Nix modules for darwin, /etc/nixos/configuration.nix for macOS.

This project aims to bring the convenience of a declarative system approach to macOS. nix-darwin is built up around Nixpkgs, quite similar to NixOS.

The only prerequisite is a Nix implementation; both Nix and Lix are supported.

As the official Nix installer does not include an automated uninstaller, and manual uninstallation on macOS is a complex process, we recommend using one of the following installers instead:

• The Nix installer from Determinate Systems is only recommended for use with flake-based setups. It can install one of two distributions of Nix:

  • To install the recommended vanilla upstream Nix, you will need to explicitly say no when prompted to install Determinate Nix.

  • When run with the --determinate flag, it will install the Determinate distribution. As Determinate manages the Nix installation itself, you will need to set nix.enable = false; in your configuration to disable nix-darwin’s own Nix management. Some nix-darwin functionality that relies on managing the Nix installation, like the nix.* options to adjust Nix settings or configure a Linux builder, will be unavailable.

• The Lix installer supports both flake-based and channel-based setups.

Despite being an experimental feature in Nix currently, nix-darwin recommends that beginners use flakes to manage their nix-darwin configurations.

sudo mkdir -p /etc/nix-darwin
sudo chown $(id -nu):$(id -ng) /etc/nix-darwin
cd /etc/nix-darwin

# To use Nixpkgs unstable:
nix flake init -t nix-darwin/master
# To use Nixpkgs 25.05:
nix flake init -t nix-darwin/nix-darwin-25.05

sed -i '' "s/simple/$(scutil --get LocalHostName)/" flake.nix

{
  description = "John's darwin system";

  inputs = {
    # Use `github:NixOS/nixpkgs/nixpkgs-25.05-darwin` to use Nixpkgs 25.05.
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    # Use `github:nix-darwin/nix-darwin/nix-darwin-25.05` to use Nixpkgs 25.05.
    nix-darwin.url = "github:nix-darwin/nix-darwin/master";
    nix-darwin.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = inputs@{ self, nix-darwin, nixpkgs }: {
    darwinConfigurations."Johns-MacBook" = nix-darwin.lib.darwinSystem {
      modules = [ ./configuration.nix ];
    };
  };
}

# To use Nixpkgs unstable:
sudo nix run nix-darwin/master#darwin-rebuild -- switch
# To use Nixpkgs 25.05:
sudo nix run nix-darwin/nix-darwin-25.05#darwin-rebuild -- switch

sudo darwin-rebuild switch

# in flake.nix
nix-darwin.lib.darwinSystem {
  modules = [ ./configuration.nix ];
  specialArgs = { inherit inputs; };
}

# in configuration.nix
{ pkgs, lib, inputs }:
# inputs.self, inputs.nix-darwin, and inputs.nixpkgs can be accessed here

# If you use Nixpkgs unstable (the default):
sudo nix-channel --add https://github.com/nix-darwin/nix-darwin/archive/master.tar.gz darwin
# If you use Nixpkgs 25.05:
sudo nix-channel --add https://github.com/nix-darwin/nix-darwin/archive/nix-darwin-25.05.tar.gz darwin

sudo nix-channel --update

nix-build '<darwin>' -A darwin-rebuild
sudo ./result/bin/darwin-rebuild switch -I darwin-config=/etc/nix-darwin/configuration.nix

sudo darwin-rebuild switch

sudo nix-channel --update

darwin-help will open up a local copy of the reference documentation, it can also be found online here.

The documentation is also available as manpages by running man 5 configuration.nix.

To run the latest version of the uninstaller, you can run the following command:

sudo nix --extra-experimental-features "nix-command flakes" run nix-darwin#darwin-uninstaller

If that command doesn't work for you, you can try the locally installed uninstaller:

sudo darwin-uninstaller

There are basic tests that run sanity checks for some of the modules, you can run them like this:

# run all tests
nix-build release.nix -A tests
# or just a subset
nix-build release.nix -A tests.environment-path

Let's make Nix on macOS awesome!

Don't hesitate to contribute modules or open an issue.

To build your configuration with local changes you can run this. This flag can also be used to override darwin-config or nixpkgs, for more information on the -I flag look at the nix-build manpage.

sudo darwin-rebuild switch -I darwin=.

If you're adding a module, please add yourself to meta.maintainers, for example

  meta.maintainers = [
    lib.maintainers.alice or "alice"
  ];

  options.services.alicebot = # ...

The or operator takes care of graceful degradation when lib from Nixpkgs goes out of sync.

Feel free to contact us on Matrix if you have questions:

• User support: #macos:nixos.org
• Development discussion: #nix-darwin-dev:nixos.org