add-feature

name	add-feature
description	Scaffold a new NixOS feature module with enable/disable toggles — self-contained, opt-in system services.
metadata	{"when_to_use":"add feature, new feature module, create feature, add nixos module, scaffold feature"}

Action

1. Create modules/nixosModules/features/<name>.nix:

{
  flake.nixosModules.<name> = { config, lib, pkgs, ... }:
  let cfg = config.<name>; in
  {
    options.<name>.enable = lib.mkEnableOption "Enable <description>";
    config = lib.mkIf cfg.enable { /* service config */ };
  };
}

2. Import in host config: self.nixosModules.<name>
3. Follow import order: External → hardware/disko → base → Nix → security → features → host-specific
4. Guard all config with lib.mkIf cfg.enable

Gotchas

• Filename determines flake.nixosModules.<name> (ssh.nix → self.nixosModules.ssh)
• Importing does NOT enable — host must set <name>.enable = true
• For secrets: import self.nixosModules.sops, declare sops.secrets."..." = {}
• For options consumed by other modules: namespace under options.<name>.port, etc.

Verification

nix eval .#nixosModules.<name> --json 2>&1 | head -3 && grep -r "self.nixosModules.<name>" modules/nixosModules/hosts/