familysync/.planning/phases/09-faster-write-back/09-VERIFICATION.md

phase, verified, status, score, overrides_applied

phase	verified	status	score	overrides_applied
09-faster-write-back	2026-06-12T17:07:00Z	passed	5/5 must-haves verified	0

Phase 09: Faster Write-Back Verification Report

Phase Goal: A created, edited, or deleted event reaches Fastmail within ~1-2 seconds (event-driven outbox drain) instead of waiting up to ~15s for the next interval tick — with every existing durability guarantee intact. Verified: 2026-06-12T17:07:00Z Status: passed Re-verification: No — initial verification

Goal Achievement

Observable Truths

#	Truth	Status	Evidence
1	After creating/editing/deleting an event, the change is signalled to drain on enqueue (not waited-for on the interval) — the drain fires promptly, not on the 15s tick.	VERIFIED	signalOutboxDrain() called at all 4 enqueue sites in events.ts (lines 310, 434, 450, 525). Test SC-1 in outboxWorker.test.ts confirms drain fires via EventEmitter signal without advancing any timer.
2	The route handler still returns an optimistic 202 immediately and never makes a CalDAV call inline — the signal is fire-and-forget (never awaited).	VERIFIED	No await signalOutboxDrain in events.ts. All 4 sites call signalOutboxDrain(); then immediately return c.json(..., 202). events.test.ts (23 tests) confirms 202 + no-inline-CalDAV contract still holds.
3	Edit-as-move still writes the new event before deleting the old one (create-before-delete preserved); the signal fires AFTER the db.transaction resolves, never inside it.	VERIFIED	events.ts line 410 opens await db.transaction(async (tx) => { ... }); closing at line 432. signalOutboxDrain() appears at line 434 — after the await db.transaction(...) statement, not inside the callback. Confirmed: no signalOutboxDrain between the two tx.insert calls.
4	No duplicate CalDAV PUTs for the same outbox row when signal and the 15s fallback overlap (exactly-once per uid preserved via the isDraining guard + drainRequested trailing-re-drain).	VERIFIED	scheduleOutboxDrain checks if (isDraining) { drainRequested = true; return; } before calling runOutboxDrain(). Test D-07 (Test C) verifies two concurrent scheduleOutboxDrain() calls result in createCalendarEvent called exactly once. Test D-05 (Test B) verifies mid-drain signals collapse to exactly one trailing re-drain.
5	The 15s setInterval fallback still runs and recovers missed rows.	VERIFIED	startOutboxWorker in outboxWorker.ts line 857: setInterval(() => { scheduleOutboxDrain(); }, 15 * 1000) — interval length unchanged, body routes through scheduleOutboxDrain wrapper.

Score: 5/5 truths verified

Required Artifacts

Artifact	Expected	Status	Details
apps/api/src/lib/outboxTrigger.ts	Zero-dependency EventEmitter signal (signalOutboxDrain, onOutboxDrain)	VERIFIED	Exists. Imports only node:events. Exports signalOutboxDrain and onOutboxDrain. No setMaxListeners. No internal project imports.
apps/api/src/broker/outboxWorker.ts	scheduleOutboxDrain + drainRequested + initOutboxTrigger	VERIFIED	Exports scheduleOutboxDrain, initOutboxTrigger. Declares let drainRequested = false at line 172. drainRequested = false reset precedes recursive scheduleOutboxDrain() call (line 199 before 200 — Pitfall 3 correct).
apps/api/src/routes/events.ts	Four post-commit signalOutboxDrain() publish sites	VERIFIED	Exactly 4 calls (lines 310, 434, 450, 525). Import at line 37. None awaited. None inside transaction callback or catch blocks.
apps/api/src/index.ts	initOutboxTrigger() wired under isMainModule(), after startOutboxWorker()	VERIFIED	Line 138: startOutboxWorker(). Line 139: initOutboxTrigger(); // subscribe drain signal listener (D-01). Both inside the if (isMainModule()) block.
apps/api/tests/broker/outboxWorker.test.ts	Trigger-wiring test block (SC-1, D-05, D-07) — 3 new tests	VERIFIED	describe('scheduleOutboxDrain — trigger wiring (D-09)', ...) block at line 747 with beforeAll(() => { initOutboxTrigger(); }) and 3 tests. All 30 outboxWorker tests pass.

