anchor.diff:      ++ lib.optional enableDMARC opendmarc
       ++ lib.optional enableRedis hiredis;
   
  -  preBuild = ''
  +  configurePhase = ''
  +    runHook preConfigure
  +
       sed '
         s:^\(BIN_DIRECTORY\)=.*:\1='"$out"'/bin:
         s:^\(CONFIGURE_FILE\)=.*:\1=/etc/exim.conf:
  
positive.code:     hash = "sha256-KZpWknsus0d9qv08W9oCvGflxOWJinrq8nQIdSeM8aM=";
    };
  
    nativeBuildInputs = [ pkg-config ];
    buildInputs = [ coreutils db openssl perl pcre2 ]
      ++ lib.optional enableLDAP openldap
  
negative.code:       for i in mailq newaliases rmail rsmtp runq sendmail; do
          ln -s exim $i
        done )
  
      runHook postInstall
    '';
  
    meta = with lib; {
  