{
  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";

  outputs = { self, nixpkgs }:
  let
    pkgs = import nixpkgs {
      system = "x86_64-linux";
    };
  in {
    packages.x86_64-linux.pigeon-kernel = pkgs.callPackage ./kernel/kernel.nix { };
    packages.x86_64-linux.pigeon-rootfs = pkgs.callPackage ./rootfs/rootfs.nix {
      pigeon-toolchain = with pkgs; [ bash coreutils gcc gnumake util-linux ];
    };
  };
}