# KBN-101 — B1/B2 Envelope A (v6, FINAL) — Declarative Sink-RBAC + Per-Role Credential/Connection-Selection + RLS Write-Source (INSERT tenant-bound, single-compound-or-RESTRICTIVE composition) + Sink-Resident User-Override + Read/USING Enforcement

**Ratification status:** RATIFIED — part of the frozen SSOT as of this PR (KBN-101 Envelope A, landed **FORM A — apply-in-place**). This is the converged **v6** envelope, ratified as the authoritative record of the **rc.20** contract amendment now inlined into [`KBN-101-DB-ROLE-SPLIT.md`](./KBN-101-DB-ROLE-SPLIT.md) §4/§10, [`SHARED-CONTRACT.md`](./SHARED-CONTRACT.md) (`### 1.0.0-rc.20`), and [`MISSION-MANIFEST.md`](./MISSION-MANIFEST.md) §10.

**Ratification lineage (authoritative):** Jason B1 ruling (2026-07-20T23:08Z) + Mos coordinator **OPTION A** (home the layer) + **Mos Q1** ruling (TIER-LEVEL) + **Mos Q2** ruling (RLS `WITH CHECK` AUTHORIZED, two mandatory conditions — `ENABLE`/`FORCE ROW LEVEL SECURITY` as the terminal migration step, and non-owner rung roles) + **Gate A** (`a11a1e2c`) + **Gate B** (`a6aac2cd`).

> **Ratification note.** The sections below are the converged v6 envelope text, retained **VERBATIM** for traceability. Their design-time framing — e.g. "**Scope:** DESIGN / CONTRACT-AMENDMENT only. No implementation code, no PRs, no SSOT edits." and "**Base:** … this doc modifies nothing there." — describes the envelope as originally authored against base `b0d78d86`. As of this PR that rc.20 amendment is **ratified and applied in-place (FORM A)** to the frozen SSOT; the design-time "no SSOT edits" wording is historical authoring context, not a live constraint on this ratified record. The Ratification lineage above is authoritative.

---

**Status:** v6 envelope (design / contract-amendment), FINAL. **v6 = v5 + N1/N2/F-NB4 non-blocking test/lint/cert hardening ONLY; NO design predicate/policy/grant/role/table change.** v5 CONVERGED — BOTH terminal re-gate-4 gates returned GO (Gate A-delta-4 `a4ce075a`; Gate B-delta-4 `a379e0de`), NO HALT; Gate B-delta-4 flagged 3 EXPLICITLY NON-BLOCKING hardening notes "for the trunk-commit record," and v6 folds exactly those 3 as additive test/lint/cert wording on an already-BOTH-GO design: **N1** (strengthen the `pg_policy.polpermissive` lint — group by effective role incl. `PUBLIC`/inheritance; reject an internally-disjunctive single `WITH CHECK`; behavioral positive-controls remain the PRIMARY proof), **N2** (state the option-(b) vacuous-deny guard invariant — ≥1 permissive policy per writable (rung, command)), and **F-NB4** (extend owner non-reachability to SET-ROLE assumability — conjoin the `MEMBER` variant of `pg_has_role`). No design predicate, policy, grant, role, or table is changed. v6 supersedes v5 (`a6e790fd`), which supersedes v4 (`a48ad69c`). Preserves EVERY verified v4 closure (all checks passed on v4 EXCEPT one bounded item) and closes the SINGLE remaining BLOCKING finding raised identically by BOTH re-gate-3 gates (Gate A-delta-3 `aa5cbf73` = CHANGES-NEEDED; Gate B-delta-3 `aa881074` = 1 blocking): the **RLS `WITH CHECK` composition semantics** — v4's construction is right but it justifies the composition with a FALSE PostgreSQL claim ("PostgreSQL requires ALL applicable `WITH CHECK` clauses to pass / they AND") and leaves the _realization_ unspecified, so an implementation could realize the status-pin, the workspace-bind, and the override as SEPARATE PERMISSIVE policies which combine with **OR** (not AND) → a foreign-workspace INSERT satisfying only the status-pin would be admitted (B2-INSERT / B-1 re-open). v5 (a) corrects the semantics, (b) **mandates** the composition be realized as a SINGLE compound `WITH CHECK` OR as `AS RESTRICTIVE` policies and **explicitly forbids** the multi-permissive-intended-to-AND realization, and (c) hardens the red-first negatives to an otherwise-valid row + adds a positive-control. It also folds Gate B-delta-3's NB-4-transitive nit (state owner non-reachability as TRANSITIVE membership). This is a PRECISE, LIGHT revision: every v4 closure (3-rung ladder / zero per-user; F1–F7; GA-1/3/4; B-1/B-2/B-3; B2-INSERT workspace bind itself; N-1..N-5; AD-1/AD-2; NB-1..NB-5; continuous -06 scan + L174 GUC fold; rc.20) carries forward intact. Prior rc.18/rc.19 evidence does NOT carry.
**Authoring authority:** Jason B1 ruling (2026-07-20T23:08Z) + Mos coordinator **OPTION A** (home the layer) + **Mos Q1 ruling (TIER-LEVEL)** + **Mos Q2 ruling (RLS `WITH CHECK` AUTHORIZED, two mandatory conditions)**. No new coordinator authority is required for v5: the composition fix is a DDL-realization detail + corrected PostgreSQL-semantics statement + test-wording hardening entirely inside the already-authorized `WITH CHECK`/`FORCE RLS` mechanism (Q2); it introduces no new principal, key, or authority axis. **Both delta-3 gates independently confirmed the per-user/same-tier boundary HOLDS** (the crit-1 defect is a TENANT-ISOLATION correctness risk, NOT a per-user authority axis).
**Base:** frozen SSOT at `b0d78d86`, `/src/mosaic-stack/docs/native-kanban-sot/` (READ-ONLY; this doc modifies nothing there).
**Scope:** DESIGN / CONTRACT-AMENDMENT only. No implementation code, no PRs, no SSOT edits.

**HALT self-check result (re-run for v5): NO HALT.** No v5 change forces two SAME-TIER writers to hold DIFFERENT WRITE AUTHORITY. The v5 composition fix pins **how** the already-uniform predicates are physically composed (one compound `WITH CHECK`, or `AS RESTRICTIVE`) — it changes no predicate's _content_ and adds no writer-varying axis; both delta-3 gates confirmed this is a tenant-isolation correctness pin, not a per-user distinction. The B2-INSERT fix ANDs a **shared, per-request workspace predicate** (`workspace_id = current_setting('mosaic.workspace_id', true)::uuid`) into every rung's INSERT `WITH CHECK` — applied **uniformly** to every writer in a tier, exactly like the B-2 read/`USING` predicate; it is tenant isolation, never a per-writer distinction. The B-1 sink-resident User-override remains keyed on **(workspace_id, task_id, tier)** — task-identity + tier ONLY, **NO per-federated-writer key** — so every writer inside a given tier is subject to the _identical_ veto for a given task. The five NB fixes (override-relation no-status enumeration; two claim-scopings; owner-toggle-FORCE containment naming; baseline runtime grants for the two capability roles) introduce **zero** per-writer authority. Per-writer _attribution_ remains an AUDIT concern routed to metadata (`task_events.actor_id`), never a DB credential/role/RLS key. The design remains satisfiable with the **fixed 3-rung role ladder** (User / Orchestrator / others), federated identity → rung at authorization time. The Q1 hard re-open trigger (same-tier / different write-authority) is **not** hit. See §5.

---

## 0. What the "raw task-status sink" is (grounding — unchanged from v1/v2)

- The canonical task-status store is **`tasks.status`** (SHARED-CONTRACT §5.4 L214 "canonical authority"); legacy **`mission_tasks.status`** is frozen read-only / prohibited as a write source (SHARED-CONTRACT §5.4 L219; §5.1 phase 1 L165). `tasks` is a **mutable** relation created by **KBN-100**. Canonical statuses are `backlog | ready | in_progress | blocked | in_review | done | cancelled` (SHARED-CONTRACT §3 L134); initial creation state is `backlog` (§5.4 L214 not-started→backlog).
- The append-only event relations `task_events, artifacts, task_checkpoints, task_checkpoint_artifacts, approval_decision_artifacts` receive runtime-only `SELECT, INSERT` with `UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER` **denied** (frozen §4 L178). That producer/consumer precedent — grants applied **after** KBN-100 creates the relations — is the mechanism this envelope extends to the mutable `tasks.status` sink and to the new sink-resident override table (§2.9).
- Today there is exactly one runtime login, `mosaic_runtime` (LOGIN INHERIT), sole member of NOLOGIN `mosaic_runtime_capability` (§4 L149-150). The sink therefore has **no writer-authority discrimination** — the root of RC19-B1-01.

The three B1 findings are writes to this sink; the two B2 findings are the privileged-fd → UID-drop handoff used by the runner/importer (§5 L184/L191). This envelope homes one coherent layer over both, now with the User-override and the SELECT/tenant predicate **resident at the sink**.

**[NB-2 / NB-3 — precise compromise-resistance scope (Mos Q1 accepted co-resident-pool residual; NO HALT).]** The prior "a compromised Gateway cannot bypass a User deny or read cross-workspace" framing is **overstated** and is corrected here. All three rung credentials are co-resident in one Gateway process (DB authenticates the _credential_, never the federated end-user — the accepted Mos Q1 residual), and the workspace GUC is _app-set_ with no per-tenant DB check. Precisely:

- **B-1 sink-enforces the User veto against the _Orchestrator-rung path_** — an Orchestrator-pool write to a task carrying an active User deny ERRORS in PostgreSQL regardless of app-layer behavior (a _buggy_ or Orchestrator-path-compromised Gateway cannot skip it). It does **NOT** stop a Gateway compromised badly enough to hold the **User** pool: User = god and may itself clear any veto (User-write-only on the override table). That is the accepted co-resident-pool residual, not a new hole.
- **B-2 + B2-INSERT sink-enforce tenant isolation against a _buggy_ Gateway** — an omitted/wrong workspace predicate fails **closed** (reads return zero rows; INSERTs ERROR on the NULL/mismatched GUC). They do **NOT** defend a _compromised_ Gateway that forges `mosaic.workspace_id` to a victim tenant, because the GUC carries no per-tenant DB authentication (accepted Mos Q1 residual). The genuine, real closure B2-INSERT delivers is the **buggy / unbound-INSERT** hole: without it, _any_ rung could write a foreign `workspace_id` on INSERT even with a correct GUC set — that is now impossible.

Defending against a fully compromised Gateway forging identity/tenant requires per-federated-user DB credentials = the HALT boundary; Mos Q1 explicitly accepts this residual and rules NO HALT. The claims in §2.9 (B-1) and §2.2/§2.4 (B-2/INSERT) are scoped to match.

---

## 1. Contract amendment (exact ownership + text changes)

### 1.1 Homing decision — one NEW owner card + minimal responsibility-widenings

The layer is genuinely **new scope**. The **minimal** closed/disjoint expansion adds **one new owner card, `KBN-101-10`**, owning two brand-new, currently-unowned globs (disjoint from every existing manifest → KBN-101-06 overlap/ownerless/path-existence still pass):

- `packages/db/src/sink-rbac/**` — B1 layer (policy artifact + schema + evaluator + ladder + connection-selection + status-UPSERT + invariant-set + view/rule-forbid enumeration).
- `packages/db/src/credential-handoff/**` — B2 library (SCM_RIGHTS + non-dumpable assert/verify).

Plus **responsibility-widenings of already-owned files** (no manifest-glob change → no overlap):

