{
  description = "Declarative NixOS HomeLab";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs";
    # systems.url = "github:nix-systems/default";
    sops-nix = {
      url = "github:Mic92/sops-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    simple-nixos-mailserver = {
      url = "gitlab:simple-nixos-mailserver/nixos-mailserver";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    # home-manager = {
    #   url = "home-manager";
    #   inputs.nixpkgs.follows = "nixpkgs";
    # };
    colmena.url = "github:zhaofengli/colmena";
  };

  outputs = {
    self,
    nixpkgs,
    # systems,
    sops-nix,
    # home-manager,
    colmena,
    simple-nixos-mailserver,
    ...
  } @ inputs: let
    overlays = [
      colmena.overlays.default
    ];
  in {
    colmenaHive = colmena.lib.makeHive self.outputs.colmena;
    colmena = (import ./hive.nix) (inputs // {inherit overlays;});
  };
}