[
  {
    "operation": "remove",
    "spec": {
      "_id": "",
      "friends": "",
      "favoriteFruit": ""
    }
  },
  {
    "operation": "shift",
    "spec": {
      "name|gender|age": "personal_details.&0",
      "company|email|phone": "contacts.&0",
      "balance": "balance"
    }
  },
  {
    "operation": "default",
    "spec": {
      "account_type": "CHECKING"
    }
  }
]