{
  description = "personal NixOS configurations";

  inputs = {
    # Nixpkgs, NixOS's official repo
    nixpkgs.url = "github:nixos/nixpkgs/release-21.11";

    # We use the unstable nixpkgs repo for some packages.
    nixpkgs-unstable.url = "github:nixos/nixpkgs/nixpkgs-unstable";

    home-manager = {
      url = "github:nix-community/home-manager/release-21.11";
      # We want home-manager to use the same set of nixpkgs as our system.
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  # Output config, or config for NixOS system
  outputs = { self, nixpkgs, home-manager, ... }@inputs: {
    nixosConfigurations = {
      # desktop
      carmel = nixpkgs.lib.nixosSystem {
        system = "x86_64-linux";
        modules = [
          ./hosts/carmel/configuration.nix
          ./users/fcuny
          ./modules/systems
          ./modules/desktop
        ];
      };
    };
  };
}