A great feature of pydantic are the validation hooks that let you intercept serialization/deserialization of specific fields and augment behavior.

For example if you are querying a DB that returns a column as a JSON string, trivial with Pydantic to json parse the column are part of deser with an annotation.

Pydantic is definitely slower and not a 'zero cost abstraction', but you do get a lot for it.

One approach to do that in msgspec is described here https://github.com/jcrist/msgspec/issues/375#issuecomment-15...