Fibers work on macOS is being done here.
https://github.com/wingo/fibers/pull/42

This is now working with both web servers.

On Wed, Jul 29, 2020 at 5:06 PM Aleix Conchillo Flaqué <aconchillo@gmail.com>
wrote:

> SOCK_NONBLOCK was not implemented when accept4() is not available (e.g.
> macOS).
>
> I'm currently testing all this with the two new web server implementations
> provided with Fibers.
>
> Aleix
>