I know of the techempower benchmarks. You'll notice that the go results that end up scoring highly are using "atreugo", a customized low allocation implementation. That's how it gets its speed. Java and C# on the other hand are using fully fledged framework implementations (e.g. Vertx or ASP.NET).

You end up with a highly customized implementation not suited for wide use to get the higher performance benefits (and it still doesn't beat java on benchmarks like single/multiple queries and JSON serialization).

All these benchmarks should be taken with a large grain of salt. The golang compiler doesn't even pass function variables in registers (they're all stack allocated as far as I know), let alone do any of the advanced inlining and optimizations the JVM does.

This is not accurate, if you look at the dependencies of the project: https://github.com/savsgio/atreugo/blob/master/go.mod it uses well known libs like github.com/valyala/fasthttp.

Which is still a specialized library, and not widely used like golangs standard library. And comes with its own set of disadvantages

Vertx is not part of the standard library either, saying that Fast HTTP is a spezialized lib is very missleading since it's widely used.

This talk is by the author of fasthttp[1]. Note the caveats that come with it. Also, it is nowhere near as widely used nor established as Vertx.

[1] https://docs.google.com/presentation/d/e/2PACX-1vTxoBN41dYFB...