[
  {
    "bases": [
      "DefaultParent"
    ],
    "fields": [
      "before",
      "value",
      "after"
    ]
  },
  {
    "payload": {},
    "source": {
      "before": 10,
      "value": 2,
      "after": 30
    },
    "generated": {
      "before": 10,
      "value": 2,
      "after": 30
    }
  }
]