[merb]

the plaintext c# one actually only sets a content length manually since without it it would be a streaming response (Transfer-Encoding: chunked), which would not make the server slower, but the client, because of buffers (also as far as I know the Content-Length needs to be set in this benchmark). btw. go does not do that when calling w.Write without wrapping the responsewriter inside a buffer (which is probably also the case why it is slower, since it needs to know the size of the written response before it goes over the network and btw. only go-std is slow because it's written for simple use cases, there are others like fasthttp who do stuff a little bit more like c# and thus are faster (even inside ;-) go-std never cared about being the fastest.)