anchor.diff:  with stdenv.lib;
   
   stdenv.mkDerivation rec {
  -  version = "0.25.2";
  +  version = "0.25.3";
     name = "notmuch-${version}";
   
     passthru = {
  
positive.code:   ++ optionals (!stdenv.isDarwin) [ gdb man ]; # test dependencies
  
    postPatch = ''
      find test -type f -exec \
        sed -i \
          -e "1s|#!/usr/bin/env bash|#!${bash}/bin/bash|" \
          -e "s|gpg |${gnupg}/bin/gpg |" \
          -e "s| gpg| ${gnupg}/bin/gpg|" \
          -e "s|gpgsm |${gnupg}/bin/gpgsm |" \
          -e "s| gpgsm| ${gnupg}/bin/gpgsm|" \
          -e "s|crypto.gpg_path=gpg|crypto.gpg_path=${gnupg}/bin/gpg|" \
          "{}" ";"
  
      for src in \
  
negative.code: 
    src = fetchurl {
      url = "http://notmuchmail.org/releases/${name}.tar.gz";
      sha256 = "1fyx20rjpwbf2j1v5fpa5s0rjnwhcgvijzh2qyinp8rlbh1qxmab";
    };
  
    nativeBuildInputs = [ pkgconfig ];
  