| Existing card                            | Already-owned path(s) touched                                                                             | Widened responsibility (v4; v3 items preserved)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| ---------------------------------------- | --------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `KBN-101-00`                             | `infra/pg-bootstrap/roles.sql`, `infra/pg-bootstrap/tests/**`                                             | **[GA-1 FIX]** Create the **fixed rung-ROLES** (3 LOGIN roles + their capability roles) with **deny-by-default base attributes** and **CONNECT** grants; bootstrap catalog tests that each rung role carries the safe attributes (F2) and is **non-owner** of the sink. **[AD-1 FIX]** Amend the frozen §4 **L176 CONNECT-allowlist certification** so the two new LOGIN rungs (`mosaic_runtime_user`, `mosaic_runtime_orchestrator`) are admitted to the `CONNECT` allowlist **and asserted `TEMPORARY`-denied**; otherwise the frozen L176 cert test REDS (it fails if an app login retains TEMPORARY, and it enumerates the CONNECT allowlist). **[NB-5 FIX]** Grant the two new capability roles (`mosaic_runtime_user_capability`, `mosaic_runtime_orchestrator_capability`) the **baseline frozen §4 L176 runtime grants** they need to function: `USAGE ON SCHEMA mosaic`, `USAGE ON SCHEMA drizzle` + `SELECT ON drizzle.__drizzle_migrations, drizzle.__mosaic_migration_manifest` (ledger read), and the relevant sequence `USAGE`/`SELECT` grants — mirroring what `mosaic_runtime_capability` already holds; without these the two new rungs cannot connect/operate and would FAIL the frozen §6 L222 runtime verify (missing inherited capability/sequence/ledger grants → fail-closed). **It owns NO DDL on `tasks` or the override table** — those relations do not exist at bootstrap time, so RLS/column-grant/policy/FORCE/unique-key/trigger DDL **cannot** live here.                                                                                                                                                                                                                                                                                                                 |
| `KBN-100` (producer; SPEC target of -10) | its own `packages/db/src/schema.ts` + generated `packages/db/drizzle/**` migration + migration tests      | **[GA-1 + GA-2/Q2 + B-1 + B-2 + B-3 + B2-INSERT FIX]** Homes ALL `tasks`-specific sink DDL **and the new `task_status_write_override` table DDL** **after** it creates `tasks`, per the frozen §4 L178 producer/consumer precedent: the rung column-grant matrix (F1/F7/N-3), the **RLS `WITH CHECK` write-source policies** (Q2/F1/N-3), **[B2-INSERT] the workspace-predicate `workspace_id = current_setting('mosaic.workspace_id', true)::uuid` as a conjunct of EVERY rung's INSERT enforced check on `tasks` — realized as a single compound `WITH CHECK` OR `AS RESTRICTIVE`, NEVER as separate permissive policies (v5 composition mandate, §1.4 item 3-bis) — (and thus into the UPSERT INSERT arm), and the symmetric INSERT workspace binding on `task_status_write_override`** so tenant isolation is homed at the sink on the write path too, the **per-rung `SELECT`/`UPDATE` `USING` tenant policies** (B-2), the **override-table subquery** in every `tasks` write policy (B-1), the `tasks (workspace_id,id)` **UNIQUE** candidate key (F4), the `actor_id` attribution metadata column (Q1 audit channel), the **no-status-normalizing-trigger / no-status-view / no-status-rule** invariants (F3/N-1/N-2) — **[NB-1] extended to cover the `task_status_write_override` relation as well** (no status-writing trigger/RULE/SECURITY DEFINER function on the override relation may write `tasks.status`), and — as the **TERMINAL migration step** — `ENABLE`/`FORCE ROW LEVEL SECURITY` on `tasks` and on the override table, run strictly **AFTER** all expand/backfill/repair DML (B-3). **KBN-100's DDL scope statement is explicitly amended** to include RLS + the override table on `tasks` under Mos Q2 coordinator co-authorization (§1.4). Certified deployed by KBN-101-09. |
| `KBN-101-01`                             | `packages/db/src/connection-identity.ts`(+spec), `apps/gateway/src/database/database.module.ts`(+spec)    | Provision **only the three generic rung pools** at boot; set the per-request **workspace session predicate** (B-2) on each checked-out connection. **[F2 FIX]** Extend the frozen L222 unsafe-attribute checkout assertion to **each** rung connection: effective role == authorized rung **AND** fail closed on SUPERUSER / CREATEROLE / CREATEDB / REPLICATION / **BYPASSRLS** / ownership of the sink tables (`DATABASE_ROLE_UNSAFE`). **[AD-2/N-5 FIX]** -01 **provisions pools only**; it does **not** import -10. The rung→pool SELECTION lives in -10's `connection-selection.ts`, which **consumes** -01's provisioned pools (import direction `10→01`; §2.2).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| `KBN-101-03`                             | `packages/db/src/migrator/**` (glob), **`docker/db-migrator.Dockerfile`**                                 | Consume -10's credential-handoff: **SCM_RIGHTS-only** fd acquisition + **non-dumpable re-verify** after the drop to `10003:10003`. **[GA-4(ii) FIX]** The root-only **migrator launch wrapper** homes here (the migrator image).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| `KBN-101-05`                             | `apps/gateway/Dockerfile`(+spec), renderer secret matrix                                                  | Renderer mounts **three** rung DSN secrets (`mosaic-db-runtime-url` + `mosaic-db-runtime-user-url` + `mosaic-db-runtime-orchestrator-url`), each `0600 10001:10001`, Gateway-only. Gateway rung-connection selection is a **DB-role choice, not a UID drop**, so -05 owns **no** SCM_RIGHTS/dumpable behavior (moved to -03 per GA-4(ii)).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| `KBN-101-02`                             | `packages/storage/src/{cli,migrate-tier}.ts`, `packages/storage/src/adapters/postgres.ts` (already-owned) | Importer privileged-fd case uses SCM_RIGHTS (extends existing safe-open, drop to `10002:10002`); status writes go through the -10 status-preserving-UPSERT helper.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| `KBN-101-06`                             | `tools/ci/fixtures/kbn101-ddl-inventory.json`, `.woodpecker/ci.yml`                                       | Add `KBN-101-10` to the inventory fixture/command matrix; add the rung-selection + SCM_RIGHTS + **per-tier RLS negatives** + **override-veto negative** + **cross-workspace read negative** + **[B2-INSERT] cross-workspace INSERT/UPSERT negative** + **NULL-GUC INSERT negative** + **owner/backfill-ordering** cases to the matrix. **[Gate A-delta-2 obs #2 / N-2 continuous — ADOPTED]** Home the **continuous no-status catalog scan as a -06 CI gate that runs on EVERY migration** (promoted from the v3 one-shot -09 recommendation): the scan asserts no status-writing trigger/RULE/`SECURITY DEFINER` function/view on `tasks` **or on `task_status_write_override`** (NB-1), so a future migration that adds a status-write path fails CI, not only the one-time cert.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |

### 1.2 §7 manifest expansion (KBN-101-06 must still pass)

Add exactly one row to the §7 card table (complete, disjoint ownership universe):

> | `KBN-101-10` declarative sink-RBAC + per-role connection-selection + credential-handoff | 00,01 | **Only:** `packages/db/src/sink-rbac/**`, `packages/db/src/credential-handoff/**`. It homes: the source-controlled declarative RBAC policy artifact + schema + evaluator; the fixed **rung ladder** + federation-aware identity→rung resolver; the rung→DB-credential **connection-selection** module (consumes -01 pools; import direction `10→01`); the **status-preserving-UPSERT** contract + **invariant field-set** module + **no-status view/rule/trigger enumeration**; and the **SCM_RIGHTS** credential-handoff + **non-dumpable** assert/verify library. It creates no roles, no DDL, no Compose/CI/deploy path; it is consumed by -00 (role names), -01 (connection wiring + identity/attribute verify), -02/-03/-05 (write path + fd handoff), specified-against by **KBN-100** (sink DDL: grants/RLS/`USING`+`WITH CHECK` policies/override-table/FORCE/unique-key/trigger-view-rule-invariant on `tasks`), and certified deployed by KBN-101-09. |

Amend the §7 L245 closing sentence (added clause **bold**): "The manifests above are the complete ownership universe for KBN-101 implementation paths **including KBN-101-10**; the KBN-101-06 inventory test fails on overlap, an ownerless in-scope path, or a nonexistent declared path."

**Dependency edges (v3, unchanged from v2 — acyclic; -10 depends only on 00,01):**

- `KBN-101-10 depends on 00,01`
- `KBN-101-02 depends on 01,03,10`
- `KBN-101-03 depends on 00,01,10`
- `KBN-101-05 depends on 00,03,10`
- `KBN-101-06 depends on 02,03,05,07,10`
- `KBN-101-08 depends on 00…07,10`
- `KBN-101-09 depends on KBN-100,08` (unchanged; evidence-only)

**Why still disjoint (KBN-101-06 green — UNCHANGED from v2):** the only NEW ownership is the two -10 globs. The B-1 override table, B-2 `USING` policies, and B-3 terminal-FORCE ordering are **all producer DDL homed in KBN-100's already-owned `schema.ts`/`drizzle/**`** (a *responsibility* widening on files KBN-100 already owns, exactly like the `tasks`sink DDL). The N-1/N-5 additions live inside -10's already-declared`sink-rbac/**`glob. AD-1 amends -00's already-owned`roles.sql`/tests. **No glob is split, narrowed, or shared → KBN-101-06 overlap/ownerless/path-existence stay green.\*\*

### 1.3 §4 identity-model amendment (per-role, closed additive set — F2 hardened; AD-1 CONNECT cert)

Add these rows to the §4 role table (§4 L141-151). **Per-ROLE, not per-user.** Implements Jason's B1 (User = god; main Orchestrator near-god, User-overridable; others deny-by-default):

| Role (added)                             | Attributes (F2-hardened)                                                                                                                                 | Membership / session use                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| ---------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `mosaic_runtime_user_capability`         | `NOLOGIN`, no ownership/admin attrs.                                                                                                                     | Holds the **User (god)** rung's named grants incl. `INSERT(status)`, `UPDATE(status)` + the status-transition RLS `WITH CHECK` policy on `tasks`; **plus the SOLE `INSERT/UPDATE/DELETE` grant on `task_status_write_override`** (B-1); never granted to Orchestrator/base.                                                                                                                                                                                                                                                       |
| `mosaic_runtime_orchestrator_capability` | `NOLOGIN`, no ownership/admin attrs.                                                                                                                     | Holds the **Orchestrator (near-god)** rung's grants; identical to User **except** (i) every `tasks` write policy **subqueries** the override table and is REJECTED at the sink when an active User deny row exists for that `(workspace_id, task_id, orchestrator)` (B-1); (ii) `INSERT(status)` is pinned by `WITH CHECK` to a **non-terminal initial status** (N-3) — only User may INSERT an arbitrary/terminal status; (iii) it has only `SELECT` (never write) on the override table. Scope is tier/task-identity only (F6). |
| `mosaic_runtime_user`                    | **`LOGIN INHERIT NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS`**, no ownership; **non-owner of every sink table + the override table**. | Member of `mosaic_runtime_user_capability` only (`WITH INHERIT TRUE, SET FALSE, ADMIN FALSE`); the connection-selection **User-rung** credential. **[AD-1]** Requires `CONNECT`, denied `TEMPORARY`.                                                                                                                                                                                                                                                                                                                              |
| `mosaic_runtime_orchestrator`            | **`LOGIN INHERIT NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS`**, no ownership; **non-owner of every sink table + the override table**. | Member of `mosaic_runtime_orchestrator_capability` only (same INHERIT/SET/ADMIN flags); the **Orchestrator-rung** credential. **[AD-1]** Requires `CONNECT`, denied `TEMPORARY`.                                                                                                                                                                                                                                                                                                                                                  |

The existing `mosaic_runtime` is confirmed already `LOGIN INHERIT` with no admin attrs (frozen L150) and non-owner; it becomes the **others / deny-by-default** base rung. On the sink it retains `SELECT` (workspace-scoped `USING`, B-2), `INSERT (explicit non-status column list)` (F1), and column-level `UPDATE` on **non-status, non-invariant, non-key, non-tenancy** columns only (F7), each `USING` workspace-scoped; it has **no** `INSERT(status)`, **no** `UPDATE(status)`, **no** `DELETE`, **no** `TRUNCATE` on `tasks`, **no** write on the override table, and RLS denies its status/override writes by default. The rung set is **fixed at three**.

**F2 note:** the three rung LOGIN roles' `NOBYPASSRLS` + `NOSUPERUSER` + **non-ownership** are load-bearing — `FORCE ROW LEVEL SECURITY` collapses for any SUPERUSER/BYPASSRLS role and RLS is silently bypassed by a table **owner**. These attributes are declared in -00 bootstrap, catalog-proven in -00 tests, and re-verified at every checkout by -01 (extended L222 assertion).

**[AD-1] CONNECT-allowlist certification amendment (frozen §4 L176):** L176 today grants `CONNECT` only to `mosaic_runtime`, `mosaic_migrator`, and the bootstrap actor, and its cert **fails if an unrelated login retains `CONNECT` or either application login retains `TEMPORARY`.** The two new LOGIN rungs are additional application logins that require `CONNECT` and must be `TEMPORARY`-denied. The -00 row + rc.20 text **explicitly amend the L176 allowlist** to `{mosaic_runtime, mosaic_runtime_user, mosaic_runtime_orchestrator, mosaic_migrator, bootstrap-actor}`, and the -00 cert asserts `TEMPORARY` denial for all three runtime rungs. Without this amendment the frozen -00 cert test REDS on the two new logins.

**rc.20 amendment text (v3 — extends v2)** — amend §4's closing note and SHARED-CONTRACT rc.5 L82/L88-90 ("Non-effect: role graph … unchanged / neither creates roles/secrets") with:

> **rc.20 (Envelope A) — authorized by Jason's declarative-RBAC B1 ruling + Mos OPTION A + Mos Q1 (TIER-LEVEL) + Mos Q2 (RLS):** adds (i) the fixed **User/Orchestrator/others** runtime rung-roles (per-ROLE, deny-by-default); each rung **LOGIN** role is `NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS`, **NON-OWNER** of every sink/override table, **added to the §4 L176 `CONNECT` allowlist**, and **asserted `TEMPORARY`-denied**. **No per-federated-user role or credential is created** — federated identity maps to a rung **at authorization time only**, and per-writer **attribution lives in metadata columns** (app-supplied `actor_id` on `task_events`), **never** in DB credentials/roles. (ii) Two new fixed rung DSN secrets **`mosaic-db-runtime-user-url`** and **`mosaic-db-runtime-orchestrator-url`** (Gateway-only, `0600 10001:10001`), extending the frozen runtime-URL secret row. (iii) **RLS `WITH CHECK` write-source policies (including the B2-INSERT per-rung INSERT tenant binding `workspace_id = current_setting('mosaic.workspace_id', true)::uuid`, composed as a SINGLE compound `WITH CHECK` or `AS RESTRICTIVE` — never multi-permissive-intended-to-AND, per the v5 composition mandate §1.4 item 3-bis) + per-rung `SELECT`/`UPDATE` `USING` tenant policies + `FORCE ROW LEVEL SECURITY`** on the sink table `tasks` **and on the new sink-resident `task_status_write_override` table** (tighten-only, deny-by-default) — a §10 schema-v1 **mechanism addition** beyond the prior grant/revoke-only model, authorized by Mos Q2 as coordinator co-authorization with Jason's B1. **The two new rung capability roles additionally receive the baseline frozen §4 L176 runtime grants (`USAGE ON mosaic`, `drizzle` ledger `SELECT`, sequence grants) [NB-5] so they satisfy the frozen §6 L222 runtime verify.** (iv) The **`task_status_write_override` table** (keyed `(workspace_id, task_id, tier)`, no per-writer key), written only by the User rung, read by the Orchestrator/base rung `tasks` write-policy subquery, homes the User-override **at the sink**. The sink DDL (grants + RLS `USING`/`WITH CHECK` + override table + FORCE + unique key + trigger/view/rule invariants) is homed in the **KBN-100 producer** after it creates `tasks`, with `FORCE RLS` as the **terminal** migration step after all backfill/repair DML, per the §4 L178 producer/consumer precedent.

> **Frozen-invariant note (authorization basis):** touching the frozen role graph, the §4 L176 CONNECT allowlist, and adding RLS + the override table are §10 contract-change classes (MISSION-MANIFEST §10; SHARED-CONTRACT L82/L88-90; frozen §4 L176). They are authorized here by **Jason B1 + Mos OPTION A + Mos Q1 + Mos Q2**. The addition is strictly a **fixed per-ROLE** set + a **tighten-only** RLS mechanism + a **task/tier-scoped** override table. It stops exactly at the HALT boundary: **no** per-federated-user topology is introduced (§5 proof).

### 1.4 §10 mechanism amendment — RLS `WITH CHECK` (write-source + INSERT tenant-bound) + `USING` + sink-resident override at the sink (Q2), with the two mandatory conditions

The frozen write-authority model is grant/revoke-only; **RLS appears nowhere in the frozen contract.** Mos Q2 **AUTHORIZES** adding declarative, deny-by-default, **enforce-AT-THE-SINK, fail-closed** RLS policies, because grant/revoke alone cannot express (a) row-level _write-source_ enforcement (pin new-row status, F1/N-3), (b) a _sink-enforced_ User-override that the Orchestrator-rung path cannot skip (B-1), (c) _tenant-scoped reads/updates_ (B-2), or (d) **[B2-INSERT] _tenant-scoped INSERTs_ — binding `workspace_id` on the write/create path**, which neither column grants nor the `USING` read policy can do (PostgreSQL does not apply `USING` to INSERT). RLS is **tighten-only**: it can only further restrict beyond the column grants, never widen them.

