# Pre-deployment Fix Wave Report

Date: 2026-07-14
Worktree: `/home/chirone/ThothII/.worktrees/activity-log-cte-layout`
Base: `e5366d14a6da8fb331d94be60b8929cefb1fe3e0`

## Outcome

All three reviewed findings are implemented in one coherent backend/frontend wave:

1. Resume leaves the prior selection, Zustand state, document panel, and EventSource untouched
   until `POST /resume` succeeds. Cold Resume changes state and reconnects only after backend
   clear/rebind; already-active same-session Resume preserves the existing binding; failure is a
   no-op apart from the fixed toast.
2. SSE uses monotonically increasing per-session ids, cursor-filtered replay, native and manual
   reconnect cursors, id continuity across `hub.clear`, and descriptor-id pending-gate
   idempotence at both backend and frontend layers.
3. Generic Pi system events and readiness errors are projected through explicit public
   allowlists. Sentinel URLs, paths, tokens, stderr, commands, and extra fields do not reach HTTP
   or SSE.

No harness, workflow, persistence, model, CTE viewer, CTE card, or shared Card file changed.

## Interfaces

- Frontend `resumeSession(id)` now returns
  `Promise<{ id: string; alreadyActive: boolean }>` via `ResumeSessionResult`.
- Backend successful Resume always returns the same shape:
  - running/waiting runtime: `{ id, alreadyActive: true }`
  - validated cold runtime: `{ id, alreadyActive: false }`
- `SseHub.publish(sessionId, event, data): number` returns the assigned SSE id.
- `SseHub.subscribe(sessionId, send, { afterId, pending })` calls
  `send(event, data, id)` for replay/live frames with `id > afterId`.
- `GET /sessions/:id/events` accepts native `Last-Event-ID` and manual
  `?lastEventId=<integer>`; when both are valid it uses the greater cursor.
- Every emitted SSE frame is `id: <n>\nevent: <name>\ndata: <json>\n\n`.
- Public readiness failure is exactly:
  `Session services are not ready. Check configuration and connectivity, then try again.`
- Generic Pi system events are exactly `{ type: "system_event", event }`, and `event` must be a
  non-empty string.

## Files

Backend production:

- `backend/src/bridge/session-bridge.ts`
- `backend/src/routes/sessions.ts`
- `backend/src/sse/sse-hub.ts`

Backend tests:

- `backend/test/routes-sessions.test.ts`
- `backend/test/session-bridge.test.ts`
- `backend/test/sse-hub.test.ts`
- `backend/test/sse-route.test.ts` (new)

Frontend production/support:

- `frontend/src/api/sessions.ts`
- `frontend/src/api/types.ts`
- `frontend/src/shell/AppShell.tsx`
- `frontend/src/store/sessionStore.ts`
- `frontend/src/stream/useSessionStream.ts`
- `frontend/src/test/fakeEventSource.ts`

Frontend tests:

- `frontend/src/api/sessions.test.ts`
- `frontend/src/shell/AppShell.session-mgmt.test.tsx`
- `frontend/src/store/sessionStore.test.ts`
- `frontend/src/stream/useSessionStream.test.tsx`

## TDD RED/GREEN evidence

### 1. Backend Resume result and client-boundary allowlists

RED command:

```text
cd backend && npx vitest run test/routes-sessions.test.ts test/session-bridge.test.ts
```

RED output (exit 1):

```text
Test Files  2 failed (2)
Tests       6 failed | 35 passed (41)

expected { id: 's1' } to deeply equal { id: 's1', alreadyActive: false }
expected raw readiness URL/token/path to equal the fixed public message
expected three raw generic system events to equal [{ type: 'system_event', event: 'session_exit' }]
```

GREEN command:

```text
cd backend && npx vitest run test/routes-sessions.test.ts test/session-bridge.test.ts
```

GREEN output (exit 0):

```text
✓ test/session-bridge.test.ts (14 tests)
✓ test/routes-sessions.test.ts (27 tests)
Test Files  2 passed (2)
Tests       41 passed (41)
```

