Using node2nix without generating an explicit `node-packages.nix`

[lenianiva]

Is there a way to use node2nix in a flake like crate2nix? In crate2nix, the intermediate Cargo.nix file does not have to be checked into the repo but instead can be generated on the fly: https://github.com/nix-community/crate2nix/blob/236f6addfd452a48be805819e3216af79e988fd5/tools.nix#L28.