**KBN-100 producer DDL scope is explicitly amended** to include, on `tasks` (and, where noted, the override table):

1. `ALTER TABLE tasks ENABLE ROW LEVEL SECURITY;` — and the same on `task_status_write_override`.
2. **CONDITION (b) — EXPLICIT DECISION: `ALTER TABLE tasks FORCE ROW LEVEL SECURITY;`** (and on the override table) — DECIDED **YES/ON**, stated explicitly and not left defaulted, so that **even the table owner (`mosaic_schema_owner`) and any maintenance connection cannot silently bypass RLS**. (Directly closes the live U-Connect failure mode where an owner connection with `rls_forced=false` silently VOIDED RLS.)
3. A **deny-all default** posture (no permissive policy) plus per-rung policies:
   - **Write (`WITH CHECK`):** base/others rung → new-row `status = <initial state 'backlog'>` only, no status UPDATE; **Orchestrator rung → status INSERT pinned to a non-terminal initial status (N-3), and every write (`INSERT`/`UPDATE`/transition) additionally `WITH CHECK`'d against `NOT EXISTS(<active User deny row for (workspace_id, id, 'orchestrator')>)` (B-1)**; User rung → status INSERT (any legal status) / transition. Every write policy is `WITH CHECK` (write-source), tighten-only.
   - **[B2-INSERT — tenant isolation on the write path] Every rung's INSERT `WITH CHECK` on `tasks` MUST include the workspace predicate `workspace_id = current_setting('mosaic.workspace_id', true)::uuid` as a conjunct of the _same_ enforced check that carries the status-pin (and, for the Orchestrator rung, the B-1 override subquery) — see the COMPOSITION MANDATE (item 3-bis) for the exact realization.** This is REQUIRED because PostgreSQL does **NOT** apply `USING` to INSERT, and the explicit status-pinning `WITH CHECK` **suppresses** the `USING`→`WITH CHECK` substitution — so in v3 `workspace_id` was **unbound on the INSERT path** and any rung could `INSERT INTO tasks (workspace_id, …) VALUES (<foreign W2>, …)` (directly or via the sanctioned status-upsert INSERT arm) into a victim workspace, defeating B-2's "tenant isolation homed at the sink" goal and evading SHARED-CONTRACT §7.1 (body workspace forbidden). **CORRECTED SEMANTICS (v5 — the delta-3 fix):** multiple **PERMISSIVE** policies for the same command combine with **OR** — a row is admitted if it satisfies **ANY** one permissive policy's `WITH CHECK`, ANDed with all `AS RESTRICTIVE` policies' checks. "All applicable `WITH CHECK` clauses must pass / they AND" is **FALSE as a general rule** and is struck from this envelope; the AND-conjunction the B2-INSERT closure depends on holds ONLY (a) _within a single policy_ whose `WITH CHECK` is one AND-conjoined expression, or (b) _across `AS RESTRICTIVE` policies_. Realizing the status-pin, the workspace-bind, and the override as separate _permissive_ policies would let a foreign-workspace INSERT that satisfies only the status-pin be admitted by OR — re-opening B2-INSERT/B-1 — which item 3-bis forbids. **Fail-closed on NULL:** an absent GUC makes `current_setting(...,true)` return NULL, the equality yields NULL (not true), and — provided the predicate is a conjunct of the single enforced check (item 3-bis) — the INSERT **ERRORS at the sink**. The **same INSERT workspace binding is applied symmetrically to `task_status_write_override`**, under the identical composition mandate (its own single compound `WITH CHECK` or `AS RESTRICTIVE`).
   - **Read/lock (`USING`) — B-2:** per-rung `SELECT` and `UPDATE` `USING` policies **workspace-scoped** by the session predicate `workspace_id = current_setting('mosaic.workspace_id', true)::uuid` (set per request by -01, §2.2). **`USING(true)` is explicitly FORBIDDEN** — tenant isolation rides on this predicate; a lazy `USING(true)` would expose every workspace's rows to every rung and is a fail-closed contract violation caught by a negative test.
   - **3-bis. [v5 — LOAD-BEARING] COMPOSITION MANDATE (how the sink check MUST be realized; both delta-3 gates prescribed it).** Per rung, per command (INSERT / UPDATE / transition), the sink enforcement of the status-pin **AND** the workspace-bind **AND** (Orchestrator rung only) the User-override subquery MUST be realized as EITHER:
     - **(a) a SINGLE policy** whose `WITH CHECK` is the _full conjunction_ — `<status-pin> AND workspace_id = current_setting('mosaic.workspace_id', true)::uuid` and, for the Orchestrator rung, `AND NOT EXISTS(<active User-override deny row for (workspace_id, id, 'orchestrator')>)`; **OR**
     - **(b)** the status-pin as the **SOLE PERMISSIVE** policy for that command, **plus** the workspace-bind and (Orchestrator) the override subquery authored **`AS RESTRICTIVE`** (restrictive policies AND with everything, so a row must pass every restrictive check _and_ at least one permissive check).
     - **EXPLICITLY FORBIDDEN:** realizing the status-pin, the workspace-bind, and the override as **multiple _permissive_ policies whose predicates are intended to AND.** Permissive policies combine with **OR**, so that realization admits a foreign-workspace INSERT that satisfies only the status-pin (cross-tenant injection) and equally bypasses the B-1 override — exactly the delta-3 defect. This mandate applies to the `tasks` INSERT/UPDATE/transition policies **AND** to the `task_status_write_override` table's own policies (same single-compound-`WITH CHECK`-or-`AS RESTRICTIVE` requirement; never multi-permissive-intended-to-AND). The producer DDL and the -09/-06 certification assert the realized policies are either single-compound or `AS RESTRICTIVE` (never separate permissive policies expected to AND) — a lint/catalog check over `pg_policy.polpermissive` backs it.
     - **[v6 — N1: strengthened `pg_policy.polpermissive` lint (supplementary, NOT sufficient).]** The `pg_policy.polpermissive` lint (continuous -06 scan, §2.7) MUST (a) count permissive policies **grouped by EFFECTIVE role — including `PUBLIC` and role inheritance**, not merely by the policy's named `TO` role: a `TO PUBLIC` (or inherited-through-a-capability-role) permissive policy applicable to a rung's command is counted **alongside** that rung's status-pin, because at evaluation time it OR-widens exactly like a second same-role permissive policy — so a `TO PUBLIC` permissive next to a rung's status-pin is a **lint failure**; and (b) ideally **reject an internally-disjunctive single `WITH CHECK`** — a single policy whose expression is itself `status_pin OR workspace_bind` satisfies the naive one-permissive-policy count yet violates the composition mandate exactly as two permissive policies would, so the lint should detect a top-level `OR` between the status-pin and the workspace-bind/override conjuncts within one policy expression. **The lint is SUPPLEMENTARY, not sufficient:** the **behavioral positive-controls remain the PRIMARY proof** of correct composition (dropping the workspace conjunct — resp. the override subquery — alone flips the hardened negative to a PASS; §2.4 clause 5 / §2.9). The lint backstops the catalog shape; it does not replace the behavioral proof.
     - **[v6 — N2: option-(b) vacuous-deny guard invariant — ≥1 permissive per writable (rung, command).]** Under option (b) (status-pin as the **sole PERMISSIVE** policy + workspace-bind/override `AS RESTRICTIVE`), PostgreSQL admits a row only if **≥1 PERMISSIVE `WITH CHECK` is TRUE AND all RESTRICTIVE checks pass** — so if a writable (rung, command) has **zero** permissive policies, every restrictive-only evaluation denies and the command **over-denies / fails closed** (nothing can ever be written). Therefore there **MUST be ≥1 PERMISSIVE policy per writable (rung, command)** — this "≥1 permissive per writable (rung, command)" is the **load-bearing option-(b) guard invariant** (the workspace-bind/override being restrictive is safe _only_ because the status-pin supplies the required permissive). It is verified by the mandated **"same-workspace valid-status write succeeds" positive tests** for each writable command — INSERT, transition/UPDATE, and SELECT — which would FAIL (spurious over-deny) if the permissive were dropped, and by the N1 lint confirming exactly one permissive status-pin (grouped by effective role) is present per writable (rung, command).
4. **B-3 migration ordering (TERMINAL FORCE):** all expand/backfill/repair DML on `tasks` (SHARED-CONTRACT §5.1 phase-3 L165-171, §5.3 L188) runs **FIRST**, while `tasks` has RLS **disabled**; the `ENABLE`/`FORCE ROW LEVEL SECURITY` statements are the **TERMINAL** DDL of the activation migration. **No standing `mosaic_schema_owner` ALLOW write policy exists after activation** (that would recreate the unconstrained owner write path = U-Connect mode). Any schema_owner maintenance policy, if ever needed, is **migration-only** and must be proven **unreachable by the 3 runtime LOGIN roles** + a negative test.

**CONDITION (a):** every runtime per-role LOGIN role (`mosaic_runtime`, `mosaic_runtime_user`, `mosaic_runtime_orchestrator`) **MUST remain NON-OWNER** of every sink table **and the override table** (owner stays `mosaic_schema_owner`). Enforced by -00 bootstrap catalog assertion + re-verified at each checkout by -01 (F2). A rung role that owns a sink/override table is a fail-closed contract violation.

**Break-glass boundary (B-3, named explicitly in KBN-101-09 cert):** the ONLY identities that legitimately bypass `FORCE RLS` are the sanctioned break-glass actors named in the frozen contract — `mosaic_extension_owner` (`NOLOGIN SUPERUSER`, §4.1 L146) and the external platform bootstrap actor (superuser, §4/§7; §9 L266 residual authority). Both are `NOLOGIN`/external, carry no runtime credential, and are outside application containment. The -09 cert **names these two as the accepted, audited boundary** — not a new hole — and asserts the three runtime LOGIN rungs are NOT superuser/NOT BYPASSRLS and cannot assume either.

**[NB-4 — owner-toggle-FORCE containment is NON-REACHABILITY, not incapability.]** The -09 break-glass enumeration must **additionally name `mosaic_schema_owner`** (frozen §4 L145, `NOLOGIN NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS`) as a **contained-but-CAPABLE** path. A table **owner** — regardless of `NOSUPERUSER`/`NOBYPASSRLS` — can `ALTER TABLE tasks DISABLE ROW LEVEL SECURITY` or `ALTER TABLE tasks NO FORCE ROW LEVEL SECURITY` and then write freely; `FORCE`/`NOBYPASSRLS` do **not** make an owner incapable. So the containment claim is **NOT** "the owner cannot bypass RLS" — it is **"the owner role is NOT REACHABLE from the three runtime LOGIN rungs."** The -09 cert asserts this non-reachability **explicitly**: (i) `mosaic_schema_owner` is `NOLOGIN` (no direct credential); (ii) it is reachable only via `mosaic_migrator`'s `SET ROLE` (frozen §4 L147, migrator runner-before-Gateway, `max:1` locked migration session), which is **not** one of the three runtime rungs and holds no runtime pool; (iii) none of `mosaic_runtime` / `mosaic_runtime_user` / `mosaic_runtime_orchestrator` is a member of, or can `SET ROLE` to, `mosaic_schema_owner` or `mosaic_migrator` (catalog-proven at -00, re-verified at every checkout by -01's L222 non-owner/assumability assertion). **[NB-4-transitive — Gate B-delta-3 nit, folded]** the non-reachability assertion in the -09 cert MUST be stated as **TRANSITIVE membership**, not merely the absence of a **direct** `pg_auth_members` row: PostgreSQL's ownership/privilege check returns true for an **inherited** membership reached _through a capability role_, which would confer the owner's `ALTER TABLE … NO FORCE` / `DISABLE ROW LEVEL SECURITY` right. The assertion therefore uses the recursive predicates — `NOT pg_has_role('mosaic_runtime_user', 'mosaic_schema_owner', 'USAGE')` (and the same for each runtime rung against `mosaic_schema_owner` and `mosaic_migrator`), equivalently `NOT has_privs_of_role(<rung>, 'mosaic_schema_owner')` — which fold in transitive/inherited membership through any intermediate (capability) role. The frozen §6 L222 fail-closed-on "owner/migrator identity **or assumability**" check plausibly already covers this transitive case; v5 states "**transitive membership**" **explicitly** in the -09 cert assertion so no implementation reads "non-member" as only the direct-edge check. **[v6 — F-NB4: cover SET-ROLE assumability, not only inherited privilege.]** The v5 predicates `NOT pg_has_role(<rung>, 'mosaic_schema_owner', 'USAGE')` / `NOT has_privs_of_role(<rung>, 'mosaic_schema_owner')` capture the **inherited-privilege** axis, but a membership granted `WITH INHERIT FALSE, SET TRUE` yields `has_privs_of_role = FALSE` **yet still allows `SET ROLE mosaic_schema_owner`** followed by `ALTER TABLE … NO FORCE ROW LEVEL SECURITY` — an assumability path the `USAGE`/`has_privs_of_role` predicate alone does **not** close. The -09 cert assertion therefore **conjoins the `MEMBER` variant** — `NOT pg_has_role(<rung>, 'mosaic_schema_owner', 'MEMBER')` **AND** `NOT pg_has_role(<rung>, 'mosaic_migrator', 'MEMBER')` — for **each of the three runtime rungs** (`mosaic_runtime`, `mosaic_runtime_user`, `mosaic_runtime_orchestrator`); the `MEMBER` privilege captures SET-ROLE reachability **regardless of `INHERIT`**, so `pg_has_role(rung, owner, 'USAGE')` **AND** `pg_has_role(rung, owner, 'MEMBER')` are asserted false together. This is stated explicitly rather than leaning on "frozen §6 L222 assumability plausibly covers it." (The intended role graph is already safe — per envelope §1.3 + frozen §4 L150, each rung is a member of **only** its own capability role, `WITH INHERIT TRUE, SET FALSE, ADMIN FALSE`, and of no owner/migrator role — so no live `SET TRUE` edge to the owner/migrator exists; this fold is **assertion-completeness hardening, not a live hole.**) The owner's toggle-then-write capability is therefore real but confined to the migrator/owner phase (frozen §5, runner-before-Gateway), never to a live runtime rung — that is the containment, stated as **transitive non-reachability** rather than incapability.