### 2. Backend exact-once SseHub and route framing

RED command:

```text
cd backend && npx vitest run test/sse-hub.test.ts test/sse-route.test.ts
```

RED output (exit 1):

```text
Test Files  2 failed (2)
Tests       7 failed (7)

expected [undefined, undefined, undefined] to deeply equal [1, 2, 3]
expected unconditional replay not to contain "one" / "two"
expected one buffered pending gate, received replay plus a second pending emission
```

GREEN command:

```text
cd backend && npx vitest run test/sse-hub.test.ts test/sse-route.test.ts
```

GREEN output (exit 0):

```text
✓ test/sse-hub.test.ts (4 tests)
✓ test/sse-route.test.ts (3 tests)
Test Files  2 passed (2)
Tests       7 passed (7)
```

### 3. Frontend cursor tracking and gate idempotence

RED command:

```text
cd frontend && npx vitest run src/stream/useSessionStream.test.tsx src/store/sessionStore.test.ts
```

RED output (exit 1):

```text
Test Files  2 failed (2)
Tests       2 failed | 28 passed (30)

expected /sessions/s1/events to be /sessions/s1/events?lastEventId=7
expected duplicate gate pendingWidget to remain null, received gate-1
```

GREEN command:

```text
cd frontend && npx vitest run src/stream/useSessionStream.test.tsx src/store/sessionStore.test.ts
```

GREEN output (exit 0):

```text
✓ src/store/sessionStore.test.ts (23 tests)
✓ src/stream/useSessionStream.test.tsx (7 tests)
Test Files  2 passed (2)
Tests       30 passed (30)
```

### 4. Frontend typed Resume and AppShell ordering/preservation

Typed API RED command:

```text
cd frontend && npx tsc -b
```

Typed API RED output (exit 1):

```text
src/api/sessions.test.ts(43,9): error TS2322: Type 'void' is not assignable to type
'{ id: string; alreadyActive: boolean; }'.
```

Lifecycle RED command:

```text
cd frontend && npx vitest run src/api/sessions.test.ts src/shell/AppShell.session-mgmt.test.tsx
```

Lifecycle RED output (exit 1):

```text
✓ src/api/sessions.test.ts (9 tests)
❯ src/shell/AppShell.session-mgmt.test.tsx (15 tests | 4 failed)
Test Files  1 failed | 1 passed (2)
Tests       4 failed | 20 passed (24)

already-active same-session Resume created two EventSources instead of one
deferred cold Resume closed the document panel before POST completion
failed same-session Resume closed the prior EventSource
failed Resume with no active session opened an EventSource
```

GREEN commands:

```text
cd frontend && npx vitest run src/api/sessions.test.ts src/shell/AppShell.session-mgmt.test.tsx
cd frontend && npx tsc -b
```

GREEN output (exit 0):

```text
✓ src/api/sessions.test.ts (9 tests)
✓ src/shell/AppShell.session-mgmt.test.tsx (15 tests)
Test Files  2 passed (2)
Tests       24 passed (24)
TypeScript: no output, exit 0
```

The AppShell cold-reconnect test additionally proves that the old source accepts an event while
Resume is pending, the replacement URL carries `lastEventId=8`, the replacement receives one
post-resume transcript/activity row, and two deliveries of the same descriptor id yield one gate.

## Affected verification

Backend command:

```text
cd backend && npx vitest run test/routes-sessions.test.ts test/session-bridge.test.ts \
  test/sse-hub.test.ts test/sse-route.test.ts test/health.test.ts test/e2e-f1.test.ts
```

Output (exit 0):

```text
Test Files  6 passed (6)
Tests       52 passed (52)
```

Backend typecheck:

```text
cd backend && npx tsc --noEmit -p .
```

Output: no output, exit 0.

