This repository contains a multi-host, multi-user Darwin system configuration using Nix flakes. It leverages nix-darwin and home-manager to manage macOS configurations declaratively.

Description

The flake configuration is designed to support multiple hosts and users with specific configurations for each. It uses let-bindings and strict commas for better readability and maintainability.

Structure

Host Variables: Define host-specific settings such as hostname, architecture, and home directory.
User Variables: Define user-specific settings such as username, home directory, and shell.
Base Darwin Config Function: A reusable function to set up base configurations for each host.
Host Configurations: Specific configurations for each host, including nix-darwin and home-manager modules.

Usage

Clone the repository:

git clone https://github.com/your-username/nix-darwin-config.git
cd nix-darwin-config

Install Nix: Follow the instructions on the Nix website to install Nix.

Enable Flakes: Ensure that flakes are enabled in your Nix configuration:

mkdir -p ~/.config/nix
echo "experimental-features = nix-command flakes" >> ~/.config/nix/nix.conf

Apply Configuration: To apply the configuration for a specific host, run:
```
nix build .#darwinConfigurations.<hostname>.system
./result/sw/bin/darwin-rebuild switch --flake .
```
Replace <hostname> with the actual hostname defined in the flake.nix file (e.g., swaphb-mba).

Adding New Hosts or Users

To add a new host or user, update the hostVars and userVars sections in the flake.nix file with the new configurations. Follow the existing structure to ensure consistency.

Example: Setting Variables in the Flake File

In the flake.nix file, you can define host-specific and user-specific variables using let-bindings. Here is an example:

let
  ###################################
  # 1. Host variables
  ###################################
  hostVars = {
    host1 = {
      hostname = "swaphb-mba";
      arch = "aarch64-darwin";
      homeDirectory = "/Users/stephen";
    };
    host2 = {
      hostname = "example";
      arch = "aarch64-darwin";
      homeDirectory = "/Users/example";
    };
  };

  ###################################
  # 2. User variables
  ###################################
  userVars = {
    userA = {
      username      = "stephen";
      homeDirectory = "/Users/stephen";
      shell         = "zsh";
    };
    userB = {
      username      = "example";
      homeDirectory = "/Users/example";
      shell         = "fish";
    };
  };
in
{
  // ...existing code...
}

These variables can then be used throughout the flake configuration to customize settings for each host and user.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Overview
Requirements
Repository Layout
Key Modules
How to Use
Building and Switching
Common Commands
Troubleshooting
Dirty Git Tree
Path Does Not Exist
References

Overview

nix-darwin: Brings the power of Nix on macOS for system-wide configurations.
Home Manager: Manages user-level configuration (dotfiles, shells, packages) using Nix.
nix-homebrew: Allows declarative management of Homebrew (including taps, casks, etc.) via Nix.

By splitting the configuration into multiple files under ./modules/, each file focuses on a specific area (e.g., system packages, services, dotfiles, etc.).

Requirements

Nix: You need Nix installed.
nix-darwin: The Darwin modules rely on nix-darwin.
Git: This is a Flake-based workflow, so your configuration should be in a Git repository.

After installing Nix, you can install nix-darwin (one recommended approach is from the official Nix-Darwin docs).

Repository Layout

A typical directory structure might look like this:

.
├── flake.nix
├── modules
│   ├── darwin
│   │   ├── homebrew.nix
│   │   ├── nixpackages.nix
│   │   └── services.nix
│   └── home
│       └── <username>
│           └── dotfiles.nix
├── rebuild.sh
└── README.md

flake.nix: The top-level file defining all inputs (nixpkgs, nix-darwin, home-manager, nix-homebrew) and outputs (your nix-darwin configuration). Imports each module (e.g., ./modules/darwin/homebrew.nix) into darwinConfigurations.<hostname>.modules.
modules/darwin/:
- homebrew.nix: Holds Homebrew-related configurations (brew packages, casks, etc.).
- nixpackages.nix: Holds your environment.systemPackages.
- services.nix: Configures system services (e.g., Tailscale, nix-daemon, security/pam).
modules/home/:
- <username>/dotfiles.nix: Holds user-level dotfiles managed by Home Manager (e.g., ~/.gitconfig, ~/.ssh/config).
rebuild.sh: A convenience script that typically runs something like:
```
#!/usr/bin/env bash
darwin-rebuild switch --flake .#<hostname>
```
Replace <hostname> with your actual hostname if needed.