**Red-team requirement (baked into §3/§4; v5-HARDENED so the negatives cannot false-green under the OR-trap):** each per-rung policy is proven **deny-by-default via NEGATIVE tests PER TIER** in real PostgreSQL:

- an unauthorized write-source (base terminal-status INSERT/transition) that **ERRORS**;
- **[B2-INSERT — hardened] a cross-workspace INSERT/UPSERT using a row OTHERWISE VALID for the rung** — a status the rung's pin **ACCEPTS** (e.g. **base rung + `status='backlog'`**, and no active override), differing from a passing insert ONLY in `workspace_id = <foreign W2>` — so the rejection **isolates the workspace bind** (not a status/override rejection). Tested both directly and via the status-upsert INSERT arm; it **ERRORS at the sink**. **Positive-control:** removing the workspace-bind conjunct **alone** (leaving the status-pin) flips this negative to a **PASS**, proving the _workspace bind_, not the status-pin, is doing the rejecting (and proving the composition is a single enforced conjunction / RESTRICTIVE, not an OR of separate permissive policies).
- **[B-1 — hardened] an Orchestrator write vetoed by an active User-override deny row, using a transition the Orchestrator pin OTHERWISE ACCEPTS** (a legal non-terminal transition on `(W, T)` that would succeed absent the deny row) — so the rejection **isolates the override subquery**. It **ERRORS at the sink**. **Positive-control:** removing the override subquery **alone** flips this negative to a **PASS**, proving the _override_, not the status-pin/workspace-bind, is doing the rejecting.
- a **cross-workspace `SELECT` under the wrong/absent session predicate** → zero rows;
- **[B2-INSERT] a NULL-GUC INSERT** (absent `mosaic.workspace_id`) that **ERRORS** (fail-closed on NULL);
- a **same-workspace INSERT with a valid status** that **succeeds** (proving the predicate composes with F1/N-3 and does not over-deny);
- an **owner/maintenance connection attempting a post-activation `tasks` write** that must **fail under `FORCE`**.
  All rejections **ERROR at the sink**. The two positive-controls are load-bearing: they are the direct proof that the composition is single-compound-`WITH CHECK`-or-`AS RESTRICTIVE` (delta-3), because under the forbidden multi-permissive-OR realization the hardened cross-workspace / override negatives would already PASS (false-green) without removing anything.

---

## 2. Design

### 2.1 Declarative RBAC policy (source-controlled artifact + schema)

- **Artifact:** `packages/db/src/sink-rbac/policy.task-status.v1.ts` — a source-controlled, versioned, deny-by-default policy object; the single source of truth for "who may write the sink." No policy lives in the database except the _derived_ GRANT/RLS state the KBN-100 producer emits from it.
- **Schema:** `packages/db/src/sink-rbac/policy.schema.ts` — a typed schema (zod/TS) validating: `rungs` (exactly the fixed ladder), per-rung `allow`/`deny` verbs (`insert`, `insert:status`, `update:<column-set>`, `transition:status`, `delete` — always deny), `federationMap` (federated-identity-claim → **rung**, never a role/credential per user), and `userOverride`.
  - **[F6 FIX] `userOverride` scope guardrail:** the schema **constrains** override predicates to **tier- + task-identity (row) scope `(workspace_id, task_id, tier)`** and **explicitly FORBIDS** a per-federated-writer identity as an override or authority key (the Q1 re-open trigger). A policy that names a per-federated-writer identity as an override/authority key **fails schema validation** (fail-closed at load). The override is realized as the sink-resident `task_status_write_override` table (§2.9), NOT as app-resolved state. Per-writer attribution is not an authority input; it flows only to the audit metadata column (§2.6).
- **Evaluator:** `packages/db/src/sink-rbac/evaluate.ts` — pure `(identityClaims, requestedWrite) → Decision ∈ {allow(rung), deny(reason)}`, **deny-by-default**, tier resolution only. It **only chooses a rung**; it never mints credentials and — critically (B-1) — **it is NOT the enforcement point for the User-override**: the override is enforced in PostgreSQL by the write-policy subquery, so a compromised Gateway that skips the evaluator still cannot bypass a User deny.
- **Ladder / federation-awareness:** `packages/db/src/sink-rbac/ladder.ts` — fixed order `User > Orchestrator > others` and `resolveRung(federatedIdentity) → rung` at authorization time (Q1: federation-awareness lives in the resolver; the sink authorizes by the writer's declared ROLE/tier).
- **Enforcement is AT THE SINK, fail-closed:** the evaluator's rung choice only selects _which pre-provisioned connection_ is used; PostgreSQL then enforces via (a) revoked base privileges, (b) column-level `INSERT(status)`/`UPDATE(status)` granted only to the User/Orchestrator capabilities, (c) `FORCE ROW LEVEL SECURITY` + deny-all default + per-rung `WITH CHECK` policies **including the override subquery** (B-1), (d) per-rung `SELECT`/`UPDATE` `USING` **workspace predicate** (B-2, tenant isolation at the sink), (e) `DELETE/TRUNCATE` revoked from all runtime rungs, and (f) `UPDATE` on key/tenancy/invariant columns revoked from **all** rungs (F7). A mis-authorized OR override-vetoed OR cross-workspace write **fails closed in PostgreSQL** because the connection's effective DB role lacks the privilege or the policy predicate rejects the row — caller discipline is not trusted.

### 2.2 Per-role credential + connection-selection model (NO per-user roles; import direction pinned)

```
federated writer ──(verified identity claim)──► evaluate.ts ──► rung (one of 3, fixed)
                                                                 │
                                      connection-selection.ts ───┤ selects the PRE-PROVISIONED
                                        (in -10; consumes -01)    │ pool for that rung; sets
                                                                 │ SET LOCAL mosaic.workspace_id
                                                                 ▼
                    mosaic_runtime_user | mosaic_runtime_orchestrator | mosaic_runtime
                     └── PostgreSQL enforces grants + FORCE RLS WITH CHECK(+override) + USING(workspace) ──┘
```

- **`packages/db/src/sink-rbac/connection-selection.ts`** maps `rung → pooled connection`. **Exactly three** connection pools, one per rung, each opened with that rung's **fixed** mounted-secret DSN. Credentials = rungs = **3**, constant.
- **[AD-2/N-5 — import direction pinned]** `-01` (`database.module.ts`) **provisions ONLY the three generic rung pools** at boot and knows nothing of rung _selection_. The rung→pool SELECTION lives entirely in **-10's `connection-selection.ts`**, which is **consumed by the write-path cards (`-02`/`-03`/`-05`, which already `depends on 10`)** and is **NEVER imported by `-01`**. Direction is therefore `10 → 01` (10's selection consumes 01's pools) — **acyclic; there is no `01 → 10` cycle.** An impl lane must not read "01 wires 10" as `01 → 10`.
- **[B-2 — workspace session predicate]** on checkout, before the first query, -01 sets `SET LOCAL mosaic.workspace_id = <verified request workspace>` inside the request transaction; the per-rung `USING` policies **and the B2-INSERT `WITH CHECK`** read `current_setting('mosaic.workspace_id', true)::uuid`. The predicate is set from the **server-verified** tenant context, never from a body field (SHARED-CONTRACT §7.1 "Body workspace fields are forbidden"). A missing/invalid setting → `USING` yields no rows (fail-closed read) and INSERT `WITH CHECK` yields NULL→ERROR (fail-closed write), never cross-workspace exposure.
  - **[NB-3 — compromise scope]** the GUC is **app-set with no per-tenant DB authentication**, so B-2 (reads/UPDATE `USING`) and B2-INSERT protect a **buggy** Gateway (omitted/wrong predicate → fail-closed), NOT a **compromised** Gateway that forges `mosaic.workspace_id` to a victim tenant (accepted Mos Q1 co-resident-pool residual; defending it requires per-user DB creds = the HALT boundary). The genuine closure B2-INSERT delivers is the **buggy / unbound-INSERT** hole: even with a correct GUC, v3 left `workspace_id` unbound on INSERT so any rung could stamp a foreign workspace — now impossible.
  - **[Gate B 2(a) — poisoned-pool / SET LOCAL negative]** the `mosaic.workspace_id` GUC is folded into the frozen L174 **poisoned-pooled-session-reset + transaction `SET LOCAL` restoration** negative test (which already covers `search_path`): a negative proves `mosaic.workspace_id` is **transaction-scoped via `SET LOCAL`** (mirroring the frozen `SET LOCAL search_path` discipline, §4 L152) so a pooled connection **cannot leak a stale workspace** across requests — an un-reset/poisoned session fails closed, and a committed/rolled-back transaction does not carry the prior request's workspace.
- **[F2 FIX] Identity + attribute verification at checkout** (`connection-identity.ts`): verify effective role == the rung's expected DB role **AND** assert the safe attributes — fail closed (`DATABASE_ROLE_UNSAFE`) on SUPERUSER, CREATEROLE, CREATEDB, REPLICATION, **BYPASSRLS**, or ownership of any sink/override table. Extends the frozen L222 check to **each** rung connection.
- **No per-federated-user role/credential:** a new federated user needs **zero** new DB roles/credentials/secrets/pools — it resolves to an existing rung. Federation growth is O(1) in DB-role count.

### 2.3 Status-preserving UPSERT on a stable natural key (F4 bound)

- **`packages/db/src/sink-rbac/status-upsert.ts`** — the single sanctioned refresh helper: `INSERT INTO tasks (natural_key…, <mutable non-status cols…>) VALUES (…) ON CONFLICT (<natural key>) DO UPDATE SET <mutable non-status cols…>` — **`status` is never in the `DO UPDATE SET` list**, so a refresh preserves existing `status` byte-for-byte.
- **[B-2 dependency]** the `ON CONFLICT` conflict-probe/refresh reads the existing row; under `FORCE RLS` this requires the per-rung `SELECT`/`UPDATE` `USING` policy to admit the row (workspace-scoped). Without B-2's `USING` policies the probe would see zero rows and the UPSERT would spuriously INSERT-conflict or mis-refresh — B-2 is what makes the sanctioned UPSERT actually work post-activation.
- **[B2-INSERT dependency]** the UPSERT's **INSERT arm** is a `tasks` INSERT and is therefore subject to the B2-INSERT workspace `WITH CHECK` (§1.4/§2.4): a status-upsert that supplies a foreign `workspace_id` (or runs under an absent GUC) **ERRORS at the sink**, closing the sanctioned-UPSERT INSERT path that v3 left tenant-unbound. The helper sets `workspace_id` from the server-verified tenant context (never a body field, §7.1); it matches the session GUC by construction.
- **[F4 FIX] Natural key:** the tenant-scoped stable identity **`(workspace_id, id)`**. No frozen `tasks(workspace_id,id)` unique key exists (only `missions_workspace_id_uidx`, rc.4 L94) — `ON CONFLICT` against a nonexistent unique index is a **HARD planning error** that fails loud. Therefore **KBN-100 MUST create `tasks (workspace_id,id)` UNIQUE** (aligned to the SI-001 pattern, SHARED-CONTRACT §5.2). **Fallback:** if KBN-100 keys `tasks` on global `id` only, the UPSERT natural key **re-binds to `(id)`** (spec-level, no HALT).
- **Status changes only via an authorized transition:** `transitionStatus()` guarded by (a) the rung's `transition:status` policy verb, (b) `UPDATE(status)` present only on User/Orchestrator capabilities, (c) the RLS `WITH CHECK` transition policy (admits the update only as an explicit transition, never as a refresh/grant side effect) **plus the override subquery for the Orchestrator rung (B-1)**, and (d) the `USING` workspace predicate to see/lock the row (B-2). `DELETE` is denied to all runtime rungs → **DELETE + default-INSERT status reset is impossible at the sink** (fails closed on the DELETE).

### 2.4 INSERT-time status constraint (F1 BLOCKING + N-3 hardening)

Base `mosaic_runtime` must not stamp an arbitrary terminal status at creation, **and the Orchestrator rung must not create a task directly at a terminal status** (N-3). Layered fail-closed controls (homed in the KBN-100 producer DDL):

1. **Column-privilege:** `GRANT INSERT (<explicit non-status column list>) ON tasks TO mosaic_runtime_capability;` — the base rung **cannot name `status` on INSERT**, so `status` takes its column **DEFAULT** (`backlog`). `INSERT(status)` is granted **only** to the User/Orchestrator capabilities.
2. **RLS `INSERT … WITH CHECK` (base):** pins **new-row `status = 'backlog'`** for the base rung.
3. **[N-3 FIX] RLS `INSERT … WITH CHECK` (Orchestrator):** pins the Orchestrator rung's new-row status to a **non-terminal initial status** (`status IN {backlog, ready}`; never `done`/`cancelled`/`in_review`). **Only the User (god) rung may INSERT an arbitrary/terminal status.** This prevents an Orchestrator creating a task directly at `done`/`cancelled`, skipping the transition/lease/review trail (SHARED-CONTRACT §7.2 `POST /tasks` L272 vs `POST /tasks/:taskId/transition` L275). The exact terminal/non-terminal set is bound by KBN-100 to the §3 L134 vocabulary.
4. **[B2-INSERT FIX] RLS `INSERT … WITH CHECK` (EVERY rung, tenant binding):** every rung's INSERT sink-check MUST include `workspace_id = current_setting('mosaic.workspace_id', true)::uuid` as a conjunct of the **same enforced check** that carries the status-pin (base=`backlog`, Orch=non-terminal, User=any) **and** the B-1 override subquery on the Orchestrator rung. `status` is bound by clause 2/3; `workspace_id` is bound by this conjunct; they are orthogonal columns so there is no conflict. **[v5 — corrected PostgreSQL semantics; the delta-3 fix]** the earlier justification "because PostgreSQL requires all applicable `WITH CHECK` clauses to pass, they AND" is **FALSE and is struck**: multiple **PERMISSIVE** policies for a command combine with **OR** (a row is admitted if it satisfies **ANY** one permissive `WITH CHECK`, ANDed with all `AS RESTRICTIVE` checks). The AND this closure needs holds ONLY (a) within a _single_ policy whose `WITH CHECK` is one AND-conjoined expression, or (b) across `AS RESTRICTIVE` policies. **Fail-closed on NULL:** an absent GUC → NULL equality → INSERT ERRORS — _provided_ the workspace conjunct sits in the single enforced check (clause 5). This closes the v3 gap where the explicit status `WITH CHECK` suppressed the `USING`→`WITH CHECK` substitution, leaving `workspace_id` unbound on INSERT and allowing any rung to INSERT into a foreign workspace.
5. **[v5 COMPOSITION MANDATE — LOAD-BEARING] Single-compound-`WITH CHECK`-or-`AS RESTRICTIVE`, never multi-permissive-intended-to-AND.** The status-pin (clause 2/3), the workspace-bind (clause 4), and (Orchestrator) the B-1 override subquery MUST be realized per rung, per command as EITHER **(a)** a **SINGLE policy** whose `WITH CHECK` is the full conjunction `<status-pin> AND workspace_id = current_setting('mosaic.workspace_id', true)::uuid [AND NOT EXISTS(<active override deny row>)]`; **OR (b)** the status-pin as the **sole PERMISSIVE** policy **plus** the workspace-bind and (Orchestrator) the override authored **`AS RESTRICTIVE`**. Realizing them as **multiple _permissive_ policies intended to AND is EXPLICITLY FORBIDDEN** — permissive policies OR, so a foreign-workspace INSERT satisfying only the status-pin (e.g. base + `backlog` + foreign `workspace_id`) would be OR-admitted, re-opening B2-INSERT, and an override-vetoed Orchestrator write satisfying the status-pin would likewise slip the B-1 veto. The **identical mandate applies to `task_status_write_override`'s own policies** (single compound `WITH CHECK` or `AS RESTRICTIVE`; never multi-permissive-AND). A `pg_policy.polpermissive` catalog check + the hardened positive-control negatives (below) prove the realization. **[v6 — N1]** the `pg_policy.polpermissive` check is strengthened to count permissive policies **grouped by EFFECTIVE role (including `PUBLIC` and role inheritance)** — a `TO PUBLIC`/inherited permissive applicable to a rung's command counts alongside its status-pin — and to **reject an internally-disjunctive single `WITH CHECK`** (a lone policy whose expression is `status_pin OR workspace_bind` OR-widens exactly like two permissive policies); the lint is **supplementary, and the behavioral positive-controls below remain the PRIMARY proof** (§1.4 item 3-bis). **[v6 — N2]** because option (b) admits a row only when **≥1 permissive `WITH CHECK` is TRUE AND all restrictive checks pass**, there **MUST be ≥1 PERMISSIVE policy per writable (rung, command)** — the load-bearing option-(b) vacuous-deny guard — else the command over-denies (fails closed); this invariant is proven by the mandated "same-workspace valid-status write succeeds" positive tests (INSERT, transition/UPDATE, SELECT).

