anchor.diff:  
     buildInputs = [
       cmocka
  +    lmdb
       talloc
       tdb
       tevent
  
positive.code:   src = fetchurl {
      urls = map (n: "${n}.gz") tarballUrls;
      hashOutput = false;
      sha256 = "2b3070f6127d9684e928038abad441e18aef8c2ce703c3ec5d57fadd4ecdfa91";
    };
  
    nativeBuildInputs = [
  
negative.code: }:
  
  let
    name = "ldb-1.4.0";
  
    tarballUrls = [
      "mirror://samba/ldb/${name}.tar"
  