Networking is a main sell of boost::asio but it does general async event loops, not only for networking. And boost::asio was upgraded for C++11 years ago.
I recently wrote a blog post discussion why I created Dasynq, here: https://davmac.wordpress.com/2017/12/17/introducing-dasynq/
Though I don't specifically discuss boost::asio there, I believe some of the points made there apply. Also, last time I checked, boost::asio mandated linking with threads library (at least for some features) whereas Dasynq doesn't, and boost::asio didn't offer support for watching POSIX signals or child process termination (Dasynq does). Finally, the boost::asio multi-threading model is awkward, for reasons I try to explain here: https://davmac.wordpress.com/2016/06/18/boost-asio-and-resou...