anchor.diff:  { lib
   , stdenv
   , fetchFromGitHub
  -, fetchpatch
   , meson
   , ninja
   , pkg-config
  
positive.code:     inherit (src.meta) homepage;
      license = licenses.mit;
      platforms = platforms.linux;
      maintainers = with maintainers; [ gnxlxnxx ];
    };
  }
  
negative.code: 
  stdenv.mkDerivation rec {
    pname = "swaylock-effects";
    version = "unstable-2021-10-21";
  
    src = fetchFromGitHub {
      owner = "mortie";
      repo = "swaylock-effects";
      rev = "a8fc557b86e70f2f7a30ca9ff9b3124f89e7f204";
      sha256 = "sha256-GN+cxzC11Dk1nN9wVWIyv+rCrg4yaHnCePRYS1c4JTk=";
    };
  
    postPatch = ''
      sed -iE "s/version: '1\.3',/version: '${version}',/" meson.build
  