{
  description = "Nixos Config Flake";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-26.05";
    nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
    nix-darwin.url = "github:nix-darwin/nix-darwin/nix-darwin-26.05";
    nix-darwin.inputs.nixpkgs.follows = "nixpkgs";
    nix-snapd.url = "github:nix-community/nix-snapd";
    comfyui-nix.url = "github:utensils/comfyui-nix";
    #nix-snapd.inputs.pkgs-unstable.follows = "nixpkgs";

    home-manager = {
      url = "github:nix-community/home-manager/release-26.05";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    home-manager-unstable = {
      url = "github:nix-community/home-manager/master";
      inputs.nixpkgs.follows = "nixpkgs-unstable";
    };

    nixvim = {
      url = "github:nix-community/nixvim/nixos-26.05";
    };

    nixos-hardware = {
      url = "github:NixOS/nixos-hardware/master";
      #inputs.nixpkgs.follows = "nixpkgs";
    };

    disko = {
      url = "github:nix-community/disko";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = {
    self,
    comfyui-nix,
    home-manager,
    home-manager-unstable,
    nix-darwin,
    nix-snapd,
    nixos-hardware,
    nixpkgs,
    nixpkgs-unstable,
    nixvim,
    disko,
    ...
  } @ inputs: let
    system = "x86_64-linux";
    configPath = "/etc/nixos";
    pkgs-unstable = import nixpkgs-unstable {
      system = system;
      config.allowUnfree = true;
      overlays = [comfyui-nix.overlays.default];
    };

    # Host type abstractions
    hostTypes = {
      # Server hosts
      isServer = hostname: builtins.elem hostname ["acheron" "armaros" "buildbox" "ender-ml"];

      # Linux desktop hosts
      isLinuxDesktop = hostname: builtins.elem hostname ["eva-01" "eva-03"];

      # macOS host
      isMacos = hostname: hostname == "eva-02";

      # Helper to get host type category
      getHostType = hostname:
        if builtins.elem hostname ["acheron" "armaros" "buildbox" "ender-ml"]
        then "server"
        else if hostname == "eva-02"
        then "macos"
        else "linux-desktop";
    };

    # Hosts that have rescue/installer ISOs
    isoHosts = ["acheron" "armaros" "buildbox" "ender-ml" "eva-01" "eva-03"];

    # Build a rescue/installer ISO configuration for a host
    mkIso = hostname: {
      specialArgs = {
        inherit inputs configPath hostTypes;
        pkgs-unstable = import nixpkgs-unstable {
          inherit system;
          config.allowUnfree = true;
        };
        hostname = "${hostname}-iso";
      };
      inherit system;
      modules = [
        "${nixpkgs}/nixos/modules/installer/cd-dvd/installation-cd-minimal.nix"
        ./hosts/${hostname}/iso.nix
        inputs.disko.nixosModules.disko
      ];
    };

    # ── DevShell Helpers ─────────────────────────────────────────
    supportedSystems = ["x86_64-linux" "aarch64-darwin"];
    forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
  in {
    nixosConfigurations =
      {
        acheron = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "acheron";
          };
          system = system;
          modules = [
            ./hosts/acheron/configuration.nix
            inputs.home-manager.nixosModules.default
            inputs.disko.nixosModules.disko
          ];
        };

        armaros = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "armaros";
          };
          system = system;
          modules = [
            ./hosts/armaros/configuration.nix
            inputs.home-manager.nixosModules.default
            inputs.disko.nixosModules.disko
          ];
        };

        buildbox = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "buildbox";
          };
          system = system;
          modules = [
            ./hosts/buildbox/configuration.nix
            inputs.home-manager.nixosModules.default
            inputs.disko.nixosModules.disko
          ];
        };

        ender-ml = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "ender-ml";
          };
          system = system;
          modules = [
            ./hosts/ender-ml/configuration.nix
            inputs.home-manager.nixosModules.default
            comfyui-nix.nixosModules.default
            inputs.disko.nixosModules.disko
          ];
        };

        eva-01 = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "eva-01";
          };
          system = system;
          modules = [
            ./hosts/eva-01/configuration.nix
            inputs.home-manager.nixosModules.default
            nixos-hardware.nixosModules.lenovo-thinkpad-x1-nano-gen1
            nix-snapd.nixosModules.default
            {services.snap.enable = true;}
            inputs.disko.nixosModules.disko
          ];
        };

        eva-03 = nixpkgs.lib.nixosSystem {
          specialArgs = {
            inherit inputs pkgs-unstable configPath hostTypes;
            hostname = "eva-03";
          };
          system = system;
          modules = [
            ./hosts/eva-03/configuration.nix
            inputs.home-manager.nixosModules.default
            comfyui-nix.nixosModules.default
            inputs.disko.nixosModules.disko
          ];
        };
      }
      # ── Rescue / installer ISOs (generated) ──────────────────────
      // builtins.listToAttrs (map (name: {
          name = "${name}-iso";
          value = nixpkgs.lib.nixosSystem (mkIso name);
        })
        isoHosts);

    darwinConfigurations = {
      eva-02 = nix-darwin.lib.darwinSystem {
        specialArgs = {
          inherit inputs configPath hostTypes;
          hostname = "eva-02";
          pkgs-unstable = import nixpkgs-unstable {
            system = "aarch64-darwin";
            config.allowUnfree = true;
            overlays = [comfyui-nix.overlays.default];
          };
        };
        system = "aarch64-darwin";
        modules = [
          ./hosts/eva-02/configuration.nix
          inputs.home-manager.darwinModules.home-manager
        ];
      };
    };

    # ── Dev Shells (for direnv) ──────────────────────────────────
    devShells = forAllSystems (sys: let
      pkgs = nixpkgs.legacyPackages.${sys};
    in {
      # Notice the 'default =' here!
      default = pkgs.mkShell {
        buildInputs = with pkgs; [
          nixd
          alejandra
          git
          nil
          bun
          xorriso
        ];
      };
    });
  };
}