Users¶

How users are defined, where their config lives, and how to add a new one.

Where user identity lives¶

All user identities are defined in config.nix at the repo root:

{
  users = {
    me = {
      username = "niksingh710";
      fullname = "Nikhil Singh";
      email = "nikhil@semi.sh";
      sshPublicKeys = [ "ssh-ed25519 AAAA... nikhil@semi.sh" ];
    };
    jp = {
      username = "nikhil.singh";
      fullname = "Nikhil Singh";
      email = "nikhil.singh@juspay.in";
      sshPublicKeys = [ "ssh-ed25519 AAAA... nikhil.singh@juspay.in" ];
    };
    # per-host overrides (obox, bbox use "nikhil" as username)
  };
}

This is the single source of truth for usernames, full names, emails, and SSH keys. Host configs import it as cfg = import (flake + "/config.nix").

Where user system config lives¶

NixOS users are created in the common host configs, not in users/ files:

Host type	Where the user is created	File
Workstation (dsd, semi)	`common/workstation.nix`	`users.users.nikhil.singh = { isNormalUser = true; ... }`
Cloud server (obox, bbox)	`common/cloud.nix`	`users.users.${username} = { isNormalUser = true; ... }`
Standalone (mach)	Host `default.nix` directly	User created inline

The hosts/nixos/<host>/users/ directory is for home-manager config only - what the user's home environment looks like (shell, editor, packages, AI tools). It does NOT create the system user.

Where home-manager config lives¶

Each host has a users/ directory with one .nix file per user:

hosts/nixos/dsd/users/nikhil.singh.nix    # home-manager for nikhil.singh on dsd
hosts/nixos/mach/users/niksingh710.nix    # home-manager for niksingh710 on mach
hosts/nixos/obox/users/nikhil.nix         # home-manager for nikhil on obox
hosts/darwin/jp-mbp/users/nikhil.singh.nix

These files import home modules (flake.homeModules.ai, flake.homeModules.shell, etc.) and set per-host overrides (git identity, syncthing creds, nvix variant, etc.).

nix-wire auto-imports these files - drop a .nix in users/ and it's wired automatically. No import list to maintain.

Adding a new user¶

1. Add identity to config.nix¶

users = {
  me = { ... };
  jp = { ... };
  newuser = {
    username = "newuser";
    fullname = "New User";
    email = "newuser@example.com";
    sshPublicKeys = [ "ssh-ed25519 AAAA... newuser@example.com" ];
  };
};

2. Create the system user¶

In the host's common config (or default.nix for standalone hosts):

users.users.newuser = {
  isNormalUser = true;
  extraGroups = [ "wheel" "networkmanager" ];
  openssh.authorizedKeys.keys = cfg.users.newuser.sshPublicKeys;
};

For extra SSH-only users (no home-manager), see hosts/nixos/dsd/extra-users.nix for a pattern that creates users from a key map.

3. Add home-manager config (if needed)¶

Create hosts/nixos/<host>/users/newuser.nix:

{ flake, ... }:
{
  imports = [
    flake.homeModules.shell
    flake.homeModules.editor
  ];
}

nix-wire auto-imports it. The hm alias (config.hm.*) is wired in the common configs:

# In common/workstation.nix or common/cloud.nix:
(lib.mkAliasOptionModule [ "hm" ] [ "home-manager" "users" me.username ])

If the username differs from the default, add the alias for that user too.

Standalone home-manager (non-NixOS)¶

For machines not managed by this flake's NixOS configs:

hosts/home/nikhil.nix    # standalone home-manager for nikhil
hosts/home/admin.nix     # standalone home-manager for admin

These compose homeModules.default + homeModules.home-only.