code: func FastUnmarshal(data []byte, v interface{}) error {
  	iter := jsoniter.ConfigFastest.BorrowIterator(data)
  	defer jsoniter.ConfigFastest.ReturnIterator(iter)
  
  	iter.ReadVal(v)
  	if iter.Error != nil {
  		return trace.Wrap(iter.Error)
  	}
  
  	return nil
  }
docs: // FastUnmarshal uses the json-iterator library for fast JSON unmarshalling.
  // Note, this function marshals floats with 6 digits precision.