Composition

Every configuration in this repository is assembled the same way:

flake output -> host -> profile -> module -> package or configuration file

ModulesCopy Anchor Link

A module is a Nix function that returns configuration attributes. It is the smallest reusable unit and owns exactly one concern, such as Zsh, Firefox, or PipeWire. Nix merges all imported modules into one final configuration; if two modules set incompatible values, evaluation fails instead of silently picking one.

• modules/nixos/ holds operating-system features. These only work on NixOS.
• modules/home/ holds user features. These work through Home Manager on NixOS, other Linux distributions, and macOS.

A module is either a single name.nix file or a directory whose default.nix is the module and whose other files (often under configs/) are the assets it installs.

ProfilesCopy Anchor Link

A profile is a named bundle of modules for a role. Hosts import profiles rather than long lists of modules, so adding a module to a profile adds it to every machine with that role. See Home profiles and NixOS profiles.

HostsCopy Anchor Link

A host is one machine. Host files stay small: they import profiles and supply the values that cannot be shared, such as the hostname, boot loader, hardware configuration, user account, and setting overrides. Operating-system differences, such as macOS-only packages, are also kept at the host boundary.

UsersCopy Anchor Link

users/ holds settings that belong to one person on every machine. Currently that is the Home Manager stateVersion and enabling Home Manager itself.

Flake outputsCopy Anchor Link

flake.nix turns each host into a named output:

• NixOS hosts become nixosConfigurations.<name> through nixpkgs.lib.nixosSystem, with the Home Manager NixOS module added so the user's environment is built and activated together with the system.
• Standalone Home Manager hosts become homeConfigurations."<user>@<host>" through configLib.mkHome in lib/default.nix. mkHome imports nixpkgs for the target system with unfree packages allowed, applies the NUR overlay and the local overlays, sets the username and home directory, and passes the shared arguments through extraSpecialArgs.

Every module can receive inputs (the flake inputs), configLib (the helper library), and settings (the host's resolved settings) as arguments.

Composition graphsCopy Anchor Link

AsgardCopy Anchor Link

flake.nix
└── hosts/nixos/asgard/
    ├── hardware-configuration.nix
    ├── modules/nixos/secure-boot.nix
    ├── modules/nixos/gaming.nix
    ├── profiles/nixos/desktop.nix
    │   └── modules/nixos/{base,network,archives,nautilus,fonts,gtk,
    │                       multimedia,niri,noctalia,noctalia-greeter,
    │                       1password,pipewire}
    ├── profiles/nixos/development.nix
    │   └── modules/nixos/{docker,jetbrains}
    └── home-manager.users.cbrst
        ├── users/cbrst/home.nix
        ├── profiles/home/development.nix
        ├── profiles/home/desktop-linux.nix
        └── profiles/home/gaming.nix

NiflheimCopy Anchor Link

flake.nix
└── hosts/home/niflheim.nix
    ├── users/cbrst/home.nix
    ├── profiles/home/desktop-macos.nix
    └── profiles/home/development.nix

Where things belongCopy Anchor Link

Hardware details never go into reusable modules, and user preferences never go into hardware modules.