Frontend command:

```text
cd frontend && npx vitest run src/api/sessions.test.ts src/store/sessionStore.test.ts \
  src/stream/useSessionStream.test.tsx src/shell/AppShell.session-mgmt.test.tsx \
  src/shell/CentralStatus.test.tsx src/shell/ModelActivityPanel.test.tsx \
  src/shell/f1-loop.test.tsx src/shell/AppShell.new-session.test.tsx
```

Output (exit 0):

```text
Test Files  8 passed (8)
Tests       74 passed (74)
```

Frontend typecheck:

```text
cd frontend && npx tsc -b
```

Output: no output, exit 0.

## Full verification

Backend full suite:

```text
cd backend && npx vitest run
```

```text
Test Files  22 passed (22)
Tests       177 passed (177)
```

Frontend full suite:

```text
cd frontend && npx vitest run
```

```text
Test Files  43 passed (43)
Tests       271 passed (271)
```

Backend production build:

```text
cd backend && npm run build
> tsc -p tsconfig.json
exit 0
```

Frontend production build:

```text
cd frontend && npm run build
> tsc -b && vite build
✓ 4835 modules transformed.
✓ built in 8.25s
exit 0
```

## Integrated re-review closure (2026-07-15)

This section supersedes the earlier cold same-session assertion that the replacement URL carries
`lastEventId=8`. That behavior was correct only while the backend process and its in-memory id
sequence survived. A restarted backend begins a fresh sequence, so a successful cold Resume now
explicitly discards the browser's cursor before replacing the EventSource.

All four integrated re-review findings are closed:

1. `AppShell` passes a dedicated cursor-reset epoch to `useSessionStream`. A cold same-session
   Resume increments it only after `alreadyActive: false`; a high cursor such as `901` is omitted
   from the replacement URL and fresh low-id events/gates are consumed. An already-active
   same-session Resume still preserves its source, cursor, and store.
2. `useSessionStream` no longer mutates the cursor ref during render. Effect setup resets cursor
   state on session/reset-epoch changes, callbacks are guarded by a captured active-source
   identity, and cleanup clears only its own active identity. A queued event from the replaced
   source cannot write the new store or poison its next reconnect URL.
3. Backend Resume is serialized per session and rechecks runtime state inside the lock. Manifest,
   readiness, and reopen validation precede the transport commit. Idle/failed replacement creates
   and binds the new runtime before `hub.clear`, which occurs synchronously immediately before the
   first `Resuming session` publish. Reopen/create failure returns exactly
   `Session could not be resumed. Check configuration and connectivity, then try again.`, keeps the
   prior hub buffer/subscribers attached, and does not expose exception sentinels. Concurrent calls
   perform one cold start and the waiter returns `alreadyActive: true`.
4. `SseHub.forget(id)` removes subscribers, buffered events, and the last id. Permanent session
   DELETE invokes it after disk deletion; ordinary close and Resume continue to use `clear`, which
   preserves the id sequence.

### Re-review files

Production:

- `backend/src/pi/pi-process-manager.ts`
- `backend/src/routes/sessions.ts`
- `backend/src/sse/sse-hub.ts`
- `frontend/src/shell/AppShell.tsx`
- `frontend/src/stream/useSessionStream.ts`

Tests/support:

- `backend/test/pi-process-manager.test.ts`
- `backend/test/routes-sessions.test.ts`
- `backend/test/sse-hub.test.ts`
- `frontend/src/shell/AppShell.session-mgmt.test.tsx`
- `frontend/src/stream/useSessionStream.test.tsx`
- `frontend/src/test/fakeEventSource.ts`

### Re-review TDD RED/GREEN evidence

Frontend RED command:

```text
cd frontend && npx vitest run src/stream/useSessionStream.test.tsx \
  src/shell/AppShell.session-mgmt.test.tsx
```

RED output (exit 1):

```text
Test Files  2 failed (2)
Tests       3 failed | 21 passed (24)

reset epoch: expected the old source to close, received false
cold same-session: expected /sessions/s1/events, received ?lastEventId=901
stale source: expected an empty transcript, received "stale session one"
```

