Comment by djs55

Are you trying to avoid linking against Cygwin at runtime or trying to avoid Cygwin in the build environment too? In my case I use Cygwin in the build environment (see https://github.com/moby/vpnkit/blob/master/appveyor.yml) using Andreas Hauptmann's https://github.com/fdopen/opam-repository-mingw but I end up with an executable which doesn't require the Cygwin dll at runtime.

I'm looking forward to the day when I won't need Cygwin even in the build environment. Since the OCaml compiler itself works fine on Windows and modern build systems like "dune" are also Windows-friendly I'm fairly optimistic this can happen soon. I think it'll mostly be a matter of removing accidental Unix-isms (like unnecessary use of symlinks) in the build scripts.