The encoding/json package marshals RawMessage properly or incorrectly as base64 based on whether its container is marshaled by value or as a pointer, which is extremely subtle and trivial to get wrong silently.
It also consistently fails to marshal the RawMessage value properly when used as a map value type.
Sample code demonstrating these problems:
https://play.golang.org/p/bHuvfyb7qB
The encoding/json package marshals RawMessage properly or incorrectly as base64 based on whether its container is marshaled by value or as a pointer, which is extremely subtle and trivial to get wrong silently.
It also consistently fails to marshal the RawMessage value properly when used as a map value type.
Sample code demonstrating these problems:
https://play.golang.org/p/bHuvfyb7qB