No one is picking Nodejs for high performance, but when it is chosen for other reasons it's still expected to perform well. The Nodejs gRPC library performs poorly relatively to the overall performance characteristics of Nodejs, and this is a problem because most of the work performed by typical Nodejs services is API-related work (sending data, encoding and decoding payloads, managing sockets etc). That's not even touching on the bugs in the http2 implementation in node core or the grpc library itself, but much of the selling point of gRPC is supposedly the language interop, and this seems like false advertising to me.