Frontend GREEN command:

```text
cd frontend && npx vitest run src/stream/useSessionStream.test.tsx \
  src/shell/AppShell.session-mgmt.test.tsx
cd frontend && npx tsc -b
```

GREEN output (exit 0):

```text
Test Files  2 passed (2)
Tests       24 passed (24)
TypeScript: no output, exit 0
```

Backend RED command:

```text
cd backend && npx vitest run test/sse-hub.test.ts test/routes-sessions.test.ts
```

RED output (exit 1):

```text
Test Files  2 failed (2)
Tests       8 failed | 28 passed (36)

three Resume ordering assertions observed clear before reopen/create
reopen and create sentinels escaped as raw HTTP 500 responses
the concurrent waiter cold-started again instead of returning alreadyActive: true
SseHub.forget was absent and DELETE did not invoke permanent cleanup
```

Backend GREEN command:

```text
cd backend && npx vitest run test/sse-hub.test.ts test/routes-sessions.test.ts
cd backend && npx tsc --noEmit -p .
```

GREEN output (exit 0):

```text
Test Files  2 passed (2)
Tests       36 passed (36)
TypeScript: no output, exit 0
```

The failure tests publish a post-failure probe through the same hub and prove that a subscriber
attached before either reopen or create rejection still receives it. The concurrency test overlaps
two same-id requests behind a deferred reopen and proves one manifest/readiness/reopen/create/clear
sequence.

### Initial re-review verification (before independent-review hardening)

```text
cd backend && npx vitest run
Test Files  22 passed (22)
Tests       182 passed (182)

cd frontend && npx vitest run
Test Files  43 passed (43)
Tests       273 passed (273)

cd backend && npm run build
> tsc -p tsconfig.json
exit 0

cd frontend && npm run build
> tsc -b && vite build
✓ 4835 modules transformed.
✓ built in 8.46s
exit 0
```

`git diff --check` produced no output (exit 0). The frontend build retains its pre-existing
large-chunk warning; no new build or type errors were introduced.

Final whitespace verification:

```text
git diff --check
no output, exit 0
```

## Self-review

- Resume sequencing: reopen and runtime binding precede backend `clear` and HTTP success; frontend
  state mutation and cursor-reset epoch follow it. Failure catch only emits fixed UI copy.
- Already active: same-session returns before reset/generation/manifest repaint; different session
  resets the single-session store and binds the new id only after success.
- SSE exact-once: ids are transport identity, not content hashes; replay is strictly `id > cursor`;
  `clear` retains the counter; pending gate matching uses only descriptor id.
- Cursor behavior: hook tracks `MessageEvent.lastEventId`, carries it only to an ordinary same-id
  generation, and resets it on session-id/cold-runtime epoch change. Native EventSource reconnect
  remains supported by the route header.
- Gate defense: the Zustand set survives pending clear but resets with the session store.
- Client boundary: raw `ensure.error` is unused in public responses; generic Pi system events are
  reconstructed rather than spread; frontend type mirrors the two-field event.
- Scope: `git diff` contains no CTE/Card/harness/workflow/persistence/model changes. Four pre-existing
  modified `.superpowers/sdd/{progress,task-2-report,task-3-report,task-4-report}.md` files are user
  work and are excluded from staging.

## Remaining concerns

- The 200-event SSE ring limit remains intentional. A brand-new page can reconstruct only retained
  backlog; an in-memory same-session reconnect is exact-once from its cursor.
- Per-session sequence counters remain in backend memory after `clear` by design so later in-process
  cold same-id Resume cannot reuse ids. Permanent DELETE removes the counter via `forget`.
- Frontend tests still print pre-existing MSW unhandled-request and React ref/`act` warnings even
  though all 276 tests pass. The frontend production build still reports pre-existing large chunk
  warnings. Neither warning class was introduced or expanded by this change.
- No live Pi/DWH smoke was run; this wave changes only REST/SSE/frontend lifecycle boundaries and
  is covered by fake-Pi, live Fastify SSE, component, full-suite, typecheck, and production-build
  gates.

