To quote one of the maintainers of the golang/protobuf implementation: > The jsonpb package is intended to the be faithful implementation of the proto<->JSON s

To quote one of the maintainers of the golang/protobuf implementation: > The jsonpb package is intended to the be faithful implementation of the proto<->JSON specification, for which the C++ implementation is considered the canonical "reference" implementation. And that C++ implementation does some kinda dumb things. For example, it marshals the protobuf type of int64 into a string when marshaling from a protobuf struct into JSON. https://github.com/golang/protobuf/pull/916 https://github.com/golang/protobuf/pull/916 I believe that the package they mention there is meant to be a more "canonical" protobuf <-> json marshaller than the existing jsonpb package.