I figured this might be useful to some of you - more than once I've had a project that uses Protobuf without gRPC, and developing against Protobuf over HTTP services has been a bit tiresome due to lack of tooling - this seeks to solve that issue to an extent. Use a client like Postman or Insomnia to send JSON requests to an HTTP endpoint, specify the protobuf mesaage types, and let this proxy handle the rest. No more manual encoding/decoding/general unwanted friction.