Before starting Layer 4 — casehub-ledger integration — I wanted to close three backlog items that had been accumulating since Layer 3. None were blocking, but they were the kind of drift that compounds: inconsistent documentation, seeding code copied six times across test classes, no slice plan for a project now three layers deep.

LAYER-LOG.md had two separate conventions for navigation metadata. Layer 1 had **Issue:** and **Navigation:** inline in the header block. Layers 2 and 3 had ### Navigation subsections buried at the bottom of each entry. All seven layers are now standardised on the header format, and the stale Layer 3 “Open follow-up” section — still listing issues #16, #17, and #18 from last session, all closed — got removed.

Trivial individually. Collectively they make the log navigable.

Defining the vertical slices

The SIAL protocol requires a Vertical Slice Index at the top of LAYER-LOG.md — user-visible capabilities, sequenced by dependency. I’d been building layers without one, which meant the log told you how each integration was done but not what the system could actually do at each milestone.

Six slices for casehub-life:

Slice Capability
S1 Tasks with SLA deadlines; household-admin escalated on breach (Layers 1–2)
S2 Formal COMMAND/RESPONSE commitments with Watchdog follow-up (+ Layer 3)
S3 Tamper-evident Merkle audit + GDPR Art.17 erasure (+ Layer 4)
S4 Multi-step CasePlanModel workflows (+ Layer 5)
S5 Trust-weighted agent routing (+ Layer 6)
S6 OpenClaw skill integration (+ Layer 7)

Writing the capability description for S2 forced me to be precise about something I’d been glossing over. Three commitment modes — family delegation, contractor follow-up, oversight gate — look similar in the docs but have genuinely different mechanics. Delegation requires acknowledged RESPONSE. Contractor gets Watchdog follow-up if no response arrives. Oversight gates are different: no WorkItem exists until the household-admin RESPONSE arrives. There is nothing to block — creation is deferred, not held up.

Claude caught this during code review. I’d written “financial-oversight gates block WorkItem creation until household-admin approves.” That’s wrong — “block” implies something in flight. The correct description is “defer WorkItem creation — no task exists until RESPONSE is received.” One word change, but it shifts how you’d implement the pattern.

The arch pattern column for pending slices (S3–S6) presented a similar question. I wanted to label S3 as + Interceptor since casehub-ledger uses ProvenanceCaptureInterceptor internally. But the pattern the consumer demonstrates is calling a port — Hexagonal — not implementing the interceptor. The interceptor is a ledger-internal concern. The right pattern label for S3 will be clear once Layer 4 is built. For now the cell shows 🔲. Honest placeholder.

The seeding tax

Six @QuarkusTest classes all had their own seedTemplates() + seedIfAbsent() implementations. Same four templates, same field values, five different UUID ranges, and a priority discrepancy: life-escalation was MEDIUM in five classes and HIGH in one.

We extracted it into LifeTestFixtures — a final utility class with two static methods: seedStandardTemplates() and seedEscalationTemplate(). Static methods inherit the active JTA transaction from @BeforeEach @Transactional, so no CDI injection is needed. Canonical UUIDs 001–004. Idempotency guard by template name. life-escalation standardised to HIGH, which is what the escalation semantic actually requires.

During review Claude flagged the t.createdAt = Instant.now() line in the fixture helper — cargo code we’d been copying across three layers. WorkItemTemplate has a @PrePersist method that sets createdAt (and id, if null) automatically. Every fixture had been setting createdAt explicitly for nothing. The only reason to set id explicitly is to get deterministic UUIDs for test analysis — which we still do. The createdAt line was just noise from the first fixture ever written, faithfully copied ever since.

61 tests pass. The CLAUDE.md testing table now references LifeTestFixtures instead of the old per-class seedIfAbsent pattern.

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