{
  description = "GKleen's flakey nixos configuration";

  inputs = {
    nixpkgs = {
      type = "github";
      owner = "NixOS";
      repo = "nixpkgs";
      ref = "master";
    };
    home-manager = {
      type = "github";
      owner = "nix-community";
      repo = "home-manager";
      ref = "master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    sops-nix = {
      type = "github";
      owner = "Mic92";
      repo = "sops-nix";
      ref = "master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    deploy-rs = {
      type = "github";
      owner = "serokell";
      repo = "deploy-rs";
      ref = "master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    nvfetcher = {
      type = "github";
      owner = "berberman";
      repo = "nvfetcher";
      ref = "master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    flake-compat = {
      type = "github";
      owner = "edolstra";
      repo = "flake-compat";
      ref = "master";
      flake = false;
    };
  };

  outputs = { self, nixpkgs, home-manager, sops-nix, deploy-rs, nvfetcher, ... }@inputs:
    let
      inherit (builtins) attrNames attrValues elemAt toJSON isNull pathExists;
      inherit (nixpkgs) lib;
      utils = import ./utils { inherit lib; };
      inherit (utils) nixImport overrideModule;
      inherit (lib) nixosSystem mkIf splitString filterAttrs listToAttrs mapAttrsToList nameValuePair concatMap composeManyExtensions mapAttrs mapAttrs' recursiveUpdate genAttrs unique elem optionalAttrs isDerivation concatLists concatStringsSep;
      inherit (lib.strings) escapeNixString;

      accountUserName = accountName: 
        let
          accountName' = splitString "@" accountName;
        in elemAt accountName' 0;
      accountHostName = accountName: 
        let
          accountName' = splitString "@" accountName;
        in elemAt accountName' 1;

      mkSources = pkgs: optionalAttrs (pathExists _sources/generated.nix) { sources = pkgs.callPackage _sources/generated.nix {}; };

      mkOverlay = path: final: prev: import path ({ inherit final; inherit prev; } // mkSources prev);

      mkNixosConfiguration = addProfiles: dir: path: hostName: nixosSystem rec {
        specialArgs = {
          flake = self;
          flakeInputs = inputs;
          path = ./.;
        };
        modules =
          let
            defaultProfiles = with self.nixosModules.systemProfiles;
              [ core
              ];

            local = dir + "/${path}";
            argsModule = { pkgs, ... }: {
              _module.args = {
                customUtils = utils;
                inherit hostName;
              } // mkSources pkgs;
            };
            accountModules = attrValues (filterAttrs accountMatchesHost self.nixosModules.accounts);
            accountMatchesHost = n: _v: accountHostName n == hostName;
          in attrValues (filterAttrs (n: _v: !(elem n ["systemProfiles" "users" "userProfiles" "accounts"])) self.nixosModules) ++ [ argsModule ] ++ defaultProfiles ++ addProfiles ++ [ local ] ++ accountModules;
      };

      mkSystemProfile = dir: path: profileName: {
        imports = [ (dir + "/${path}") ];
        config = {
          system.profiles = [profileName];
        };
      };

      defaultUserProfiles = userName: with self.nixosModules.userProfiles.${userName};
        [ core
        ];

      mkUserModule = dir: path: userName:
        overrideModule (import (dir + "/${path}"))
                       (inputs: inputs // { inherit userName; })
                       (outputs: { _file = dir + "/${path}"; }
                              // outputs
                              // { imports = defaultUserProfiles userName ++ (outputs.imports or []); });
      
      mkUserProfile = userName: dir: path: profileName:
        let
          profileModule = overrideModule (import (dir + "/${path}"))
                                         (inputs: inputs // { inherit userName; })
                                         (outputs: { _file = dir + "/${path}"; }
                                                // outputs);
        in {
          imports = [profileModule];
          config = {
            users.users.${userName}.profiles = [profileName];
          };
        };

      mkAccountModule = dir: path: accountName:
        let
          userName = accountUserName accountName;
        in overrideModule
             (import (dir + "/${path}"))
             (inputs: inputs // { inherit userName; })
             (outputs: { _file = dir + "/${path}"; }
                      // outputs
                      // { imports = [self.nixosModules.users.${userName} or ({...}: { imports = defaultUserProfiles userName; })] ++ (outputs.imports or []); });

      systemsSelector = "x86_64-linux";
      forAllSystems = f: mapAttrs f (filterAttrs (system: _systemPkgs: !(isNull (builtins.match systemsSelector system))) nixpkgs.legacyPackages);
      forAllUsers = genAttrs (unique (map accountUserName (attrNames self.nixosModules.accounts)));

      activateNixosConfigurations = forAllSystems (system: _pkgs: mapAttrs' (hostName: nixosConfig: nameValuePair "${hostName}-activate" { type = "app"; program = "${nixosConfig.config.system.build.toplevel}/bin/switch-to-configuration"; }) self.nixosConfigurations);

      overlayPaths = nixImport rec { dir = ./overlays; _import = (path: _name: dir + "/${path}"); };

