We have such options in Fury too. We support register classes. In such cases, such string will be encoded with a varint id. It's kind of dict encoding. But not all users like to register classes. Meta string will try to reduce space cost when such dict encoding are not available.

Your suggestions are great. I should clarify why dict encoding can't be used to recude cost.

As for performance, it won't be an issue. The string for meta encoding are limited, we can cache the encoded result. So it's not in critical path