{
  "schema": {
    "firstname": { "type": "string", "title": "First name" },
    "lastname":  { "type": "string", "title": "Last name" },
    "fullname":  { "type": "string", "title": "Full name" }
  },
  "form": [
    "firstname",
    "lastname",
    {
      "key": "fullname",
      "value": "{{values.firstname}} {{values.lastname}}"
    }
  ],
  "value": {
    "firstname": "François",
    "lastname": "Daoust"
  }
}