## Independent-review hardening

The required independent review was run repeatedly against the uncommitted diff. Its first pass
found four Important lifecycle edges beyond the integrated findings: queued old-runtime callbacks,
post-spawn construction cleanup, concurrent frontend Resume completions, and the passive-effect
commit window. Its second pass confirmed those fixes and identified one remaining Important
retention issue in the new runtime-identity map. The final pass reported no Critical, Important, or
Minor findings and assessed the diff ready to merge.

The resulting hardening is:

- Runtime bridge callbacks are gated by the bound runtime identity. Replacement, close, and DELETE
  invalidate the old identity, so queued old events cannot publish or call `failSession`. An active
  runtime removed by the manager can still publish its complete public failure sequence; after the
  terminal unmanaged `agent_end`, its binding is released and later events are rejected.
- `PiProcessManager` kills the spawned child and removes any registered map entry if either
  spawn-boundary stderr setup or later RPC/bridge/map initialization throws.
- Resume completion compares against synchronously maintained current active-session identity.
  Concurrent `alreadyActive: false` then `alreadyActive: true` results preserve the cold source,
  cursor, store, and replayed gate.
- Stream source replacement uses a layout effect. A deterministic later-layout-effect test delivers
  a queued old event inside the former commit-to-passive-cleanup window and proves it is ignored.
- Cursor tests cover both a restarted backend's fresh low ids and an in-process hub's preserved high
  ids followed by a cursor-bearing ordinary reconnect.

### Hardening TDD RED/GREEN evidence

Backend identity/construction RED command:

```text
cd backend && npx vitest run test/pi-process-manager.test.ts test/routes-sessions.test.ts
```

```text
Test Files  2 failed (2)
Tests       3 failed | 69 passed (72)

post-spawn reader initialization did not kill the child
replaced and deleted runtime callbacks still called failSession/published
```

Additional spawn-boundary and terminal-release RED checks:

```text
cd backend && npx vitest run test/pi-process-manager.test.ts \
  -t "spawn boundary initialization"
Tests       1 failed | 38 skipped (39)

cd backend && npx vitest run test/routes-sessions.test.ts -t "terminal sequence"
Tests       1 failed | 34 skipped (35)
```

Frontend concurrency/layout RED command:

```text
cd frontend && npx vitest run src/stream/useSessionStream.test.tsx \
  src/shell/AppShell.session-mgmt.test.tsx
```

```text
Test Files  2 failed (2)
Tests       2 failed | 25 passed (27)

the later-layout-effect event wrote "commit-window stale text"
the false→true completion pair erased pending gate "cold-gate"
```

Final focused GREEN commands:

```text
cd backend && npx vitest run test/pi-process-manager.test.ts \
  test/routes-sessions.test.ts test/sse-hub.test.ts
cd backend && npx tsc --noEmit -p .

Test Files  3 passed (3)
Tests       79 passed (79)
TypeScript: no output, exit 0

cd frontend && npx vitest run src/stream/useSessionStream.test.tsx \
  src/shell/AppShell.session-mgmt.test.tsx
cd frontend && npx tsc -b

Test Files  2 passed (2)
Tests       27 passed (27)
TypeScript: no output, exit 0
```

### Final full verification after review hardening

```text
cd backend && npx vitest run
Test Files  22 passed (22)
Tests       188 passed (188)

cd frontend && npx vitest run
Test Files  43 passed (43)
Tests       276 passed (276)

cd backend && npm run build
> tsc -p tsconfig.json
exit 0

cd frontend && npm run build
> tsc -b && vite build
✓ 4835 modules transformed.
✓ built in 8.47s
exit 0
```

The final frontend run retains the repository's pre-existing MSW/ref/`act` warnings, and the build
retains the pre-existing large-chunk warning. No test, typecheck, or build failures remain.