**Red-first tests (v5-hardened):** base-rung `INSERT … status='done'` **ERRORS** (column-privilege and/or RLS); base-rung INSERT omitting status succeeds at DEFAULT; **Orchestrator `INSERT … status='done'` ERRORS (N-3)**, Orchestrator `INSERT … status='backlog'` succeeds; User-rung `INSERT … status='done'` succeeds. **[B2-INSERT — hardened valid-status form]** the cross-workspace negative uses a row **otherwise valid for the rung** — **base rung + `status='backlog'` + `workspace_id=<foreign W2>`, no active override** — differing from a passing insert ONLY in `workspace_id`, so the **ERROR** isolates the _workspace bind_ (not a status/override rejection); tested direct and via the status-upsert INSERT arm. **Positive-control:** removing the workspace-bind conjunct **alone** flips this to a **PASS** (proving the bind — not the status-pin — rejects, hence a single enforced conjunction / RESTRICTIVE, not a permissive OR). An INSERT under an absent `mosaic.workspace_id` GUC **ERRORS** (fail-closed on NULL); a same-workspace INSERT with a valid status **succeeds** (predicate composes with F1/N-3, does not over-deny).

### 2.5 Invariant / key / tenancy field-set (F7 — closure)

- **`packages/db/src/sink-rbac/invariant-set.ts`** defines the invariant field-set = every sink column NOT in the explicitly-mutable set: `{ natural-key columns (workspace_id, id), status, creation/tenancy columns, immutable metadata }`. The complement (title, tags-normalized, due_at, rank, …) is the mutable set the UPSERT `DO UPDATE` touches.
- **[F7 FIX] `UPDATE` on key/tenancy/invariant columns (`workspace_id`, `id`, tenancy columns) is REVOKED from ALL rungs — including User and Orchestrator.** A re-key would otherwise **launder status** (relocate a row into a new identity to escape the status invariant). Column-level `UPDATE` grants for every rung exclude these columns.
- **Grant/data-plane disjointness (RC19-B1-03):** grants are declarative + physically separate from the data plane, so a grant/policy mutation writes **zero** `tasks` rows. A test applies an arbitrary policy/grant delta → asserts **zero byte delta** on any `tasks` row (closes RC19-B1-03 by construction).

### 2.6 Per-writer attribution → metadata column (Q1 audit channel)

- Per-writer attribution (which federated writer inside a tier acted) is an **AUDIT** concern, not an authority concern. It is captured as an **app-supplied `actor_id` metadata column on `task_events`** (append-only, already runtime `INSERT/SELECT`-only per frozen §4 L178). KBN-100 owns the column; the application supplies the verified federated-writer identity as **data**.
- It is **never** a DB credential, role, or RLS predicate key, and (per F6) never a `userOverride`/authority key (the override is keyed on task+tier, not writer). This keeps "which writer acted" auditable **without** a per-writer DB topology — i.e. without hitting the Q1 HALT trigger.

### 2.7 No-status-write via trigger / view / rule (F3 BLOCKING + N-1 + N-2)

Column-level `UPDATE(status)` alone does not close every indirect status-write path. Three complementary invariants (homed in KBN-100 producer; enumerated by -10's `invariant-set.ts`/no-status enumeration; certified deployed by KBN-101-09):

- **F3 — no status-normalizing trigger on `tasks`:** no trigger on `tasks` writes/normalizes `status` outside the sanctioned `transitionStatus()` path. The transition path is the **only** status writer.
- **[N-2 FIX + NB-1 + continuous-scan ADOPTED] Complete no-status-write enumeration (F3 completeness):** the cert asserts, in addition to F3: **no AFTER trigger** on `tasks` executing `UPDATE tasks SET status`; **no `SECURITY DEFINER` function** that writes `tasks.status` (frozen §4 L176 already forbids `SECURITY DEFINER` unless a separately reviewed exception — cited as the backstop); **no trigger on a RELATED runtime-writable table** (`task_events` and the other §4 L178 relations) that writes `tasks.status`; and **no `CREATE RULE`** on `tasks`. **[NB-1]** The enumeration is **extended to the `task_status_write_override` relation**: no status-writing trigger / RULE / `SECURITY DEFINER` function on the override relation may write `tasks.status` (the override table is runtime-writable by the User rung, so it is exactly the class §2.7's related-table clause must cover). The enumeration **scans function BODIES** (`pg_proc.prosrc` / dependency graph) for `tasks.status` writes, not merely `pg_trigger` rows. **[Gate A-delta-2 obs #2 — ADOPTED, not just recommended]** this enumeration is now a **continuous -06 CI catalog scan run on EVERY migration** (promoted from the v3 one-shot -09 recommendation), so a _later_ migration that adds a status-writing trigger/function/rule/view on `tasks` **or** on `task_status_write_override` **fails CI**, not only the one-time -09 cert. The -09 deployed cert still records the final deployed proof; the -06 scan is the standing gate. **[v6 — N1]** the same continuous -06 scan family carries the **strengthened `pg_policy.polpermissive` composition lint** (§1.4 item 3-bis / §2.4 clause 5): on every migration it counts permissive policies **grouped by effective role — including `PUBLIC` and role inheritance** (a `TO PUBLIC`/inherited permissive applicable to a writable command counts alongside that rung's status-pin) and flags an **internally-disjunctive single `WITH CHECK`** (`status_pin OR workspace_bind` within one policy). This lint is **supplementary**: it backstops the catalog shape but is **not sufficient** — the behavioral positive-controls (§2.4 clause 5 / §2.9) remain the PRIMARY proof that the composition is single-compound/`AS RESTRICTIVE` rather than an OR of permissive policies.
- **[N-1 FIX] no status-write via VIEW or RULE:** forbid any `VIEW` or `RULE` on `tasks` that yields a status-write path. An owner-owned view runs with the owner's privileges (`security_invoker = false` by default), side-stepping rung grants; an `ON INSERT/UPDATE DO INSTEAD` rule rewrites a write onto `tasks` similarly. The `invariant-set.ts` enumeration **forbids such views/rules OR mandates `security_invoker = true` + ZERO runtime grants** on any view over `tasks`. A negative test proves a rung cannot mutate `tasks.status` through any view/rule.

### 2.8 B2 — SCM_RIGHTS credential-acquisition + non-dumpable re-verify (F5 hardened — unchanged from v2)

- **`packages/db/src/credential-handoff/scm-rights.ts`** — the privileged process (the **-03 migrator launch wrapper**) opens the privileged fd (attestation signing key, §5 L191) **before** the UID drop and passes the **descriptor itself** over a Unix-domain socket via an `SCM_RIGHTS` ancillary message. The receiver **never** re-opens `/proc/self/fd/N` (the kernel re-checks permission and returns EACCES after the drop — the FD5 failure). `O_CLOEXEC` managed explicitly on both ends.
  - **[F5 FIX] Socket authentication:** the transfer socket **MUST** be a `socketpair()` created **pre-fork** (no filesystem socket) **OR** a filesystem socket in a `0700` directory verified with **`SO_PEERCRED`** (assert peer UID/GID/PID). The receiver sets **`MSG_CMSG_CLOEXEC`** on `recvmsg`. An unauthenticated/anonymous peer is rejected fail-closed.
- **`packages/db/src/credential-handoff/process-hardening.ts`** — after **every** credential/UID transition, re-assert `prctl(PR_SET_DUMPABLE, 0)` and **verify** `prctl(PR_GET_DUMPABLE) == 0`; treat `dumpable != 0` as a fail-closed abort.
- **Consumers:** KBN-101-03 migrator wrapper (drop to `10003:10003`), KBN-101-02 importer (privileged-fd case, drop to `10002:10002`). The runtime rung-connection selection is a **DB-role choice, NOT an OS-UID transition** — no new setuid surface, no dumpability handling, reinforcing the no-per-user / no-new-privilege-drop property.

### 2.9 [B-1 FIX] Sink-resident, task/tier-scoped User-override table (the User deny is now enforced IN PostgreSQL)

**Problem (Gate B-delta B-1):** in v2 the evaluator resolved the User-override in-app _before_ selecting a connection, so a compromised/buggy Gateway on the Orchestrator pool could bypass a User deny — contradicting v2 §1.4/Q2, which mandates that "an Orchestrator write vetoed by a User-override deny must ERROR at the sink." App-resolution is not sink-enforcement.

**Fix (option a — DB-resident override, RLS-forced):**

- **New relation `mosaic.task_status_write_override`** (owned/created by the KBN-100 producer, exactly like `tasks`), columns: `workspace_id`, `task_id`, `tier` (enum `{orchestrator}` for v1 — the only vetoable sub-god tier; extensible to a future 4th rung), `active boolean`, `created_by_actor_id` (audit metadata, NOT an authority key), timestamps. **Primary/unique key `(workspace_id, task_id, tier)`** — **task-identity + tier ONLY; NO per-federated-writer column is part of the key or an authority input** (preserves F6 + the Q1 HALT boundary: every Orchestrator-tier writer is vetoed identically for a given task).
- **Who may WRITE it (sink-enforced):** `INSERT/UPDATE/DELETE` on the override table is granted **ONLY** to `mosaic_runtime_user_capability` (the User god rung), with the table under `FORCE RLS` and a `WITH CHECK` policy binding the row's `workspace_id` to the session workspace predicate. **[B2-INSERT parity]** that `WITH CHECK` workspace binding applies to the override table's **INSERT** path too (`workspace_id = current_setting('mosaic.workspace_id', true)::uuid`, fail-closed on NULL), so the override table's write path carries the identical symmetric tenant isolation as `tasks` — a User-rung INSERT of a veto row for a foreign workspace, or under an absent GUC, **ERRORS at the sink**. **[v5 COMPOSITION MANDATE parity]** the override table's write policies are subject to the SAME composition rule as `tasks` (§1.4 item 3-bis / §2.4 clause 5): the workspace-bind (and any status/authority conjunct) MUST be realized as a **single compound `WITH CHECK`** OR **`AS RESTRICTIVE`** — **never as multiple _permissive_ policies intended to AND** (which would OR-admit a foreign-workspace veto row). The Orchestrator and base rungs have **no** write privilege — a non-User attempt to author/clear a veto **ERRORS at the sink**. Thus only the User rung can raise or lift a veto.
- **Who READS it:** all three rung capabilities get **`SELECT`** on the override table (workspace-scoped `USING`), because the `tasks` write policy subquery evaluates as the current (querying) rung role. The read is confined to the querying connection's workspace by the override table's own `USING` predicate.
- **How it vetoes (the subquery):** every `tasks` **write policy** for the **Orchestrator rung** (`INSERT … WITH CHECK`, `UPDATE … WITH CHECK`, and the transition `WITH CHECK`) is extended with:

  ```sql
  AND NOT EXISTS (
    SELECT 1 FROM mosaic.task_status_write_override o
    WHERE o.workspace_id = tasks.workspace_id
      AND o.task_id      = tasks.id
      AND o.tier         = 'orchestrator'
      AND o.active
  )
  ```

  So an Orchestrator-tier write to a task carrying an active User deny is **REJECTED in PostgreSQL**, regardless of app-layer behavior. **[v5 COMPOSITION MANDATE]** this `NOT EXISTS(<override>)` subquery MUST be a **conjunct of the Orchestrator rung's single compound `WITH CHECK`** (alongside the status-pin and the workspace-bind), OR authored **`AS RESTRICTIVE`** — it may **NOT** be a separate _permissive_ policy intended to AND, because permissive policies OR and an Orchestrator write satisfying the status-pin permissive policy would then be OR-admitted despite an active deny (bypassing B-1). The User rung's own `tasks` policies do **not** subquery the override (User = god; the User authored the deny and overrides it). The base rung already cannot write status.

- **Per-tier NEGATIVE test (real PostgreSQL, red-first; v5-HARDENED):** insert an active override row for `(W, T, orchestrator)` via the User rung; then an Orchestrator-rung write on `(W, T)` **using a transition the Orchestrator pin OTHERWISE ACCEPTS** (a legal non-terminal `UPDATE`/transition that would succeed absent the deny row, and under the correct workspace GUC) **must ERROR at the sink** — so the rejection **isolates the override subquery** (not a status/workspace rejection). **Positive-control:** removing the override subquery **alone** flips this negative to a **PASS**, proving the _override_ — not the status-pin or workspace-bind — is doing the rejecting (and proving the subquery is a single-enforced conjunct / RESTRICTIVE, not an OR of separate permissive policies). Clearing the row (`active=false`, User rung only) re-permits the Orchestrator write; a non-User attempt to write the override table **ERRORS**. This proves the User-override is **sink-enforced** (satisfies v2 Q2) and stays within Mos Q1 tier-level (task/tier-scoped, not per-writer).

**[NB-2 — compromise-resistance scope of B-1.]** B-1 sink-enforces the veto against the **Orchestrator-rung path** — an Orchestrator-pool write to a vetoed task ERRORS in PostgreSQL regardless of app behavior. It does **NOT** claim to stop a Gateway compromised badly enough to hold the **User** pool: User = god and holds the sole write on the override table, so a compromised-User-pool Gateway can itself clear the veto. That is the **accepted co-resident-pool residual** (Mos Q1, NO HALT), not a defended boundary. The v3 §0 framing "a compromised Gateway cannot bypass a User deny" is corrected to "an Orchestrator-**path** write cannot bypass a User deny at the sink." Defending against a compromised User-pool Gateway would require per-federated-user DB credentials = the HALT boundary, which Mos Q1 explicitly declines.

**HALT note:** because the key is `(workspace_id, task_id, tier)` and never `writer`, this fix does **not** give two same-tier writers different authority — it gives the _whole_ Orchestrator tier the _same_ per-task veto. The B2-INSERT workspace predicate is likewise applied uniformly to every writer in a tier. NO HALT.

