{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "allOf": [
    {
      "$ref": "#/definitions/myType"
    }
  ],
  "definitions": {
    "myType": {
      "type": "object",
      "properties": {
        "dog": {
          "type": "string"
        }
      },
      "required": ["dog"]
    }
  }
}