anchor.diff:        substituteInPlace tests/testsuite.at --replace \
           'm4_include([dbmfetch03.at])' ""
     '';
  +
  +  enableParallelBuilding = true;
     configureFlags = [ "--enable-libgdbm-compat" ];
   
  +  # create symlinks for compatibility
     postInstall = ''
  -    # create symlinks for compatibility
       install -dm755 $out/include/gdbm
       (
         cd $out/include/gdbm
  
positive.code: { stdenv, lib, fetchurl }:
  
  stdenv.mkDerivation rec {
    name = "gdbm-1.18.1";
    # FIXME: remove on update to > 1.18.1
    NIX_CFLAGS_COMPILE = if stdenv.cc.isClang then "-Wno-error=return-type" else null;
  
    src = fetchurl {
      url = "mirror://gnu/gdbm/${name}.tar.gz";
      sha256 = "1p4ibds6z3ccy65lkmd6lm7js0kwifvl53r0fd759fjxgr917rl6";
    };
  
  
negative.code: 
    meta = with lib; {
      description = "GNU dbm key/value database library";
      longDescription = ''
         GNU dbm (or GDBM, for short) is a library of database functions that
         use extensible hashing and work similar to the standard UNIX dbm.
         These routines are provided to a programmer needing to create and
         manipulate a hashed database.
  
         The basic use of GDBM is to store key/data pairs in a data file.
         Each key must be unique and each key is paired with only one data
         item.
  
         The library provides primitives for storing key/data pairs,
         searching and retrieving the data by its key and deleting a key
         along with its data.  It also support sequential iteration over all
         key/data pairs in a database.
  
         For compatibility with programs using old UNIX dbm function, the
         package also provides traditional dbm and ndbm interfaces.
        '';
      homepage = https://www.gnu.org/software/gdbm/;
      license = licenses.gpl3Plus;
      platforms = platforms.all;
  