Hello, I'm endorsing capy after finishing reviewing it for a while, there is concepts such as: - https://github.com/cppalliance/capy/blob/develop/include/boost/capy/concept/... - https://github.com/cppalliance/capy/blob/develop/include/boost/capy/concept/... Which are useful for plenty of I/O use cases such as HTTP, Distributed Systems, Multimedia, HFT, and of course Beast2. I also have a question about the following snippet at: https://github.com/cppalliance/capy/blob/develop/example/asio/use_capy_examp... We can see at line 119: ```cpp capy::run_async(ctx.get_executor())(run_example(client, server)); ``` It's elegant, but maybe we could also benefit from this syntax as well: ```cpp auto& exec{ctx.get_executor()}; exec.run_async(run_example(client, server)); ``` But overall the library is solid, I would 100% recommend it to someone else right now. Thanks, Best, Amlal El Mahrouss amlalelmahrouss@icloud.com