{
  "id": "simulation_dry_run_engine",
  "label": "Simulation / Dry-Run Engine Canonical",
  "phase": "phase-09",
  "category": "operational_flows",
  "status": "ACTIVE_DH_MIRROR",
  "purpose": "Evaluate operational impact before mutation or release.",
  "function": "Expose conflicts, expected deltas, affected surfaces and rollback needs before live execution.",
  "technology_requirements": [
    {
      "technology": "Dry Run Execution Sandbox",
      "required_for": "Evaluate operational impact before mutation or release.",
      "required_by_phase": "phase-09",
      "required_by_category": "simulation_dry_run_engine",
      "required_by_buckets": [
        "Prerequisites",
        "Installation",
        "Configuration",
        "Validation",
        "Observable Evidence",
        "Failure Modes & Recovery",
        "Completion & Promotion"
      ],
      "expected_version": "MISSING until Dry Run Execution Sandbox is implemented and validated in the future Execution & Monitoring Panel",
      "validation_command": "MISSING until simulation_dry_run_engine can prove scope, evidence, execution state and promotion decision",
      "evidence_path": "/home/yeff/public_html/devon/canon/execution/state/dh_sources/simulation_dry_run_engine.json",
      "status_source": "Documentation Hub + future Execution & Monitoring Panel",
      "blocking_if_missing": true,
      "failure_impact": "Dry-run failure is not delay; it is avoided damage. A conflict found before mutation is a cheap signal. The same conflict discovered after write, migration or deploy becomes incident response. This category converts foreseeable risk into pre-execution evidence."
    }
  ],
  "depends_on": [
    "planning_reasoning",
    "filesystem_operations",
    "diff_patch_replace_engine"
  ],
  "used_by": [
    "production_deployment_gate",
    "migration_runner",
    "release_governance"
  ],
  "overview": {
    "summary": "Simulation / Dry-Run Engine Canonical owns the rehearsal layer of DEVON-DEV operations. It is not a comfort check; it is the mechanism that makes risky actions prove their blast radius before they touch live state.",
    "function": "FUNCTION: Run non-destructive evaluation for patches, commands, migrations, integrations and releases, exposing affected files, expected deltas, missing prerequisites, conflicts and rollback requirements.",
    "system_position": "This category is the operational counterweight to speed. Planning Reasoning may define a route, but dry-run evidence proves whether that route is safe enough to execute. Production Deployment Gate and Migration Runner should treat this output as preflight evidence, not optional hygiene.",
    "failure_impact": "Dry-run failure is not delay; it is avoided damage. A conflict found before mutation is a cheap signal. The same conflict discovered after write, migration or deploy becomes incident response. This category converts foreseeable risk into pre-execution evidence."
  },
  "failure_impact": "Dry-run failure is not delay; it is avoided damage. A conflict found before mutation is a cheap signal. The same conflict discovered after write, migration or deploy becomes incident response. This category converts foreseeable risk into pre-execution evidence."
}