Key Modules

modules/darwin/homebrew.nix

{ config, pkgs, lib, ... }:

{
  homebrew = {
    enable = true;
    onActivation.cleanup = "uninstall";
    taps = [];
    brews = [
      "cowsay" # install brews
      "git"
      "k9s"
      "helm"
      "podman"
      "podman-compose"
    ];
    casks = [
      "1password" # install casks
      "podman-desktop"
      "teleport-connect"
      "utm"
      "localsend"
    ];
    masApps = {
      "1Password for Safari" = 1569813296; # install Mac Appstore apps!
      "wireguard"            = 1451685025;
      "wipr"                 = 1320666476;
    };
  };
}

modules/darwin/nixpackages.nix

{ config, pkgs, ... }:

{
  environment.systemPackages = with pkgs; [
    vim # Install packages from nix package store
    lens
    vscode
    spotify
    slack
    kubectl
    discord
    _1password-cli
    brave
    teleport
    tenv
    google-cloud-sdk
    awscli
    azure-cli
    go
    starship
  ];
}

modules/darwin/services.nix

{ config, pkgs, ... }:

{
  services = {
    nix-daemon.enable = true;
    tailscale.enable = true; # Install and enable tailscale
  };

  security.pam.enableSudoTouchIdAuth = true;
}

modules/home/dotfiles.nix

{ config, pkgs, lib, ... }:

{
  home.file = {
    ".ssh/config".text = ''
      Host *
        IdentityAgent "~/Library/Group Containers/2BUA8C4S2C.com.1password/t/agent.sock" # enables 1password ssh agent integration
    '';

    ".gitconfig".text = ''
      [user]
        name = <name>
        email = <your_email>
        signingkey = <Your_Github_Auth_Public_Key>

      [gpg]
        format = ssh

      [gpg "ssh"]
        program = "/Applications/1Password.app/Contents/MacOS/op-ssh-sign" # Specify gpg sign key location, This uses 1password's provider.

      [commit]
        gpgSign = true
    '';
  };
}

How to Use

Building and Switching

Clone this repo (or ensure you have your local copy).
Install nix-darwin if you haven’t already.
From the root of this repository (where flake.nix resides), run:
```
darwin-rebuild switch --flake .#<hostname>
```
Replace <hostname> with the actual name of your system defined in flake.nix (e.g., swaphb-mba).

Alternatively, if you have a script rebuild.sh, run:

./rebuild.sh

which should do the same command under the hood.

Common Commands

Build without switching:
```
darwin-rebuild build --flake .#<hostname>
```
This only builds the configuration but doesn’t apply it.
Show changes:
```
darwin-rebuild dry-activate --flake .#<hostname>
```
See what changes will be made without applying them.
List available flake outputs:
```
nix flake show
```

Troubleshooting

Dirty Git Tree

If you see warnings like:

warning: Git tree '/path/to/your/repo' is dirty

It means you have uncommitted changes.

Solution: Either commit the changes or pass --impure (not recommended), or stage/commit the changes to keep the flake happy:

git add -A
git commit -m "Commit message"

Path Does Not Exist

If you get an error similar to:

error: path '/nix/store/...-source/modules/darwin/homebrew.nix' does not exist

It usually means:

You haven’t actually created or committed the file.
There’s a typo or case mismatch in the file name.
The file is in a different directory than you think.

Solution: Make sure the file exists, check for correct spelling/capitalization, and commit it to Git.

References

With this multi-file approach, you can easily add, remove, or tweak individual modules without having a giant monolithic flake.nix.

README.md Unescape Escape

Nix Darwin Configuration