New `encoding/json/v2` package (hidden behind `GOEXPERIMENT=jsonv2` flag)! It brings perf improvements and finally allows devs to implement custom marshalers for external types:
> Alternatively, users can implement functions that match MarshalFunc, MarshalToFunc, UnmarshalFunc, or UnmarshalFromFunc to specify the JSON representation for arbitrary types. This provides callers of JSON functionality with control over how any arbitrary type is serialized as JSON.
> Alternatively, users can implement functions that match MarshalFunc, MarshalToFunc, UnmarshalFunc, or UnmarshalFromFunc to specify the JSON representation for arbitrary types. This provides callers of JSON functionality with control over how any arbitrary type is serialized as JSON.
Awesome stuff.