anchor.diff:  
     setupHook = ./setup-hook-3.0.sh;
   
  +  passthru = {
  +    updateScript = writeScript "update-guile-3" ''
  +      #!/usr/bin/env nix-shell
  +      #!nix-shell -i bash -p curl pcre common-updater-scripts
  +
  +      set -eu -o pipefail
  +
  +      # Expect the text in format of '"https://ftp.gnu.org/gnu/guile/guile-3.0.8.tar.gz"'
  +      new_version="$(curl -s https://www.gnu.org/software/guile/download/ |
  +          pcregrep -o1 '"https://ftp.gnu.org/gnu/guile/guile-(3[.0-9]+).tar.gz"')"
  +      update-source-version ${pname} "$new_version"
  +    '';
  +  };
  +
     meta = with lib; {
       homepage = "https://www.gnu.org/software/guile/";
       description = "Embeddable Scheme implementation";
  
positive.code: , pkg-config
  , pkgsBuildBuild
  , readline
  }:
  
  let
  
negative.code:   ]
    # Disable JIT on Apple Silicon, as it is not yet supported
    # https://debbugs.gnu.org/cgi/bugreport.cgi?bug=44505";
    ++ lib.optional (stdenv.isDarwin && stdenv.isAarch64) "--enable-jit=no"
    # At least on x86_64-darwin '-flto' autodetection is not correct:
    #  https://github.com/NixOS/nixpkgs/pull/160051#issuecomment-1046193028
    ++ lib.optional (stdenv.isDarwin) "--disable-lto";
  
    postInstall = ''
      wrapProgram $out/bin/guile-snarf --prefix PATH : "${gawk}/bin"
  