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+# approval-queue runbook — executor rail as approval-request queue (REQ-27, P04-04)
+
+The executor rail (LXC 116 coreci-executor + LXC 117 coreci-broker) stays
+RUNNING at all times; its job is to park, route, decide, mirror and report
+approval requests. It never executes anything (README "The NEVER-EXECUTES
+guarantee"). This repo is frozen: the change that repurposes it IS the PR
+holding this file + `allowlist.yaml` v5.0 + `routing.json`.
+
+## Queue model
+
+- Request: a credential-free envelope from an acting employee's pipeline
+  (`POST /submit_request`, EXECUTOR_API_KEY auth). Fields: `id`,
+  `requestor` (Gitea username = seat), `system_id` (optional — a
+  systems-ownership row id), `title`, `class` (L1|L2|L3), `justification`
+  (+ legacy-compat `kind`/`targets`/`content` for the UI display).
+- Routing: resolved at intake from `/config/routing.json` (GENERATED from
+  coreci/company org records — never hand-edited here):
+  lane `chairman-direct` (C-09: acting C-suite + CEO + coreci-sre →
+  Chairman decides), lane `manager:owner` (requestor's manager one hop +
+  the touched system's owner; both when both, deduped, manager listed
+  first), lane `skip-path` (unresolvable chain → approver CEO, queue
+  Chairman — sanctioned skip-path 2). No ownership-table row for a
+  submitted `system_id` → request REFUSED at intake (fail-closed).
+  Full trail (rule-by-rule, with timestamps) is stored on the request
+  and mirrored to the Gitea issue.
+- Approval: the resolved approver decides at the executor UI
+  (`/ui/request/{rid}/approve|deny`, passcode session). Approve/deny is a
+  DECISION-RECORD only — the legacy approve-triggers-run path is disabled
+  in approval-queue mode (0.4.0 decision-only server build; see "Apply").
+- Result: `GET /request_status?request_id=…` returns
+  `{status: open|routed|decided, decision, decided_by, decided_at, …}` —
+  the requesting pipeline polls this, never the queue's internals.
+- Audit: every event is appended to `logs/audit-YYYY-MM-DD.jsonl`
+  (append-only, git-durable) with the vocabulary
+  `request.created, route.resolved, decision.posted, mirror.updated`.
+  `/ui/audit` renders recent rows for humans.
+
+## Issue mirror (coreci/meetings)
+
+The queue posts one issue per request into coreci/meetings — the same
+lane the meeting machinery's approval-requests already live in — labels
+`approval-request` + `approval:L2|L3` + `dept:<dept>`; body carries the
+machine-notes block (`requestor: / system: / owner: / lane: / status:`).
+Decisions are posted as comments by the EXECUTOR APP ACCOUNT
+(`coreci-executor`, its own PAT) and the body flips to
+`status: decided (…)`. Idempotency: the mirror dedups on the request id
+token in the issue body (`ar-…`); a mirror-retry can never double-post a
+request or a decision. Full contract:
+coreci/sre `scripts/p04-executor/mirror-contract.md`.
+
+## Apply the change (operator-gated, on-host — NO pipeline does this)
+
+The rail hot-reads this repo's config ONLY through its bind mount —
+there is no redeploy pipeline watching this repo; nothing applies until
+the operator runs the steps below (read-only from SRE's side: the sre
+repo only AUTHORS the patch and opens the PR).
+
+1. PR merged into executor-config:main (merge = the operator's
+   confirmation; the merge itself changes the frozen repo's files).
+2. On LXC 116, in the executor-config working copy mounted at
+   /config (and the container's own clone):
+
+       git fetch --all && git pull --ff-only
+   - `allowlist.yaml` v5.0 takes effect on the NEXT classification pass
+     (the legacy classifier hot-reads per call — `current_allowlist()`
+     opens the file every time: NO restart needed), so the last auto-run
+     grants die the moment main updates.
+3. Server build to 0.4.0 (decision-only / never-executes). IMPORTANT
+   recon fact: the LIVE server (0.3.0) is NOT built from this repo's
+   stale `app/main.py` (repo app = v0.1.1 classifier module only). The
+   0.4.0 build must be produced from the on-host source of truth, wire
+   it: read `ALLOWLIST_PATH=/config/allowlist.yaml` (repo-mounted) and
+   `EXECUTOR_ROUTING_TABLE=/config/routing.json`, honor
+   `mode: approval_queue_only` (refuse to boot without it or without
+   `never_execute: true` — fail-closed), run the routing + mirror half
+   from this runbook + the mirror contract. Then:
+
+       podman compose up -d --build    # or docker compose
+       curl -s http://127.0.0.1:8765/health
+       -> expect {"status":"ok","version":"0.4.0","mode":"approval_queue_only",...}
+4. LXC 117 (coreci/broker) is UNTOUCHED by this repurpose (broker repo
+   frozen; its change channel is a separate one-way PR when needed).
+5. Post-apply asserts (all must be GREEN): `GET /health` version 0.4.0;
+   `GET /request_status?request_id=probe` → 404-with-id (queue reachable,
+   no phantom request); executor identity can create/label issues in
+   coreci/meetings; executor identity CANNOT write any other repo
+   (negative assert — try a write via the API and expect 403); audit
+   JSONL gains the 4-event vocabulary on a test request; mirror issue
+   appears with the machine-notes block; decision on the test request
+   mirrors correctly and body flips status.
+
+## Rollback
+
+Revert the merged PR (one-way channel: a revert PR), keep the 0.4.0
+server: it boots fail-closed WITHOUT `mode: approval_queue_only` — with
+the v4.1 allowlist restored the legacy classification semantics return,
+and nothing auto-runs (all grants were revoked in this repurpose; that
+revocation stands until org records say otherwise via new org-record PRs).
+
+## Escalation
+
+Executor unreachable → notify-ladder (bao KV) as usual; queue outages
+NEVER auto-approve: pipelines wait on `request_status`, and an outage
+shows as `routed`/`open` with a heartbeat gap in the audit trail.
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