anchor.diff:        rev = "v${version}";
         inherit sha256;
       };
  +
  +    inherit patches;
   
       buildInputs = [ openssl zlib libuv ];
   
  
positive.code:   };
  
    libwebsockets_4_3 = generic {
      version = "4.3.0";
      sha256 = "13lxb487mqlzbsbv6fbj50r1717mfwdy87ps592lgfy3307yqpr4";
    };
  }
  
negative.code: , openssl
  , zlib
  , libuv
  , fetchpatch
  # External poll is required for e.g. mosquitto, but discouraged by the maintainer.
  , withExternalPoll ? false
  }:
  
  let
    generic = { version, sha256, patches ? [] }: stdenv.mkDerivation rec {
      pname = "libwebsockets";
      inherit version;
  
  