Rapidjson had its last versioned release 3 years ago, its primary maintainer is no longer active and it has failed to pass an internal security review. Its internal use is frozen and the recommendation is to move to gRPC's json parser: https://github.com/grpc/grpc/blob/master/src/core/lib/json/json.h