{
  "objects": [
    {
      "$find": [
        {
          "path": "definition.archetype",
          "value": "Caboose"
        }
      ],
      "definition": {
        "loadSlots": [
          {
            "$add": {
              "maximumCapacity": 8,
              "loadUnits": "Quantity",
              "requiredLoadIdentifier": "crew-hours"
            }
          }
        ]
      }
    }
  ]
}