000
+
 const desktopMode = isDesktopNotificationsSupported()
 
 // Room join/leave (live message delivery) depends only on visibility --
@@ -51,6 +58,16 @@ export function useChatSocket({ onUnauthenticated }: UseChatSocketOptions) {
   // live WebSocket delivery the user can't actually see will do the job.
   const desiredRoomsRef = useRef(new Set<string>())
   const isVisibleRef = useRef(isVisible())
+  // #76: last time *anything* arrived on the socket (a real message, a
+  // "ping", doesn't matter which) -- the only signal that a connection
+  // sitting at readyState OPEN is actually still alive rather than a
+  // zombie. Without this, a connection that dies without ever sending a
+  // close frame (laptop sleep, a NAT silently dropping an idle mapping)
+  // looks identical to a healthy-but-quiet one: onclose never fires, so the
+  // already-correct reconnect+rejoin logic below never runs, and new
+  // messages just stop arriving until something unrelated (e.g. switching
+  // rooms, which refetches history over plain REST) papers over it.
+  const lastActivityRef = useRef(Date.now())
 
   const sendRoomFrame = useCallback((type: 'join' | 'leave', roomId: string) => {
     const ws = socketRef.current
@@ -99,6 +116,7 @@ export function useChatSocket({ onUnauthenticated }: UseChatSocketOptions) {
         if (hasConnectedBefore) checkForUpdate()
         hasConnectedBefore = true
         reconnectDelay = RECONNECT_BASE_DELAY_MS
+        lastActivityRef.current = Date.now()
         setConnected(true)
         // Re-join whatever rooms were joined before a reconnect -- the
         // server has no memory of a dropped connection's prior state. Only
@@ -122,7 +140,17 @@ export function useChatSocket({ onUnauthenticated }: UseChatSocketOptions) {
 
       ws.onmessage = (event) => {
         if (socketRef.current !== ws) return
-        const envelope = JSON.parse(event.data) as ServerEnvelope
+        lastActivityRef.current = Date.now()
+        const parsed = JSON.parse(event.data)
+        // #76: the server's heartbeat -- purely transport-level, not a
+        // domain event, so it's answered and swallowed right here instead
+        // of being forwarded to subscribers (ServerEnvelope's own type
+        // doesn't include it for exactly that reason).
+        if (parsed.type === 'ping') {
+          ws.send(JSON.stringify({ type: 'pong' }))
+          return
+        }
+        const envelope = parsed as ServerEnvelope
         for (const handler of subscribersRef.current) handler(envelope)
       }
 
@@ -143,10 +171,9 @@ export function useChatSocket({ onUnauthenticated }: UseChatSocketOptions) {
         if (stopped) return
 
         // Unexpected close -- a deploy restarting the app server, a brief
-        // network blip, or (absent any app-level ping/pong) an idle
+        // network blip, or an idle connection getting recycled by a reverse
-        // connection getting recycled by a reverse proxy in front of it.
+        // proxy in front of it. Retry with exponential backoff instead of
-        // Retry with exponential backoff instead of leaving the chat
+        // leaving the chat silently dead until the user manually reloads.
-        // silently dead until the user manually reloads.
         reconnectTimer = setTimeout(connect, reconnectDelay)
         reconnectDelay = Math.min(reconnectDelay * 2, RECONNECT_MAX_DELAY_MS)
       }
@@ -154,9 +181,21 @@ export function useChatSocket({ onUnauthenticated }: UseChatSocketOptions) {
 
     connect()
 
+    // #76: catches the case onclose can't -- a connection that dies without
+    // ever sending a close frame at all (readyState stays OPEN forever) is
+    // otherwise invisible to this hook. Forcing a close here just routes it
+    // through the exact same onclose/reconnect/rejoin path as a normal
+    // disconnect, rather than needing separate recovery logic of its own.
+    const zombieCheckTimer = setInterval(() => {
+      if (Date.now() - lastActivityRef.current > ZOMBIE_TIMEOUT_MS) {
+        socketRef.current?.close()
+      }
+    }, ZOMBIE_CHECK_INTERVAL_MS)
+
     return () => {
       stopped = true
       if (reconnectTimer) clearTimeout(reconnectTimer)
+      clearInterval(zombieCheckTimer)
       socketRef.current?.close()
       socketRef.current = null
     }