Full-duplex over WebSocket

Client and server in one package, with transport fallback WebSocket → SSE → Long Polling.

JSON & MessagePack protocols

Both the 0x1E-delimited JSON protocol and the VarInt length-prefixed MessagePack protocol.

Stateful reconnect

useAck / Ack / Sequence message buffering preserves in-flight messages across transport drops, interoperating with ASP.NET Core.