Batteries Reference

import { Aside } from ‘@astrojs/starlight/components’;

Source: [`modules/aspects/provides/`](https://github.com/vic/den/tree/main/modules/aspects/provides)

Overview

Batteries are pre-built aspects at den.provides (accessed via den._.<name>). All are opt-in — include them explicitly where needed.

define-user

Defines a user at OS and Home-Manager levels. (source)

den.default.includes = [ den._.define-user ];

Sets:

• users.users.<name>.{name, home, isNormalUser} (NixOS)
• users.users.<name>.{name, home} (Darwin)
• home.{username, homeDirectory} (Home-Manager)

Contexts: { host, user }, { home }

primary-user

Makes a user an administrator. (source)

den.aspects.vic.includes = [ den._.primary-user ];

Sets:

• NixOS: users.users.<name>.extraGroups = [ "wheel" "networkmanager" ]
• Darwin: system.primaryUser = <name>
• WSL: wsl.defaultUser = <name> (if host has wsl attribute)

Context: { host, user }

user-shell

Sets default shell at OS and HM levels. (source)

den.aspects.vic.includes = [ (den._.user-shell "fish") ];

Sets:

• programs.<shell>.enable = true (NixOS/Darwin)
• users.users.<name>.shell = pkgs.<shell> (NixOS/Darwin)
• programs.<shell>.enable = true (Home-Manager)

Contexts: { host, user }, { home }

unfree

Enables unfree packages by name. (source · predicate)

den.aspects.laptop.includes = [ (den._.unfree [ "discord" ]) ];

Sets: unfree.packages option + nixpkgs.config.allowUnfreePredicate

Contexts: All (host, user, home) — works for any class.

useGlobalPkgs interaction

When Home-Manager’s useGlobalPkgs is true, the unfree module skips setting nixpkgs.config on the HM class to avoid conflicts. Set unfree packages on the host aspect instead.

tty-autologin

Automatic tty login.

den.aspects.laptop.includes = [ (den._.tty-autologin "root") ];

Sets: systemd.services."getty@tty1" with autologin.

Class: NixOS only.

import-tree

Auto-imports non-dendritic Nix files by class directory. (source)

den.aspects.laptop.includes = [ (den._.import-tree ./path) ];

Looks for ./path/_nixos/, ./path/_darwin/, ./path/_homeManager/.

Helpers:

den._.import-tree._.host ./hosts   # per host: ./hosts/<name>/_<class>
den._.import-tree._.user ./users   # per user: ./users/<name>/_<class>
den._.import-tree._.home ./homes   # per home: ./homes/<name>/_<class>

Requires: inputs.import-tree

inputs’ (flake-parts)

Provides per-system inputs' as a module argument.

den.default.includes = [ den._.inputs' ];

Requires: flake-parts with withSystem.

self’ (flake-parts)

Provides per-system self' as a module argument.

den.default.includes = [ den._.self' ];

Requires: flake-parts with withSystem.

forward

Creates custom Nix classes by forwarding configs between classes. (source · usage guide)

den._.forward {
  each = lib.singleton class;
  fromClass = _: "source";
  intoClass = _: "nixos";
  intoPath = _: [ "target" "path" ];
  fromAspect = _: sourceAspect;
}

Returns an aspect. Used internally for Home-Manager integration.

home-manager

HM integration is handled by den.ctx.hm-host and den.ctx.hm-user context types, which are activated automatically when hosts have HM users.

All homeManager class settings are forwarded to os-level home-manager.users.<userName>.

user

The user class is automatically handled by Den and forwards to os-level users.users.<userName>

You can write:

den.aspects.tux.user.description = "bird";

# same as setting at host:
den.aspects.igloo.nixos.users.users.tux.description = "bird";