1−-- Run: cabal build -j hackage2nix && time dist/build/hackage2nix/hackage2nix >hackage-packages.nix && mv hackage-packages.nix ~/.nix-defexpr/pkgs/development/haskell-modules/hackage-packages.nix && nix-env -qaP | tail -1
1+-- Run: cabal build -j hackage2nix && time dist/build/hackage2nix/hackage2nix >hackage-packages.nix && mv hackage-packages.nix ~/.nix-defexpr/pkgs/development/haskell-modules/hackage-packages.nix && nix-env -qaP -A haskellngPackages | tail -1