anchor.diff: -{ lib, stdenv, fetchzip, cmake, zlib }:
  +{ lib
  +, stdenv
  +, fetchzip
  +, cmake
  +, zlib
  +}:
   
   stdenv.mkDerivation rec {
     pname = "zdbsp";
  
positive.code: 
    src = fetchzip {
      url = "https://zdoom.org/files/utils/zdbsp/zdbsp-${version}-src.zip";
      sha256 = "1j6k0appgjjj3ffbll9hy9nnbqr17szd1s66q08zrbkfqf6g8f0d";
      stripRoot = false;
    };
  
  
negative.code:   '';
  
    meta = with lib; {
      homepage = "https://zdoom.org/wiki/ZDBSP";
      description = "ZDoom's internal node builder for DOOM maps";
      license = licenses.gpl2Plus;
      maintainers = with maintainers; [ lassulus siraben ];
      platforms = platforms.unix;
  