{
  "type": "object",
  "version": "1.0.0",
  "description": "User schema with default values",
  "properties": {
    "username": {
      "type": "string",
      "description": "Unique username"
    },
    "active": {
      "type": "boolean",
      "default": true,
      "description": "Whether the user account is active"
    },
    "role": {
      "type": "string",
      "default": "user",
      "description": "User role"
    },
    "created_at": {
      "type": "string",
      "description": "Account creation timestamp"
    }
  },
  "required": [
    "username"
  ]
}