I've created a networking library in C++ which works on Linux, Windows, & MacOS and made the core of it based on C++ coroutines and native asyncio from each of these platforms. Check it out: https://github.com/adityarao2005/WebCraft.
Unfortunately, the only examples of it in use are in the test cases but I plan on adding examples soon.
WebCraft: A C++ 23 async based networking library (which does not use Boost) | Heykuki News