{stdenv, fetchurl, static ? false}: stdenv.mkDerivation { name = "zlib-1.2.3"; src = fetchurl { url = http://www.zlib.net/zlib-1.2.3.tar.gz; md5 = "debc62758716a169df9f62e6ab2bc634"; }; configureFlags = if static then "" else "--shared"; # zlib doesn't like the automatic --disable-shared from the Cygwin stdenv. cygwinConfigureEnableShared = true; }