{
  description = "Nixos Config Flake";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.11";
    nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";    
    nix-darwin.url = "github:nix-darwin/nix-darwin/master";
    nix-darwin.inputs.nixpkgs.follows = "nixpkgs-unstable";
    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-25.11";
      inputs.nixpkgs.follows = "nixpkgs";
    };

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

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

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

  outputs = 
    { self, 
      comfyui-nix,
      home-manager,
      home-manager-unstable,
      nix-darwin,
      nix-snapd,
      nixos-hardware, 
      nixpkgs, 
      nixpkgs-unstable,
      nixvim,
      ... 
    }@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" "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" "buildbox" "ender-ml" ] then "server"
          else if hostname == "eva-02" then "macos"
          else "linux-desktop";
      };
    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
        ];
      };

      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
        ];
      };

      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
        ];
      };

      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; }
        ];
      };

      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
        ];
      };

    };
    
    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-unstable.darwinModules.home-manager
        ];
      };
    };
  };
}