Cross-Platform Nix Configuration

A unified Nix configuration supporting both macOS (via nix-darwin) and Linux (via Home Manager standalone).

Supported Platforms

Platform	Architecture	Configuration
macOS	aarch64 (Apple Silicon)	darwinConfigurations."william-2"
Linux	x86_64	homeConfigurations."guoshengwei@linux"
Linux	aarch64	homeConfigurations."guoshengwei@linux-arm"

Directory Structure

/private/etc/nix-darwin/
├── flake.nix                      # Main entry point
├── flake.lock
├── README.md
│
├── modules/
│   ├── common/                    # Cross-platform shared modules
│   │   ├── packages.nix           # Cross-platform packages (~70+)
│   │   ├── home-base.nix          # Home Manager base settings
│   │   └── programs/
│   │       ├── zsh.nix            # Zsh configuration (with platform detection)
│   │       ├── git.nix            # Git configuration
│   │       ├── direnv.nix         # Direnv configuration
│   │       └── vim.nix            # Vim configuration
│   │
│   ├── darwin/                    # macOS-specific modules
│   │   ├── default.nix            # Darwin system configuration
│   │   ├── homebrew.nix           # Homebrew packages
│   │   ├── window-manager.nix     # yabai/skhd configuration
│   │   └── home.nix               # macOS Home Manager extensions
│   │
│   └── linux/                     # Linux-specific modules
│       ├── default.nix            # Linux Home Manager entry
│       └── packages.nix           # Linux-specific packages (X11, GNOME)
│
├── hosts/                         # Host-specific configurations
│   ├── william-2/default.nix      # macOS host
│   └── linux/default.nix          # Linux host
│
├── users/                         # User configurations
│   └── guoshengwei/default.nix
│
└── config/                        # Dotfiles
    ├── doom/                      # Doom Emacs configuration
    ├── gitconfig/                 # Git configuration files
    ├── vimrc                      # Vim configuration
    ├── yabairc                    # yabai configuration (macOS)
    ├── skhdrc                     # skhd configuration (macOS)
    └── ...

Quick Start

macOS

# Build the configuration
darwin-rebuild build --flake .#william-2

# Apply the configuration
darwin-rebuild switch --flake .#william-2

Linux

# Install Nix (if not already installed)
sh <(curl -L https://nixos.org/nix/install) --daemon

# Install Home Manager
nix-channel --add https://github.com/nix-community/home-manager/archive/master.tar.gz home-manager
nix-channel --update

# Apply the configuration (x86_64)
nix run home-manager -- switch --flake .#guoshengwei@linux

# Or for ARM Linux
nix run home-manager -- switch --flake .#guoshengwei@linux-arm

Package Categories

Cross-Platform Packages (modules/common/packages.nix)

Category	Packages
Development	gcc, cmake, nodejs, python313, go, clisp
CLI Tools	bat, eza, tree, lazygit, direnv
Scientific Computing	eigen, ceres-solver, openblas, hdf5, suitesparse
Image Processing	tesseract, ghostscript, libwebp, libjpeg_turbo
Font Rendering	fontconfig, freetype, harfbuzz, cairo, pango
Compression	openssl, lzo, libb2, libdeflate

macOS-Only (via Homebrew)

Category	Packages
Window Manager	yabai, skhd
Editor	emacs-plus@29
TeX	mactex-no-gui
Fonts	font-meslo-lg-nerd-font

Linux-Only (modules/linux/packages.nix)

Category	Packages
X11	xorg.libX11, xorg.libXext, xorg.libxcb, etc.
GNOME/GTK	gdk-pixbuf, dbus, at-spi2-core, adwaita-icon-theme

Customization

Adding a New Package

1. Cross-platform package: Add to modules/common/packages.nix
2. macOS-only package: Add to modules/darwin/homebrew.nix (for Homebrew) or modules/darwin/home.nix (for Nix)
3. Linux-only package: Add to modules/linux/packages.nix

Adding a New Program Configuration

Create a new file in modules/common/programs/ and import it in modules/common/home-base.nix:

# modules/common/programs/myprogram.nix
{ config, pkgs, lib, isDarwin ? true, ... }:

{
  programs.myprogram = {
    enable = true;
    # Platform-specific settings
    settings = lib.optionalAttrs isDarwin {
      # macOS settings
    } // lib.optionalAttrs (!isDarwin) {
      # Linux settings
    };
  };
}

Adding a New Host

1. Create hosts/hostname/default.nix
2. Add the configuration to flake.nix

Platform Detection

The configuration uses an isDarwin boolean passed to modules:

{ config, pkgs, lib, isDarwin ? true, ... }:

{
  # Cross-platform settings
  home.packages = with pkgs; [
    common-package
  ] ++ lib.optionals isDarwin [
    darwin-only-package
  ] ++ lib.optionals (!isDarwin) [
    linux-only-package
  ];

  # Conditional strings in config
  programs.zsh.initExtra = ''
    # Common config
    ${lib.optionalString isDarwin ''
      # macOS-specific
    ''}
  '';
}

Troubleshooting

macOS: darwin-rebuild fails

# Check flake syntax
nix flake check

# Build with verbose output
darwin-rebuild build --flake .#william-2 --show-trace

Linux: Home Manager switch fails

# Check if Nix is properly configured
nix --version

# Build with verbose output
home-manager switch --flake .#guoshengwei@linux --show-trace

Zsh: Path or alias errors

• Check if the platform detection is working correctly
• Verify isDarwin is being passed to the zsh module
• Check ~/.zshrc for any syntax errors

Doom Emacs: mac-option-modifier not working on Linux

The config/doom/config.el uses platform detection:

(when (eq system-type 'darwin)
  (setq mac-option-modifier 'meta)
  (setq mac-right-option-modifier 'meta))

Development

Enter the development shell:

nix develop

This provides:

• nixpkgs-fmt - Nix code formatter
• nil - Nix LSP for IDE integration

License

Personal configuration - feel free to use as a reference for your own setup.