I love that this library provides good platform compatibility and the ability to extend its transport. But the wire format is fixed to JSON.

I wonder if it can provide the ability to customize (de)serializer, or even the entire (De)evaluator implementation as well, for example:

declare interface Serializer;

newWebSocketRpcSession("wss://example.com/api", {
  serializer: myCustomSerializer,
});

To allow compacting or compressing wire messages?