pkgGroup.nix

{ tryEval, pkgConfig, callPackage, fetchgitPrivate }:
let src     = <path>;
    lib1 = callPackage ./lib1.nix { inherit src; };
    lib2 = callPackage ./lib2.nix { inherit src; };
    lib3 = callPackage ./lib3.nix { inherit src;
                                    inherit lib1;
                                    inherit lib2; };
   lib4 = callPackage ./lib4.nix { inherit src;
                                   inherit lib3;
                                   inherit lib1; };
   bin1 = callPackage ./lib5.nix { inherit src;
                                   inherit lib3;
                                   inherit lib1; };
   bin2 = callPackage ./bin1.nix { inherit src;
                                   inherit lib4;
                                   inherit lib3;
                                   inherit lib1;
                                   inherit lib2; };
in { inherit lib3 lib1 lib2 bin1 bin2 lib4;
     grpPackages = { inherit lib1 lib2 lib3 bin1 bin2; };
  }