{
  description = "Lgm's NixOS Flake";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    # separate inputs to lock some packages
    # fresh - mostly desktop apps
    nixpkgs-fresh.url = "github:NixOS/nixpkgs/nixos-unstable";
    nixpkgs-stable.url = "github:NixOS/nixpkgs/nixos-23.11";

    flake-parts.url = "github:hercules-ci/flake-parts";
    flake-compat.url = "github:edolstra/flake-compat";
    systems.url = "github:nix-systems/default";
    flake-utils = {
      url = "github:numtide/flake-utils";
      inputs.systems.follows = "systems";
    };

    home-manager = {
      url = "github:nix-community/home-manager/master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    sops-nix = {
      url = "github:Mic92/sops-nix";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.nixpkgs-stable.follows = "nixpkgs-stable";
    };
    mailserver = {
      url = "gitlab:simple-nixos-mailserver/nixos-mailserver/master";
      inputs.flake-compat.follows = "flake-compat";
      inputs.utils.follows = "flake-utils";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    authentik-nix = {
      url = "github:nix-community/authentik-nix";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-parts.follows = "flake-parts";
    };

    nix-cfg-extra.url = "git+https://git.lgmrszd.xyz/lgmrszd/nix-cfg-extra-public.git";
  };

  outputs = inputs@{
    nixpkgs,
    nixpkgs-fresh,
    nixpkgs-stable,
    home-manager,
    sops-nix,
    mailserver,
    authentik-nix,
    ...
  }: 
  let
    system = "x86_64-linux";
    overlay-fresh = final: prev: {
      fresh = import nixpkgs-fresh {
        inherit system;
        config.allowUnfree = true;
      };
    };
    overlay-stable = final: prev: {
      stable = import nixpkgs-stable {
        inherit system;
        config.allowUnfree = true;
      };
    };
    overlay-vaapiIntel = final: prev: {
      vaapiIntel = prev.vaapiIntel.override { enableHybridCodec = true; };
    };
    my-overlays = [
      overlay-fresh
      overlay-stable
      overlay-vaapiIntel
    ];
    inherit (inputs.nix-cfg-extra.lib) extra-data;
  in
  {
    nixosConfigurations.lgm-nixos = nixpkgs.lib.nixosSystem rec {
      inherit system;
      modules = [
        ({ config, pkgs, ... }: { nixpkgs.overlays = my-overlays; })
        ./hosts/laptop/configuration.nix
        ./hosts/laptop/hardware-configuration.nix
        ./hosts/laptop/mounts.nix
        # nix-index-database.nixosModules.nix-index
        sops-nix.nixosModules.sops

        home-manager.nixosModules.home-manager
        {
          home-manager.useGlobalPkgs = true;
          home-manager.useUserPackages = true;
          home-manager.users.lgm = import ./hosts/laptop/home.nix;
        }
      ];
    };
    nixosConfigurations.lgm-vps1 = let
      data = import ./hosts/vps1/data // (if extra-data ? vps1 then extra-data.vps1 else {});
    in
    nixpkgs.lib.nixosSystem rec {
      inherit system;
      specialArgs = { inherit data; };
      modules = [
        ({ config, pkgs, ... }: { nixpkgs.overlays = my-overlays; })
        mailserver.nixosModule
        authentik-nix.nixosModules.default
        ./hosts/vps1/configuration.nix
        ./hosts/vps1/hardware-configuration.nix
        sops-nix.nixosModules.sops
      ];
    };
  };
}