The nix build uses the new flake format to manage dependencies. To add flake support to your native nix setup please see https://nixos.wiki/wiki/Flakes.

The cardano-node nix build depends primarily on haskell.nix and secondarily, for some utilities, on iohk-nix.

Both can be updated with:

nix flake update haskellNix
nix flake update iohkNix

See: https://github.com/input-output-hk/cardano-node-wiki/wiki/building-the-node-using-nix