{
  description = "NixOS flake";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
    unstable.url = "github:nixos/nixpkgs/nixpkgs-unstable";
    nix-snapd.url = "github:nix-community/nix-snapd";
    nix-snapd.inputs.nixpkgs.follows = "nixpkgs";
    spicetify-nix.url = "github:Gerg-L/spicetify-nix";
    autofirma-nix = {
      url = "github:nix-community/autofirma-nix/release-25.05";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    home-manager = {
      url = "github:nix-community/home-manager/release-24.11";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  nixConfig = {
    extra-substituters = [
      "https://nix-community.cachix.org"
    ];
    extra-trusted-public-keys = [
      "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
    ];
  };

  outputs = { self, nixpkgs, unstable, nix-snapd, home-manager, autofirma-nix, ... }:
  let
    system = "x86_64-linux";
    lib = nixpkgs.lib;
    pkgs-unstable = unstable.legacyPackages.${system};
    pkgs = nixpkgs.legacyPackages.${system};
  in
  {
    nixosConfigurations = {
      limgrave = lib.nixosSystem {
        inherit system;
        specialArgs = { inherit pkgs-unstable; };
        modules = [
          ./hosts/limgrave/configuration.nix
          nix-snapd.nixosModules.default
          autofirma-nix.nixosModules.default
          home-manager.nixosModules.home-manager
        ];
      };

      carpates = lib.nixosSystem {
        inherit system;
        specialArgs = { inherit pkgs-unstable; };
        modules = [
          ./hosts/carpates/configuration.nix
          home-manager.nixosModules.home-manager
        ];
      };
    };

    # Home Manager configurations for non-NixOS hosts (e.g., Ubuntu)
    homeConfigurations = {
      # For non-NixOS usage on a machine named "carpates".
      # Run: home-manager switch --flake ./nix#carpates
      carpates = home-manager.lib.homeManagerConfiguration {
        inherit pkgs;
        modules = [ ./hosts/carpates/home.nix ];
      };
    };
  };
}