Key Link Verification

From	To	Via	Status	Details
outboxWorker.ts (initOutboxTrigger)	outboxTrigger.ts (onOutboxDrain)	onOutboxDrain(() => scheduleOutboxDrain())	WIRED	Line 845: onOutboxDrain(() => scheduleOutboxDrain()). Import at line 39.
outboxWorker.ts (scheduleOutboxDrain)	outboxWorker.ts (runOutboxDrain)	isDraining guard + drainRequested trailing-re-drain	WIRED	Lines 187-203: guard checks isDraining, calls runOutboxDrain(), finally resets drainRequested before recursive call.
routes/events.ts	outboxTrigger.ts (signalOutboxDrain)	import + call after each enqueue commit	WIRED	Import at line 37. 4 call sites verified present and not awaited.
index.ts (isMainModule block)	outboxWorker.ts (initOutboxTrigger)	initOutboxTrigger() after startOutboxWorker()	WIRED	Lines 138-139 inside isMainModule() guard.
startOutboxWorker setInterval	scheduleOutboxDrain	bare scheduleOutboxDrain() call in 15s interval	WIRED	Lines 857-859: setInterval(() => { scheduleOutboxDrain(); }, 15 * 1000).

Data-Flow Trace (Level 4)

Not applicable — phase adds a signal/trigger path, not a data-rendering path. The signal carries no payload; it triggers an existing drain that queries the DB for pending rows. The drain's data path (outbox rows → CalDAV) is unchanged and was verified in prior phases.

Behavioral Spot-Checks

Behavior	Command	Result	Status
SC-1: signalOutboxDrain() triggers drain without timer advance	npx vitest run tests/broker/outboxWorker.test.ts — Test A	30/30 passed	PASS
D-05: mid-drain signals collapse to one trailing re-drain	Test B in same run	30/30 passed	PASS
D-07: concurrent scheduleOutboxDrain() calls are exactly-once	Test C in same run	30/30 passed	PASS
202 + no-inline-CalDAV route contract preserved	npx vitest run tests/routes/events.test.ts	23/23 passed	PASS
tsc clean across all phase-9 files	npx tsc --noEmit	No output (clean)	PASS

Probe Execution

No conventional scripts/*/tests/probe-*.sh probes declared or found for this phase.

Requirements Coverage

Requirement	Source Plan	Description	Status	Evidence
CAL-15	09-01-PLAN.md, 09-02-PLAN.md	Event reaches Fastmail within ~2s (event-driven drain) instead of up to ~15s, while preserving optimistic-202 and all outbox durability guarantees.	SATISFIED	signalOutboxDrain() fires immediately post-enqueue. SC-1 test confirms no timer advance needed. isDraining guard + drainRequested preserve exactly-once. 15s fallback intact. REQUIREMENTS.md marks CAL-15 as Complete.

Anti-Patterns Found

No debt markers (TBD/FIXME/XXX/TODO/HACK/PLACEHOLDER) found in any phase-9 modified file. No stub patterns found. No return null, empty handlers, or hardcoded empty data in the signal path.

Human Verification Required

None. The phase goal (latency reduction via event-driven drain) is fully verifiable through automated tests and static code inspection:

• SC-1 (no 15s wait): automated by the trigger-wiring Vitest test using setImmediate flush — no stopwatch needed.
• D-04 (fire-and-forget): verified by static grep — no await signalOutboxDrain anywhere.
• D-03 (signal after transaction): verified by static line-number inspection — signalOutboxDrain() at line 434 is after await db.transaction(...) closes at line 432.
• Fallback interval: verified by reading the startOutboxWorker body.

Gaps Summary

No gaps. All 5 must-have truths are VERIFIED with direct codebase evidence:

1. All 4 enqueue sites in events.ts call signalOutboxDrain() post-commit, pre-202.
2. No call is awaited; the signal is synchronous EventEmitter emit.
3. The edit-as-move signal is provably outside the transaction callback at the source level.
4. The isDraining guard + drainRequested boolean collapses concurrent/mid-drain signals correctly; verified by 2 dedicated automated tests.
5. The 15s setInterval fallback routes through scheduleOutboxDrain() at the same 15-second cadence.

CAL-15 is marked Complete in REQUIREMENTS.md (line 78) and all its behavioral guarantees are implemented and tested.

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Verified: 2026-06-12T17:07:00Z Verifier: Claude (gsd-verifier)