{
  "id": "migration_runner",
  "label": "Migration Runner Canonical",
  "phase": "phase-09",
  "category": "delivery_layer",
  "status": "ACTIVE_DH_MIRROR",
  "purpose": "Execute approved migration steps with evidence and rollback trace.",
  "function": "Run migrations in governed order with command output, target environment, backup reference and validation result.",
  "technology_requirements": [
    {
      "technology": "Migration Runner",
      "required_for": "Execute approved migration steps with evidence and rollback trace.",
      "required_by_phase": "phase-09",
      "required_by_category": "migration_runner",
      "required_by_buckets": [
        "Prerequisites",
        "Installation",
        "Configuration",
        "Validation",
        "Observable Evidence",
        "Failure Modes & Recovery",
        "Completion & Promotion"
      ],
      "expected_version": "MISSING until Migration Runner is implemented and validated in the future Execution & Monitoring Panel",
      "validation_command": "MISSING until migration_runner can prove scope, evidence, execution state and promotion decision",
      "evidence_path": "/home/yeff/public_html/devon/canon/execution/state/dh_sources/migration_runner.json",
      "status_source": "Documentation Hub + future Execution & Monitoring Panel",
      "blocking_if_missing": true,
      "failure_impact": "The runner is where migration governance becomes irreversible action. Its danger is not only failed SQL or broken scripts; it is untraceable sequence. This category makes each migration step reconstructable before the data layer is asked to trust it."
    }
  ],
  "depends_on": [
    "database_migration_governance",
    "shell_execution",
    "backup_rollback"
  ],
  "used_by": [
    "production_deployment_gate",
    "disaster_recovery",
    "release_governance"
  ],
  "overview": {
    "summary": "Migration Runner Canonical owns execution of approved data change. It is not the judge of migration safety; it is the mechanism that proves a governed migration ran exactly as authorized.",
    "function": "FUNCTION: Execute migrations with migration id, ordered step, target environment, dry-run reference, backup reference, command output, validation result and rollback trace.",
    "system_position": "Database & Migration Governance defines what may run. Shell Execution performs the command. Terminal Output Panel captures output. Production Deployment Gate consumes migration status before permitting release.",
    "failure_impact": "The runner is where migration governance becomes irreversible action. Its danger is not only failed SQL or broken scripts; it is untraceable sequence. This category makes each migration step reconstructable before the data layer is asked to trust it."
  },
  "failure_impact": "The runner is where migration governance becomes irreversible action. Its danger is not only failed SQL or broken scripts; it is untraceable sequence. This category makes each migration step reconstructable before the data layer is asked to trust it."
}