anchor.diff:    src = fetchurl {
       url = "https://github.com/fish-shell/fish-shell/releases/download/${version}/${name}.tar.gz";
       hashOutput = false;
  -    sha256 = "7ee5bbd671c73e5323778982109241685d58a836e52013e18ee5d9f2e638fdfb";
  +    sha256 = "e42bb19c7586356905a58578190be792df960fa81de35effb1ca5a5a981f0c5a";
     };
   
     nativeBuildInputs = [
  
positive.code: }:
  
  let
    version = "2.6.0";
  in
  stdenv.mkDerivation rec {
    name = "fish-${version}";
  
negative.code:   ];
  
    configureFlags = [
      "--without-included-pcre2"
    ];
  
  