What about Ktor? I always see that being pushed, maybe because it's from Jetbrains..
I often wonder why people always post these "sure, but what about..." replies. Hot take: There's more than one way to skin a cat, here's one.
1. The post is already about an alternative to the mainstream (Spring), so adding another alternative seems perfectly valid.
2. I know neither Spring nor this alternative, but want to add the one framework I know of. This gets increasingly popular after previous 1./2. responses.
3. My/my company's badly tested pet library, let me show you it.