[hocuspocus]

I use Tapir with http4s as the http server isn't my bottleneck anyway and I like Cats Effect and fs2.

But SoftwareMill has done extensive benchmarking to make sure the overhead from Tapir vs calling the http backend directly was insignifiant. I believe Netty is the recommended backend if you want direct style (i.e no effect systems) on Java 21+ virtual threads even though Oracle's Helidon Níma is supported too.

[KajMagnus]

Thanks! Ok, seems direct style is what I would want, after having asked an LLM: it says it's then simpler to debug async call stacks, with Java 21+ virtual threads.

Nice to know that there are good alternatives, if time it is some day to migrate away from Play.