---

## 3. Findings-closure map (each → fail-closed, red-first testable)

| Finding                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | Closure                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Fail-closed enforcement point                                                                                                                                                                                                      | Test (red-first, real PostgreSQL / real UID drop)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **RC19-B1-01** raw sink has no enforceable authority boundary                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Declarative deny-by-default RBAC (§2.1) → fixed rung → per-rung DB credential; PG enforces via revoked base privileges + `FORCE RLS` deny-all + per-rung `WITH CHECK`.                                                                                                                                                                                                                                                                                                                                                       | At the sink: effective DB role lacks the privilege; mis-authorized write errors in PG.                                                                                                                                             | -00: rung roles created, safe attrs, non-owner. KBN-100: base `UPDATE(status)`/`DELETE` denied, User/Orch allowed. -01: checkout identity==rung + safe-attr.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| **RC19-B1-02** DELETE+default-INSERT resets status                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Status-preserving UPSERT on `(workspace_id,id)`; `status` excluded from `DO UPDATE`; `DELETE` revoked all rungs; status only via authorized transition.                                                                                                                                                                                                                                                                                                                                                                      | At the sink: DELETE fails closed; refresh cannot touch `status`.                                                                                                                                                                   | KBN-100 + -09: refresh preserves `status` byte-stable; DELETE denied; transition-only status change.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| **RC19-B1-03** grant change breaks non-status compatibility                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | Invariant field-set (§2.5); grants declarative + physically separate → grant mutation writes zero `tasks` rows.                                                                                                                                                                                                                                                                                                                                                                                                              | Structural: data plane and grant plane disjoint.                                                                                                                                                                                   | Apply arbitrary policy/grant delta → **zero byte delta** on all `tasks` rows + invariant-set membership test.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **RC19-B2-01** FD5 `/proc/self/fd` EACCES after UID drop                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | SCM_RIGHTS descriptor-passing (§2.8); never re-open `/proc/self/fd/N` post-drop; explicit `O_CLOEXEC`; authenticated socket (F5).                                                                                                                                                                                                                                                                                                                                                                                            | Post-drop process receives a live fd; no privileged re-open.                                                                                                                                                                       | Drop UID → `/proc/self/fd` re-open EACCES/absent vs SCM_RIGHTS receive succeeds; unauthenticated peer rejected.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| **RC19-B2-02** dumpability resets after credential transition                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Re-assert + **verify** `PR_SET_DUMPABLE=0` after every transition; fail closed if `PR_GET_DUMPABLE != 0`.                                                                                                                                                                                                                                                                                                                                                                                                                    | Process aborts if dumpable ≠ 0 post-transition.                                                                                                                                                                                    | After simulated setuid: assert `PR_GET_DUMPABLE == 0`; inject reset → fail-closed abort.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| **F1 (BLOCKING)** INSERT-time status unconstrained for base rung                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | `GRANT INSERT (non-status list)` → status DEFAULT for base; RLS `INSERT … WITH CHECK` pins new-row status to initial; `INSERT(status)` only User/Orch (§2.4).                                                                                                                                                                                                                                                                                                                                                                | At the sink: base status-on-insert denied by column-privilege and/or RLS `WITH CHECK`.                                                                                                                                             | **Red-first:** base `INSERT … status='done'` ERRORS; base INSERT omitting status → DEFAULT; User/Orch initial-status INSERT succeeds.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| **F2 (BLOCKING)** rung LOGIN roles lack declared/verified safe attributes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | Declare both rung roles `NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS` + non-owner (§1.3); extend L222 checkout assertion (§2.2).                                                                                                                                                                                                                                                                                                                                                                           | Bootstrap catalog + every checkout: fail closed on SUPERUSER/BYPASSRLS/ownership.                                                                                                                                                  | -00 catalog asserts attrs + non-ownership; -01 injects unsafe attr/ownership → `DATABASE_ROLE_UNSAFE`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| **F3 (BLOCKING)** BEFORE-trigger status bypass                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Invariant: no trigger on `tasks` writes/normalizes `status` outside `transitionStatus()` (§2.7); homed in KBN-100 producer.                                                                                                                                                                                                                                                                                                                                                                                                  | Producer DDL admits no status-normalizing trigger; transition path is only status writer.                                                                                                                                          | KBN-100 static: enumerate triggers on `tasks`, none assign status. **-09 deployed:** base UPDATE of a permitted col cannot change status via any trigger.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| **F4 (non-blocking)** no frozen `tasks(workspace_id,id)` unique key                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Bind `tasks (workspace_id,id)` UNIQUE as explicit KBN-100 req; else re-bind UPSERT to `(id)` (§2.3).                                                                                                                                                                                                                                                                                                                                                                                                                         | `ON CONFLICT` resolves to a real unique index; else hard planning error (fails loud).                                                                                                                                              | KBN-100 migration: unique key exists; UPSERT plans/executes; missing-key variant fails loud.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| **F5 (non-blocking)** SCM_RIGHTS socket unauthenticated                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | `socketpair()` pre-fork **or** `SO_PEERCRED` + `0700` dir; `MSG_CMSG_CLOEXEC` on `recvmsg` (§2.8).                                                                                                                                                                                                                                                                                                                                                                                                                           | Fd transfer only over an authenticated peer; received fd close-on-exec.                                                                                                                                                            | Unauthenticated/wrong-peer rejected; `SO_PEERCRED` mismatch fails closed; `MSG_CMSG_CLOEXEC` asserted.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| **F6 (non-blocking)** `userOverride` scope                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Schema constrains override to `(workspace_id,task_id,tier)`; **forbids** per-writer key (§2.1); realized as the sink-resident override table (§2.9). Attribution → metadata (§2.6).                                                                                                                                                                                                                                                                                                                                          | Fail-closed at policy load: a per-writer authority key **fails schema validation**.                                                                                                                                                | Schema test: per-writer override/authority key **rejected**; tier/task-scoped accepted.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| **F7 (non-blocking)** re-key launders status                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Revoke `UPDATE(workspace_id,id,tenancy)` from **all** rungs incl. User/Orch (§2.5).                                                                                                                                                                                                                                                                                                                                                                                                                                          | At the sink: no rung may UPDATE key/tenancy columns.                                                                                                                                                                               | Each rung (incl. User) `UPDATE workspace_id`/`id` **ERRORS**.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **B-1 (BLOCKING; composition PINNED in v5)** User-override was app-enforced, not sink-enforced                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Sink-resident `task_status_write_override` table `(workspace_id,task_id,tier)`, User-rung-write-only; the `NOT EXISTS(<active deny>)` subquery is a **conjunct of the Orchestrator rung's single compound `WITH CHECK`** (or authored **`AS RESTRICTIVE`**), **never a separate permissive policy** — else an Orchestrator write satisfying the status-pin permissive policy is OR-admitted despite the deny (§2.9 / §1.4 item 3-bis).                                                                                       | At the sink: an active User deny → Orchestrator write REJECTED in PG (single enforced check, not OR-bypassable); non-User cannot author the veto.                                                                                  | **Per-tier NEGATIVE (real PG; v5-hardened):** User inserts deny row → Orchestrator write **using a transition the pin OTHERWISE ACCEPTS** **ERRORS** (isolates the override). **Positive-control:** dropping the override subquery alone flips it to PASS (proves single-conjunction/RESTRICTIVE, not permissive-OR). Clear row → re-permitted; Orch/base write to override table **ERRORS**.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **B-2 (BLOCKING)** FORCE + `WITH CHECK`-only bricks all reads (SELECT returns 0 rows for every rung and owner)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Add per-rung `SELECT`/`UPDATE` `USING` policies, **workspace-scoped** via `current_setting('mosaic.workspace_id')`; forbid `USING(true)` (§1.4/§2.2). Homes tenant isolation at the sink.                                                                                                                                                                                                                                                                                                                                    | At the sink: reads succeed only for the session's workspace; wrong/absent predicate → zero rows (no cross-tenant leak).                                                                                                            | Post-activation: each rung `SELECT`/UPSERT-probe within its workspace **succeeds**; a `SELECT` under a foreign/absent `mosaic.workspace_id` returns **zero** rows; a `USING(true)` variant **fails the isolation negative**.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| **B-3 (BLOCKING)** owner/backfill write path under FORCE RLS                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Backfill/repair DML runs FIRST (RLS disabled); `ENABLE`/`FORCE RLS` is the **TERMINAL** migration step; **no standing schema_owner ALLOW write policy** after activation; break-glass (`mosaic_extension_owner` §4.1 L146 + external bootstrap actor §9 L266) named in -09 cert (§1.4).                                                                                                                                                                                                                                      | Migration ordering: backfill completes before FORCE binds; post-activation owner write has no policy → fails closed.                                                                                                               | KBN-100 migration test: backfill INSERTs succeed pre-FORCE; **post-activation `mosaic_schema_owner` `tasks` write ERRORS under FORCE**; no runtime rung is superuser/BYPASSRLS; -09 names the two break-glass actors as the accepted boundary.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| **N-1 (non-blocking)** VIEW/RULE status-write path                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | Forbid views/rules on `tasks` yielding a status write, OR mandate `security_invoker=true` + zero runtime grants; enumerated by `invariant-set.ts` (§2.7).                                                                                                                                                                                                                                                                                                                                                                    | Enumeration admits no status-writable view/rule; any view over `tasks` is invoker-rights + ungranted.                                                                                                                              | Negative: a rung cannot mutate `tasks.status` through any view/rule; enumeration fails an owner-rights view with runtime grants.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| **N-2 (non-blocking)** F3 enumeration incomplete                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | Extend enumeration: no AFTER trigger `UPDATE tasks SET status`; no `SECURITY DEFINER` fn writing `tasks.status` (L176 backstop); no trigger on related runtime-writable table (`task_events`, L178) writing `tasks.status`; no `CREATE RULE`; scan function **BODIES** (§2.7). One-shot -09 cert; recommend continuous -06 CI scan.                                                                                                                                                                                          | Producer/-09 cert admits no indirect status-write path.                                                                                                                                                                            | Catalog scan of `pg_proc.prosrc`/triggers/rules asserts none write `tasks.status`; deployed behavioral proof; (recommended) -06 CI re-scan per migration.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| **N-3 (non-blocking)** Orchestrator can INSERT terminal status                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | Orchestrator `INSERT(status)` `WITH CHECK` pinned to non-terminal initial status; only User may INSERT arbitrary/terminal (§2.4).                                                                                                                                                                                                                                                                                                                                                                                            | At the sink: Orchestrator terminal-status INSERT rejected by `WITH CHECK`.                                                                                                                                                         | Orch `INSERT … status='done'` **ERRORS**; Orch `status='backlog'` succeeds; User `status='done'` succeeds.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| **N-4 (non-blocking)** transition-graph legality not DB-enforced (`done→backlog` reset by another name)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | **DECISION (documented, §2.10):** edge-legality is **app-enforced** within near-god/god authority; the sink closes RC19-B1-02 **for base only** (DELETE-denial + no base status write). No status-writing trigger is added (would collide with F3/N-2); a validation-only guard is deferred.                                                                                                                                                                                                                                 | Documented boundary: User/Orch hold near-god/god authority; illegal edges are an app-layer concern, not a sink guarantee.                                                                                                          | -09 records the decision + asserts base cannot reset status at the sink; app-layer transition-graph tests are owned by the Gateway command lane (out of KBN-101 scope).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| **N-5 / AD-2 (non-blocking)** import direction ambiguity                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | `-01` provisions generic pools only; rung→pool SELECTION lives in `-10`'s `connection-selection.ts`, consumed by `-02/-03/-05`; **never imported by `-01`** → `10→01`, acyclic (§2.2).                                                                                                                                                                                                                                                                                                                                       | Structural: no `01→10` edge exists.                                                                                                                                                                                                | Static import test: `-01` has no import of `sink-rbac/connection-selection`; `-02/-03/-05` do; graph acyclic.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **AD-1 (completeness)** frozen §4 L176 CONNECT cert reds on the 2 new logins                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Amend the L176 allowlist to admit `mosaic_runtime_user`/`mosaic_runtime_orchestrator` + assert their `TEMPORARY` denial; named in -00 row/rc.20 (§1.3).                                                                                                                                                                                                                                                                                                                                                                      | -00 cert: CONNECT allowlist includes the 2 new logins; all 3 runtime rungs `TEMPORARY`-denied.                                                                                                                                     | -00 cert asserts CONNECT granted to the 2 new logins and no runtime rung retains `TEMPORARY`; an un-amended allowlist REDS.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| **B2-INSERT (BLOCKING; composition PINNED in v5)** tenant isolation not enforced on the INSERT write path (v3 bound workspace only in `SELECT`/`UPDATE` `USING`; PostgreSQL does not apply `USING` to INSERT, and the explicit status `WITH CHECK` suppresses `USING` substitution → `workspace_id` unbound on INSERT → any rung can INSERT/UPSERT into a foreign workspace). **[v5 delta-3]** the v4 justification ("all `WITH CHECK` AND") was FALSE — multiple permissive policies OR — so the workspace conjunct must be pinned into a _single compound check or `AS RESTRICTIVE`_, else the bind is bypassable. | Include `workspace_id = current_setting('mosaic.workspace_id', true)::uuid` as a **conjunct of the single compound INSERT `WITH CHECK`** (with the F1/N-3 status-pin and, Orchestrator, the B-1 override subquery) **OR** author it **`AS RESTRICTIVE`**, on `tasks` (and the UPSERT INSERT arm) + symmetric on `task_status_write_override`. **Multiple _permissive_ policies intended to AND are EXPLICITLY FORBIDDEN** (they OR). Corrected semantics + realization mandate in §1.4 item 3-bis / §2.4 clauses 4–5 / §2.9. | At the sink: an INSERT/UPSERT with a foreign `workspace_id` fails the single enforced check; a NULL GUC → NULL predicate → INSERT ERRORS (fail-closed). Write-side tenant isolation homed at the sink and no longer OR-bypassable. | **Red-first (real PG; v5-hardened):** the cross-workspace negative uses an **otherwise-valid row** (base + `status='backlog'` + no override, differing only in `workspace_id=<foreign W2>`) so the **ERROR** isolates the workspace bind; direct and via status-upsert INSERT arm. **Positive-control:** dropping the workspace conjunct alone flips it to PASS (proves single-conjunction/RESTRICTIVE, not permissive-OR). NULL-`mosaic.workspace_id` INSERT **ERRORS**; same-workspace valid-status INSERT **succeeds** (no over-deny); override-table foreign-workspace INSERT **ERRORS**.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **NB-1 (non-blocking)** override relation absent from the no-status enumeration                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Extend the F3/N-1/N-2 no-status-write enumeration **and the -09 cert / continuous -06 scan** to `task_status_write_override`: no status-writing trigger / RULE / `SECURITY DEFINER` function on the override relation writes `tasks.status` (§2.7).                                                                                                                                                                                                                                                                          | Enumeration/CI admits no indirect status-write path via the override relation.                                                                                                                                                     | Catalog + fn-body scan asserts no trigger/rule/SECURITY-DEFINER on `task_status_write_override` writes `tasks.status`; a planted one REDS the -06 scan.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| **NB-2 (non-blocking)** overstated B-1 compromise claim                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | Scope §0/§2.9 wording: B-1 sink-enforces the veto against the **Orchestrator-rung path**; a compromised **User**-pool Gateway (User=god) can clear a veto — accepted Mos Q1 co-resident residual, NO HALT (§0/§2.9).                                                                                                                                                                                                                                                                                                         | Documented boundary: sink-enforcement is Orchestrator-path-scoped; the User-pool residual is accepted, not defended.                                                                                                               | Doc/claim assertion in -09 cert notes: the override-veto negative proves the **Orchestrator-path** ERROR; the framing no longer claims User-pool compromise resistance.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| **NB-3 (non-blocking)** overstated B-2 compromise claim                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | Scope §0/§2.2 wording: the workspace GUC is app-set with no per-tenant DB check → B-2 + B2-INSERT protect a **buggy** Gateway (omitted predicate → fail-closed), NOT a **compromised** one forging the GUC (accepted residual). The B2-INSERT unbound-INSERT closure remains a real fail-closed win (§0/§2.2).                                                                                                                                                                                                               | Documented boundary: fail-closed on omission/NULL; forged-GUC cross-tenant is the accepted per-user residual.                                                                                                                      | Cross-workspace read → zero rows; NULL/foreign-GUC INSERT ERRORS (buggy-Gateway closure proven); doc states forged-GUC is out of scope (HALT boundary).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| **NB-4 (non-blocking; v5 states transitive)** owner-toggle-FORCE containment mis-stated as incapability                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | Name `mosaic_schema_owner` (reachable via `mosaic_migrator` `SET ROLE`) in the -09 break-glass enum as **contained-but-CAPABLE**: an owner can `ALTER TABLE tasks DISABLE/NO FORCE RLS` then write regardless of NOSUPERUSER/NOBYPASSRLS → containment = **transitive non-reachability from the 3 runtime LOGIN rungs**, asserted explicitly (§1.4).                                                                                                                                                                         | -09 cert: owner toggle-then-write is real but confined to the migrator/owner phase; runtime rungs cannot reach `mosaic_schema_owner`/`mosaic_migrator` through any inherited (capability-role) path.                               | **[NB-4-transitive]** -09 asserts non-reachability as **TRANSITIVE membership** — `NOT pg_has_role(<rung>, 'mosaic_schema_owner', 'USAGE')` / `NOT has_privs_of_role(...)` recursion, NOT merely the absence of a direct `pg_auth_members` row (ownership check returns true for an _inherited_ membership through a capability role). Frozen §6 L222 "assumability" plausibly already covers this; "transitive membership" is stated explicitly. **[v6 — F-NB4]** the assertion additionally **conjoins the `MEMBER` variant** — `NOT pg_has_role(<rung>, 'mosaic_schema_owner', 'MEMBER')` **AND** `NOT pg_has_role(<rung>, 'mosaic_migrator', 'MEMBER')` for each of the 3 runtime rungs — because a `WITH INHERIT FALSE, SET TRUE` membership yields `has_privs_of_role = FALSE` yet still permits `SET ROLE … ; ALTER TABLE … NO FORCE`; the `MEMBER` privilege captures SET-ROLE reachability regardless of `INHERIT` (the intended graph has each rung `SET FALSE` to only its capability role, so this is assertion-completeness, not a live hole). `mosaic_schema_owner` is `NOLOGIN`, reachable only via `mosaic_migrator` `SET ROLE`; the 3 runtime rungs are transitive non-members and non-assumers (catalog + L222 checkout). |
| **NB-5 (non-blocking)** 2 new capability roles lack baseline runtime grants → fail frozen §6 L222 verify                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | Grant `mosaic_runtime_user_capability` / `mosaic_runtime_orchestrator_capability` the frozen §4 L176 baseline runtime grants (`USAGE ON SCHEMA mosaic`; `USAGE ON SCHEMA drizzle` + `SELECT` on the two ledger relations; relevant sequence `USAGE`/`SELECT`) at -00 (§1.1/§1.3).                                                                                                                                                                                                                                            | Bootstrap: the 2 new rungs hold the baseline grants → they connect/operate and pass the L222 runtime verify.                                                                                                                       | -00 catalog asserts each new capability role holds `USAGE ON mosaic`, ledger `SELECT`, sequence grants; an omission → L222 runtime verify fails closed (missing inherited grant).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| **Q2 per-tier deny-by-default (red-team requirement; v5 composition-pinned)**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | Per-rung **single compound `WITH CHECK`** (status-pin + B2-INSERT workspace bind + Orchestrator override) **or `AS RESTRICTIVE`** — **never multi-permissive-intended-to-AND** — plus `USING` + `FORCE RLS`; deny-all default (§1.4 item 3-bis).                                                                                                                                                                                                                                                                             | At the sink, every tier: unauthorized write-source rejected even for owner/maintenance (`FORCE`); tenant/override binds not OR-bypassable.                                                                                         | **NEGATIVE per tier (v5-hardened):** base terminal-status INSERT/transition ERROR; **Orchestrator write under User-override deny, using an otherwise-accepted transition, ERROR (+ positive-control: drop override subquery → PASS)**; **cross-workspace INSERT/UPSERT with an otherwise-valid status ERROR (+ positive-control: drop workspace conjunct → PASS)**; NULL-GUC INSERT ERROR; owner/maintenance post-activation write ERROR (`FORCE` proven); cross-workspace read → zero rows; **same-workspace valid-status write SUCCEEDS per writable command (INSERT, transition/UPDATE, SELECT) — the [v6 — N2] ≥1-permissive-per-writable(rung,command) option-(b) vacuous-deny guard**; `pg_policy.polpermissive` check confirms single-compound-or-RESTRICTIVE, **[v6 — N1] grouped by effective role incl. `PUBLIC`/inheritance and rejecting an internally-disjunctive single `WITH CHECK` — supplementary to, never a substitute for, the behavioral positive-controls (PRIMARY proof)**.                                                                                                                                                                                                                                          |