      installerProfiles = system:
        let nixpkgs-path = nixpkgs.legacyPackages.${system}.path;
        in mapAttrs (name: {path, output}: { profile = mkSystemProfile nixpkgs-path path "installer-${name}"; inherit output; })
          { cd-dvd = { path = "nixos/modules/installer/cd-dvd/installation-cd-minimal.nix"; output = out: out.config.system.build.isoImage; };
            netboot = { path = "nixos/modules/installer/netboot/netboot-minimal.nix"; output = out: (self.legacyPackages.${system}.symlinkJoin { name = "netboot"; paths = with out.config.system.build; [ netbootRamdisk kernel netbootIpxeScript ]; preferLocalBuild = true; }); };
          };

      installerConfig = if pathExists ./installer.nix then "installer.nix" else (if pathExists ./installer then "installer" else null);
      installers =
        let mkInstallers = system: mapAttrs (mkInstaller system) (installerProfiles system);
            mkInstaller = system: name: {profile, output}: let mkOutput = output; in rec { config = mkNixosConfiguration [profile { config = { nixpkgs.system = system; }; }] ./. installerConfig "installer"; output = mkOutput config; };
        in forAllSystems (system: _systemPkgs: optionalAttrs (!(isNull installerConfig)) (mkInstallers system));
      installerNixosConfigurations = listToAttrs (concatLists (mapAttrsToList (system: mapAttrsToList (profile: { config, ... }: nameValuePair ("installer-${system}-${profile}") config)) installers));

      packages = forAllSystems (system: systemPkgs: composeManyExtensions (attrValues self.overlays) self.legacyPackages.${system} systemPkgs);

      activateHomeManager = system: base: (deploy-rs.lib.${system}.activate.custom // { dryActivate = "DRY_RUN=1 $PROFILE/activate"; }) base.activationPackage "$PROFILE/activate";
    in
      {
        nixosModules =
          let modulesAttrs = nixImport { dir = ./modules; };
              systemProfiles = nixImport rec { dir = ./system-profiles; _import = mkSystemProfile dir; };
              users = nixImport rec { dir = ./users; _import = mkUserModule dir; };
              userProfiles = forAllUsers (userName: nixImport rec { dir = ./user-profiles; _import = mkUserProfile userName dir; });
              accounts = recursiveUpdate rootAccounts (nixImport rec { dir = ./accounts; _import = mkAccountModule dir; });
              rootAccounts = mapAttrs' (hostName: _value: nameValuePair "root@${hostName}" ({...}: { imports = [ self.nixosModules.users.root or ({...}: { imports = defaultUserProfiles "root"; }) ]; })) self.nixosConfigurations;
          in modulesAttrs // { inherit systemProfiles users userProfiles accounts; };
        nixosConfigurations = installerNixosConfigurations // nixImport rec { dir = ./hosts; _import = mkNixosConfiguration [] dir; };

        homeModules = nixImport rec { dir = ./home-modules; };
        homeConfigurations = listToAttrs (concatLists (mapAttrsToList (hostname: nixosConfig: mapAttrsToList (username: configuration: nameValuePair "${username}@${hostname}" { inherit (configuration.home) activationPackage; }) nixosConfig.config.home-manager.users) self.nixosConfigurations));

        overlays = mapAttrs (_name: path: mkOverlay path) overlayPaths;

        packages = mapAttrs (_name: filterAttrs (_name: isDerivation)) packages;
        packages' = mapAttrs (_name: filterAttrs (_name: value: !(isDerivation value))) packages;

        legacyPackages = forAllSystems (system: systemPkgs: recursiveUpdate systemPkgs packages.${system});

        apps = activateNixosConfigurations;

        devShells = forAllSystems (system: systemPkgs: { default = import ./shell.nix {
          pkgs = self.legacyPackages.${system};
          deploy-rs = deploy-rs.packages.${system}.deploy-rs;
          nvfetcher = nvfetcher.defaultPackage.${system};
        };});

        templates.default = {
          path = ./.;
          description = "GKleen's flakey nixos configuration";
        };

        deploy.nodes = let
          defaults = mapAttrs (hostname: _: {
            inherit hostname;
            sshUser = "root";

            profilesOrder = ["system"]; # system first
            profiles = {
              system = {
                path = deploy-rs.lib.${self.nixosConfigurations.${hostname}.config.nixpkgs.system}.activate.nixos self.nixosConfigurations.${hostname};
              };
            } // (mapAttrs (_user: usercfg: {
              user = usercfg.home.username;
              path = activateHomeManager (self.nixosConfigurations.${hostname}.config.nixpkgs.system) usercfg.home;
            }) self.nixosConfigurations.${hostname}.config.home-manager.users);
          }) (nixImport { dir = ./hosts; _import = (_path: name: name); });
          overrides = if pathExists ./deploy then nixImport { dir = ./deploy; _import = path: _name: import (./deploy + "/${path}") inputs; } else {};
          filterEnabled = attrs: mapAttrs (_n: v: filterAttrs (n: _v: n != "enabled") v) (filterAttrs (_n: v: v.enabled or true) attrs);
        in mapAttrs (_n: v: if v ? "profiles" then v // { profiles = filterEnabled v.profiles; } else v) (filterEnabled (recursiveUpdate defaults overrides));

        checks = builtins.mapAttrs (system: deployLib: deployLib.deployChecks self.deploy) deploy-rs.lib;
      };
}