• Status: Proposed implementation.
• Owner: Jon.
• Sources checked: hooks/depcruiser-authored-graph-contract-simplified/index.mdx, .../v3-hooks-aligned-runtime.mdx, E:/hooks/depcruiser-migrations/ (current files), E:/hooks/_docs/depcruiser-migrations-design-and-verification.md and _supplement.md, E:/hooks/config.json, E:/hooks/_core/config-model.mjs, E:/hooks/quality-completion-gate/quality-verify-manifest.json, E:/hooks/.state/.

This page proposes the P0 depcruiser runtime as one buildable cut. It keeps the simplified hooks-aligned file footprint and specifies three enforcement properties the runtime must hold: node completion is declared as data in graph.contract.json; guarded target edits are gated on an approval hash, not on the current node label; and the active migration state is written only by runtime subcommands, never by hand.

Files The Proposed Plan Would Create

Retire after the replacement passes its tests, in one controlled commit: closure-gate.mjs, closure-gate-core.mjs, closure-gate.register.json.

Runtime State And Evidence (created by the runtime, not authored)

Graph Contract (data)

{
  "version": 1,
  "nodes": [
    { "id": "discovery",           "requiredOutputs": ["active.json"],                              "predicate": "activeStateValid" },
    { "id": "manifest_generation", "requiredOutputs": ["before-edit.donor.json", "source-manifest.json"], "predicate": "manifestHasAllModules" },
    { "id": "adjudication",        "requiredOutputs": ["adjudication.json"],                        "predicate": "noTbdVerdicts" },
    { "id": "approval",            "requiredOutputs": ["approval.json"],                            "predicate": "approvedHashMatchesManifest" },
    { "id": "implementation",      "requiredOutputs": [],                                           "predicate": "allApprovedTargetsExist" },
    { "id": "closure_verification","requiredOutputs": ["after-edit.target.json"],                   "predicate": "verifyActiveClosureExit0" },
    { "id": "final_approval",      "requiredOutputs": [],                                           "predicate": "finalApprovalEventRecorded" },
    { "id": "disarm",              "requiredOutputs": [],                                           "predicate": "activeStateCleared" }
  ],
  "transitions": [
    ["discovery", "manifest_generation"],
    ["manifest_generation", "adjudication"],
    ["adjudication", "approval"],
    ["approval", "implementation"],
    ["implementation", "closure_verification"],
    ["closure_verification", "final_approval"],
    ["final_approval", "disarm"],
    ["closure_verification", "implementation"],
    ["closure_verification", "adjudication"]
  ]
}

The runtime reads this file to know each node's required outputs and completion predicate. Advancement is decided by artifact existence plus predicate result, never by turn count. The two back-edges from closure_verification carry in-scope debugging (to implementation) and scope changes that need re-approval (to adjudication).

Runtime Behavior, Node By Node

Gate Invariants

The PreToolUse decision for Edit, Write, MultiEdit, NotebookEdit, and apply_patch:

1. No active.json → allow (no migration armed).
2. active.json invalid, or past expiresAt → deny guarded edits with a repair instruction.
3. Edit path outside targetRoot, or not under guardedPrefixes/guardedFiles → allow.
4. Guarded edit while approval.json is missing or its approvedManifestHash does not equal the current manifest hash → deny, inject the current node.
5. Guarded edit to a path that is not an approved port/adapter target_path → deny.
6. apply_patch → extract every header path and apply rules 3–5 to each.

The gate always exits 0; failPolicy: open covers script crashes, but a known-invalid armed state is an intentional deny.

Config Entry

Added only after depcruiser-migrations.mjs exists. No config.schema.json regeneration is required because hook settings is a generic object and no hook-specific schema is introduced.

{
  "id": "depcruiser-migrations",
  "name": "Depcruiser Migrations",
  "description": "PreToolUse gate and CLI for governed dependency-cruiser migrations.",
  "category": "gate",
  "event": "PreToolUse",
  "match": { "tools": ["Edit", "Write", "MultiEdit", "NotebookEdit", "apply_patch"] },
  "script": { "path": "depcruiser-migrations/depcruiser-migrations.mjs", "runtime": "node" },
  "scope": { "projects": ["*"], "paths": ["**"] },
  "enabled": false,
  "failPolicy": "open",
  "settings": {
    "stateDir": "E:/hooks/.state/depcruiser-migrations",
    "editTools": ["Edit", "Write", "MultiEdit", "NotebookEdit", "apply_patch"]
  }
}

Implementation Sequence

1. depcruiser-migrations.mjs + lib/state-store.mjs + lib/path-scope.mjs: unarmed allow, invalid-state deny, guarded-path matching, apply_patch path extraction.
2. graph.contract.json with the eight nodes and predicates.
3. Strengthen validate-closure-manifest.mjs to repo-relative, blocking reconcile with target_extras.
4. verify-active-closure.mjs.
5. One focused test file (state, matching, apply_patch, approval-hash gate, reconcile).
6. Add the disabled config hook entry; run _core/validate-runtime-hooks.mjs (no schema regen).
7. Retire the closure-gate* files only after the new runtime passes.