---

## 4. Implementation card DAG (owner + disjoint manifest, red-first at Gate A/B)

```
contract(amended) ─► KBN-101-00 (rung-ROLES + capability roles, safe attrs [F2],
                     │            deny-default base, CONNECT + [AD-1] L176 allowlist
                     │            amend (2 new logins CONNECT, TEMPORARY-denied);
                     │            bootstrap catalog tests. NO tasks/override DDL [GA-1])
                     │
        KBN-101-01 ──┤ (provisions 3 generic rung pools; sets mosaic.workspace_id
                     │  session predicate [B-2]; checkout identity==rung AND
                     │  safe-attribute/non-owner verify [F2, extended L222].
                     │  Does NOT import -10 [AD-2/N-5])
                     │
        KBN-101-10 ──┘ depends 00,01:
                        packages/db/src/sink-rbac/**  (policy+schema[F6]+evaluator+ladder+
                                                       connection-selection[consumes 01; 10→01, N-5]+
                                                       status-upsert[F4]+invariant-set[F7]+
                                                       no-status trigger/view/rule enum[N-1,N-2])
                        packages/db/src/credential-handoff/** (scm-rights[F5] + process-hardening +specs)
                              │
      ┌─────────────┬────────┼──────────────────────┬──────────────────────────────┐
 KBN-101-03     KBN-101-05  KBN-101-02          KBN-100 (producer lane)          KBN-101-09 (evidence-only)
 (dep 00,01,10) (dep 00,03, (dep 01,03,10)      SPEC target of -10:              (dep KBN-100,08)
 migrator        10)         importer fd +       homes tasks + override DDL       DEPLOYED cert:
 wrapper:        renderer:   sink adapter uses    AFTER create:                   real rung INSERT/
 SCM_RIGHTS      3 rung DSN   status-upsert       - rung column-grant matrix       transition success;
 SEND + dumpable secret       (drop 10002)         [F1,F7,N-3]                     override-veto [B-1];
 re-assert       mounts;                          - RLS WITH CHECK(+override)      cross-workspace read
 (drop 10003)    Gateway                           + USING workspace pred          zero-rows [B-2];
 [GA-4(ii):      Dockerfile;                       [Q2,B-1,B-2, conds a&b]         backfill-then-FORCE
 docker/db-      NO SCM_RIGHTS                     - task_status_write_override     ordering + owner-write
 migrator.       (DB-role, no                       table [B-1]                    denial [B-3] + break-
 Dockerfile]     UID drop)                         - tasks(workspace_id,id) UNIQUE  glass named;
                              │                     [F4]                            base status
                        KBN-101-06 (dep 02,03,05,07,10): inventory += KBN-101-10;   INSERT/UPDATE/DELETE
                                    overlap/ownerless/path-existence green;         denial; refresh
                                    matrix += rung selection + SCM_RIGHTS[F5] +      status-preservation;
                                    per-tier RLS negatives + override-veto[B-1] +    no-status trigger/
                                    cross-workspace read[B-2] + backfill-order[B-3]  view/rule [F3,N-1,N-2];
                                    + ADOPTED continuous no-status scan[N-2,NB-1]    grant-delta zero-byte;
                                    + cross-workspace/NULL-GUC INSERT neg[B2-INSERT]
                              │                                                      dumpable=0 evidence
                        KBN-101-08 (dep 00…07,10): foundation + atomic activation cert
```

- **Gate A (re-review):** every element traces to a manifest owner; disjointness/overlap/ownerless proven against amended §7; the SPEC-vs-implement split for `tasks`+override sink DDL matches the frozen §4 L178 precedent (producer = KBN-100, applied **after** table creation — GA-1); dep edges acyclic with `10→01` import direction (AD-2/N-5); the L176 CONNECT amendment named (AD-1).
- **Gate B (red-team):** each B1/B2 finding **and** F1–F7 **and** B-1/B-2/B-3 **and** B2-INSERT **and** N-1..N-4 **and** NB-1..NB-5 **and** the Q2 per-tier deny-by-default has a **red-first** test that fails on the current design and passes only with the enforcement point; sink privilege/RLS/override/tenant denials — **including cross-workspace and NULL-GUC INSERT/UPSERT [B2-INSERT]** — proven **in PostgreSQL** (not PGlite — §5 L218); SCM_RIGHTS/dumpable against a real UID drop with an authenticated socket.

---

## 5. Executability self-audit (re-run for v5)

**Every element has an owner in the amended manifest — nothing ownerless:**

| Element                                                                                                                                                                                                                                                                                                                                                                                                                 | Owner                                                                                  |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- |
| Declarative RBAC policy artifact + schema [F6] + evaluator + ladder + no-status trigger/view/rule enum [N-1,N-2]                                                                                                                                                                                                                                                                                                        | KBN-101-10 (`packages/db/src/sink-rbac/**`)                                            |
| Rung→credential connection-selection module (consumes -01 pools; `10→01` [N-5])                                                                                                                                                                                                                                                                                                                                         | KBN-101-10; pools provisioned in KBN-101-01 (`database.module.ts`)                     |
| Status-preserving-UPSERT [F4] + invariant-set [F7] module                                                                                                                                                                                                                                                                                                                                                               | KBN-101-10 (`packages/db/src/sink-rbac/**`)                                            |
| SCM_RIGHTS handoff [F5] + non-dumpable assert/verify                                                                                                                                                                                                                                                                                                                                                                    | KBN-101-10 (`packages/db/src/credential-handoff/**`)                                   |
| Fixed rung DB roles + safe attributes [F2] + deny-default base + CONNECT + **[AD-1] L176 allowlist amend + TEMPORARY denial** + **[NB-5] baseline L176 runtime grants (`USAGE mosaic`, ledger `SELECT`, sequence grants) on the 2 new capability roles**                                                                                                                                                                | KBN-101-00 (`infra/pg-bootstrap/roles.sql` + tests) — **no tasks/override DDL [GA-1]** |
| `tasks` sink DDL: rung grants [F1,F7,N-3] + RLS `WITH CHECK`(+override) [Q2,B-1] + **INSERT `WITH CHECK` workspace bind on every rung [B2-INSERT]** + `SELECT`/`UPDATE` `USING` workspace predicate [B-2] + `FORCE RLS` terminal-after-backfill [B-3, conds a&b] + `(workspace_id,id)` UNIQUE [F4] + `actor_id` col [Q1] + no-status trigger/view/rule invariant on `tasks` **and override relation** [F3,N-1,N-2,NB-1] | **KBN-100 producer** (SPEC by -10; §4 L178 precedent; scope amended per Q2)            |
| **`task_status_write_override` table [B-1]** (create + grants + FORCE RLS + policies; User-write-only incl. **INSERT `WITH CHECK` workspace bind [B2-INSERT parity]**, all-rung-SELECT)                                                                                                                                                                                                                                 | **KBN-100 producer** (SPEC by -10; same L178 precedent)                                |
| `mosaic.workspace_id` session predicate set at checkout [B-2]                                                                                                                                                                                                                                                                                                                                                           | KBN-101-01 (`database.module.ts` / `connection-identity.ts`)                           |
| Rung DSN secret mounts (3 fixed)                                                                                                                                                                                                                                                                                                                                                                                        | KBN-101-05 (renderer, extends runtime-URL row)                                         |
| Checkout identity==rung + safe-attribute/non-owner verify [F2]                                                                                                                                                                                                                                                                                                                                                          | KBN-101-01 (`connection-identity.ts`, extended L222)                                   |
| Migrator launch wrapper SCM_RIGHTS send + dumpable re-assert                                                                                                                                                                                                                                                                                                                                                            | KBN-101-03 (`docker/db-migrator.Dockerfile` [GA-4(ii)])                                |
| Importer privileged-fd case                                                                                                                                                                                                                                                                                                                                                                                             | KBN-101-02                                                                             |
| Deployed enforcement certification (F3/N-1/N-2 **+ NB-1 override-relation scan**, per-tier RLS negatives, B-1 override-veto, B-2 cross-workspace read, **B2-INSERT cross-workspace/NULL-GUC INSERT negatives**, B-3 ordering + break-glass naming **incl. [NB-4] `mosaic_schema_owner` contained-but-capable / non-reachability assertion**, N-4 decision)                                                              | KBN-101-09 (evidence-only)                                                             |
| Inventory/overlap/path-existence + command matrix (rung sel + SCM_RIGHTS + per-tier RLS + override-veto + cross-workspace read + **[B2-INSERT] cross-workspace/NULL-GUC INSERT negatives** + backfill-order + **[ADOPTED] continuous no-status scan on `tasks` + override relation**)                                                                                                                                   | KBN-101-06 (fixture += -10)                                                            |

