anchor.diff:    };
   
     libwebsockets_4_3 = generic {
  -    version = "4.3.0";
  -    sha256 = "13lxb487mqlzbsbv6fbj50r1717mfwdy87ps592lgfy3307yqpr4";
  +    version = "4.3.1";
  +    sha256 = "sha256-lB3JHh058cQc5rycLnHk3JAOgtku0nRCixN5U6lPKq8=";
  +    patches = [
  +      # fixes the propagated cmake files, fixing the build of ttyd
  +      # see also https://github.com/tsl0922/ttyd/issues/918
  +      (fetchpatch {
  +        url = "https://github.com/warmcat/libwebsockets/commit/99a8b9c4422bed45c8b7412a1e121056f2a6132a.patch";
  +        hash = "sha256-zHBo2ZEayvibM+jzeVaZqySxghaOLUglpSFwuGhl6HM=";
  +      })
  +    ];
     };
   }
  
positive.code:       rev = "v${version}";
        inherit sha256;
      };
  
      buildInputs = [ openssl zlib libuv ];
  
  
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;
  
  