**Manifest closure (KBN-101-06 green):** the only NEW ownership is the two disjoint -10 globs. The B-1 override table, B-2 `USING` policies, B-3 terminal-FORCE ordering, **and the v4 B2-INSERT INSERT `WITH CHECK` workspace binding (+ its override-table parity) and the NB-1 override-relation no-status enumeration** are ALL producer DDL homed in KBN-100's already-owned `schema.ts`/`drizzle/**` (a _responsibility_ widening, not a glob change — identical treatment to the v3 `tasks` sink DDL). The **NB-5 baseline capability-role grants** amend -00's already-owned `roles.sql`/tests (like AD-1); the **continuous -06 no-status scan** lives in -06's already-owned `tools/ci/fixtures/kbn101-ddl-inventory.json` + `.woodpecker/ci.yml`; the NB-2/NB-3/NB-4 claim-scopings/enumeration are doc + -09 cert wording on already-owned paths. N-1/N-2/N-5 additions live in -10's already-declared `sink-rbac/**`. **No glob is split/shared/narrowed → overlap/ownerless/path-existence stay green (KBN-101-06 unchanged-green vs v3).**

**NO per-federated-user topology (HALT boundary respected — re-verified for v5):** DB-role/credential cardinality = **3** (User / Orchestrator / others), fixed and independent of the federated-user count. Federated identity → rung happens in the evaluator at authorization time. A new federated user creates **zero** roles/credentials/secrets/pools. The **B-1 override table is keyed `(workspace_id, task_id, tier)` — task+tier, never writer** — so it homes a tier-level veto, not a per-user distinction. The **B-2 read `USING` predicate AND the B2-INSERT INSERT check predicate are the SAME shared per-request session var** (`mosaic.workspace_id`), applied uniformly to whichever rung role holds the connection — tenant isolation, not writer discrimination (and, per v5, composed into a single compound check or `AS RESTRICTIVE` rather than an OR of separate permissive policies). Per-writer **attribution** is a metadata column (`task_events.actor_id`, §2.6), not a DB principal. `userOverride` forbids a per-writer authority key (F6, fail-closed at load). The NB-1..NB-5 fixes add no principal, key, or predicate that varies by writer. Enforce-at-sink is satisfied by the fixed rung roles' grants + `FORCE RLS WITH CHECK`(+override, +workspace-bound INSERT) + `USING` — it does **not** require, and this design does **not** use, a DB role/credential per federated user.

**Q1 same-tier / different-authority check (the ONLY HALT trigger):** no v5 change gives two SAME-TIER writers different WRITE authority. The v5 composition pin fixes only **how** the already-uniform predicates are physically composed (single compound `WITH CHECK` or `AS RESTRICTIVE`, never multi-permissive-OR) — it changes no predicate's content and introduces no writer-varying axis. F1/F2/F3/F7/N-3 tighten authority uniformly per tier; **B2-INSERT binds the same workspace predicate uniformly into every rung's INSERT check** (tenant isolation, not writer discrimination); B-1 vetoes the _entire_ Orchestrator tier per task (not a subset of Orchestrator writers); B-2 isolates by workspace uniformly; F6 forbids per-writer authority keys; attribution is audit-only. The NB-4-transitive nit only _strengthens_ the owner non-reachability assertion (transitive membership) — no authority axis. **No same-tier-different-authority requirement exists → NO HALT — an executable envelope is delivered.**

---

## 6. Flagged ambiguities in the frozen contract (for reviewer awareness)

1. **Sink identity of the status store.** The RBAC-guarded sink is `tasks.status`; legacy `mission_tasks.status` stays frozen read-only. Confirm no reviewer reads "raw sink" as the legacy column.
2. **Frozen "role graph unchanged" + "no RLS" + L176 CONNECT allowlist vs. the rulings.** SHARED-CONTRACT rc.5 L82/L88-90 froze the role graph and grant/revoke-only (no RLS); frozen §4 L176 froze the CONNECT allowlist. Jason B1 + Mos OPTION A add fixed rung-roles; **Mos Q2** authorizes RLS `WITH CHECK`/`USING` + `FORCE RLS` + the override table; **AD-1** amends the L176 allowlist for the 2 new logins. The rc.20 amendment text (§1.3/§1.4) records all three as deliberate, human-authorized departures. Reviewer should confirm rc.20 is **adopted** (not treated as a violation), that KBN-100's DDL scope is amended to include RLS + the override table on `tasks`, and that the -00 row amends the L176 allowlist.
3. **Natural-key column list for `tasks` (F4).** `tasks (workspace_id, id)` UNIQUE is asserted by the SI-001 pattern but must be **bound + created by KBN-100**. If KBN-100's `tasks` identity differs, the UPSERT natural key re-binds to `(id)` (spec-level, no HALT).
4. **Initial/terminal status values (F1/N-3).** F1 pins base new-row status to `backlog` (§5.4 L214); N-3 pins the Orchestrator's INSERT set to non-terminal (`{backlog, ready}`) and reserves terminal (`{done, cancelled}`; `in_review` treated as non-initial) to the User rung. KBN-100 binds the exact column DEFAULT and the RLS `WITH CHECK` literals against the §3 L134 vocabulary so they agree.
5. **Workspace session-var name + set-site (B-2 + B2-INSERT).** The `USING` predicate **and the v4 INSERT `WITH CHECK` predicate** both use `current_setting('mosaic.workspace_id', true)`. -01 sets it per request from the server-verified tenant (never a body field, §7.1). Reviewer should confirm the exact GUC name and that a transaction-local `SET LOCAL` is used so a pooled connection cannot leak a stale workspace across requests (mirrors the frozen `SET LOCAL search_path` discipline, §4 L152) — now **explicitly folded into the frozen L174 poisoned-pooled-session-reset + `SET LOCAL` restoration negative test** (Gate B 2(a), §2.2). Reviewer should also confirm the accepted scope (NB-3): fail-closed on an omitted/NULL GUC (buggy Gateway), but a _forged_ GUC to a victim tenant is the accepted per-user residual (Mos Q1), not defended.
6. **N-4 transition-graph decision.** Edge-legality (illegal/backward transitions such as `done→backlog`) is **app-enforced** within near-god/god authority; the sink closes RC19-B1-02 for **base only** (DELETE-denial + no base status write). A validation-only sink guard is deferred to avoid colliding with the F3/N-2 no-status-trigger invariant. Reviewer should confirm this decision is acceptable (it is stated, not silently dropped).
7. **N-2 continuous scan — now ADOPTED.** The complete no-status-write enumeration (trigger/view/rule/SECURITY DEFINER/function-body), covering `tasks` **and `task_status_write_override` (NB-1)**, is now a **continuous -06 CI catalog scan run on every migration** (promoted from the v3 one-shot -09 recommendation, per Gate A-delta-2 obs #2); the -09 deployed cert still records the final proof. Reviewer should confirm the -06 scan is owned/wired in `tools/ci/fixtures/kbn101-ddl-inventory.json` + `.woodpecker/ci.yml` (already-owned -06 paths).
8. **KBN-101-09 is evidence-only.** B-1/B-2/B-3/F3/N-1/N-2 negative tests are _authored/owned_ by the producing implementation cards (KBN-100 producer for `tasks`/override triggers/RLS; -10/-01 for the rung path); KBN-101-09 records the **deployed** certification evidence and changes no implementation path. Confirm the test-ownership split is acceptable (mirrors the frozen -09 "evidence-only" role).
9. **B2-INSERT / B-1 `WITH CHECK` composition — SEMANTICS CORRECTED + REALIZATION MANDATED (v5; the delta-3 fix).** v4 justified the composition with a **FALSE** PostgreSQL claim — "multiple applicable `WITH CHECK` clauses must all pass (they AND)". **That is struck.** The **correct** semantics: multiple **PERMISSIVE** policies for a command combine with **OR** (a row is admitted if it satisfies **ANY** one permissive `WITH CHECK`, ANDed with all `AS RESTRICTIVE` checks); the AND this closure needs holds **ONLY** (a) within a _single_ policy whose `WITH CHECK` is one AND-conjoined expression, or (b) across `AS RESTRICTIVE` policies. Accordingly v5 **MANDATES** (§1.4 item 3-bis / §2.4 clause 5 / §2.9) that, per rung per command, the status-pin **AND** the workspace-bind **AND** (Orchestrator) the override subquery be realized as EITHER a **single compound `WITH CHECK`** OR the status-pin-as-sole-permissive **plus** the workspace-bind/override **`AS RESTRICTIVE`**, and **EXPLICITLY FORBIDS** realizing them as multiple _permissive_ policies intended to AND (which would OR-admit a foreign-workspace INSERT satisfying only the status-pin — cross-tenant injection — and equally bypass the B-1 veto). Reviewer should confirm: (i) the corrected OR-semantics statement replaces every "all `WITH CHECK` AND" assertion; (ii) the realized policies are single-compound or `AS RESTRICTIVE` (a `pg_policy.polpermissive` catalog check backs it); (iii) the hardened red-first negatives use an _otherwise-valid_ row (cross-workspace: base + `backlog` + foreign ws; override: an otherwise-accepted Orchestrator transition) so each rejection isolates the bind/override under test, **and each carries a positive-control** (dropping the workspace conjunct — resp. the override subquery — alone flips the negative to a PASS, proving the bind/override, not the status-pin, is rejecting). Confirm the accepted scope (NB-2/NB-3) is unchanged: write-side sink tenant isolation is complete against a _buggy_ Gateway; a _compromised_ Gateway forging the GUC or holding the User pool is the accepted Mos Q1 residual.

---

_Envelope A **v6** authored from base `b0d78d86`. **v6 = v5 + N1/N2/F-NB4 non-blocking test/lint/cert hardening ONLY — NO design predicate, policy, grant, role, or table is changed** (only test/lint/cert wording). v5 CONVERGED with BOTH terminal re-gate-4 gates GO (Gate A-delta-4 `a4ce075a`; Gate B-delta-4 `a379e0de`), NO HALT; Gate B-delta-4 flagged 3 EXPLICITLY NON-BLOCKING hardening notes "for the trunk-commit record," folded here additively: **N1** — the `pg_policy.polpermissive` lint is strengthened to count permissive policies grouped by EFFECTIVE role (incl. `PUBLIC`/inheritance) and to reject an internally-disjunctive single `WITH CHECK`, stated as SUPPLEMENTARY with the behavioral positive-controls remaining the PRIMARY proof (§1.4 item 3-bis / §2.4 clause 5 / §2.7 / §3 Q2 row); **N2** — the option-(b) vacuous-deny guard is stated explicitly as the load-bearing "≥1 PERMISSIVE policy per writable (rung, command)" invariant, verified by the "same-workspace valid-status write succeeds" positive tests for INSERT / transition-UPDATE / SELECT (§1.4 item 3-bis / §2.4 clause 5 / §3 Q2 row); **F-NB4** — owner non-reachability is extended to SET-ROLE assumability by conjoining the `MEMBER` variant `NOT pg_has_role(<rung>, 'mosaic_schema_owner', 'MEMBER')` AND `NOT pg_has_role(<rung>, 'mosaic_migrator', 'MEMBER')` for each of the 3 runtime rungs in the -09 cert (§1.4 NB-4 para / §3 NB-4 row). All three are assertion/test/lint completeness on an already-BOTH-GO design; the intended role graph is already safe. The v6 body otherwise preserves the v5 text verbatim, which in turn preserved EVERY v4 closure (all v4 checks passed except one bounded item) and closed the SINGLE remaining BLOCKING finding raised identically by BOTH re-gate-3 gates (Gate A-delta-3 `aa5cbf73` CHANGES-NEEDED; Gate B-delta-3 `aa881074` 1 blocking) — the **RLS `WITH CHECK` composition semantics**: (1) **corrected semantics** — struck the FALSE "PostgreSQL requires ALL applicable `WITH CHECK` to pass / they AND" from §1.4/§2.4/§6.9 and stated the true rule (multiple PERMISSIVE policies OR; AND holds only within a single compound `WITH CHECK` or across `AS RESTRICTIVE`); (2) **mandated the realization** — per rung per command, status-pin + workspace-bind + (Orchestrator) override subquery MUST be a **single compound `WITH CHECK`** OR the status-pin-as-sole-permissive **plus** the bind/override **`AS RESTRICTIVE`**, with **multi-permissive-intended-to-AND EXPLICITLY FORBIDDEN**, applied to `tasks` **and** `task_status_write_override` (§1.4 item 3-bis, §2.4 clauses 4–5, §2.9); (3) **hardened the red-first negatives** — cross-workspace INSERT uses an otherwise-valid row (base + `backlog` + foreign ws) and the B-1 override negative uses an otherwise-accepted Orchestrator transition, so each rejection isolates the bind/override, **each with a positive-control** (dropping the workspace conjunct — resp. override subquery — alone flips the negative to PASS); plus **NB-4-transitive** (owner non-reachability stated as TRANSITIVE membership — `NOT pg_has_role(...)`/`has_privs_of_role(...)` recursion, not a direct `pg_auth_members` edge; frozen L222 "assumability" noted as plausibly already covering it). Every other v4 closure carries forward intact (3-rung ladder / 0 per-user; F1–F7; GA-1/3/4; B-1/B-2/B-3; the B2-INSERT workspace bind itself; N-1..N-5; AD-1/AD-2; NB-1..NB-5; continuous -06 no-status scan; L174 poisoned-pool `SET LOCAL` GUC fold; rc.20). Manifest disjoint (KBN-101-06 green) — all v5 changes land on already-owned KBN-100-producer / -09 / -06 paths (DDL realization detail + test wording; no glob change). Design/contract only; no SSOT file modified, no code, no PR. HALT self-check: NO HALT (fixed 3-rung ladder; override keyed task+tier not writer; workspace predicate shared per-request and uniform per tier, now composed as single-compound/`RESTRICTIVE`; attribution → metadata; no per-federated-user DB role/credential; no same-tier different-authority requirement — both delta-3 gates independently confirmed the boundary HOLDS). **v6 changes NOTHING in this HALT calculus: N1/N2/F-NB4 add only lint-scope, a vacuous-deny test invariant, and a `MEMBER` assumability assertion — zero new principal, key, predicate, grant, role, or table, and no writer-varying axis — so NO HALT is re-confirmed for v6.** Manifest remains disjoint (KBN-101-06 green): every v6 fold lands on already-owned paths — the -06 continuous scan / `pg_policy.polpermissive` lint in `tools/ci/fixtures/kbn101-ddl-inventory.json` + `.woodpecker/ci.yml`; the option-(b) positive tests in the KBN-100-producer / -09 evidence paths; the `MEMBER` assertion in the -09 cert — no glob split/shared/narrowed. NO code, NO PR, NO SSOT edit._
