Add a nix-darwin config for a m1 mac mini.

nix/nix-darwin/flake.lock

@@ -0,0 +1,49 @@
+{
+  "nodes": {
+    "nix-darwin": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1785389976,
+        "narHash": "sha256-0tLW8Ff5yt8AH97jw4ZpFJ0OCJ122zIlgWGDmOfU/VU=",
+        "owner": "nix-darwin",
+        "repo": "nix-darwin",
+        "rev": "15abb8c98f336cd8bd840d71059adebabe60bf04",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-darwin",
+        "ref": "master",
+        "repo": "nix-darwin",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1786348146,
+        "narHash": "sha256-we5zDEFfn8TgzeWKjKDMIjeQZ59omEPl23NIF+13/ys=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "d482ef84049d9b7276b83a06e4e4d76983830097",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nix-darwin": "nix-darwin",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

nix/nix-darwin/flake.nix

@@ -0,0 +1,128 @@
+# Initial install:
+#   Install nix: https://github.com/nixOS/nix-installer
+#   sudo nix run nix-darwin -- switch --flake .#garak
+#
+# Update after that:
+#   sudo darwin-rebuild switch --flake .#garak
+#
+# Manual:
+#   Install rosetta to run x86_64 programs:
+#   softwareupdate --install-rosetta --agree-to-license
+#
+#   Install homebrew for installing graphical apps:
+#   /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+{
+  description = "nix-darwin system flake";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    nix-darwin.url = "github:nix-darwin/nix-darwin/master";
+    nix-darwin.inputs.nixpkgs.follows = "nixpkgs";
+  };
+
+  outputs = inputs@{ self, nix-darwin, nixpkgs }:
+  let
+    configuration = { pkgs, ... }: {
+      # List packages installed in system profile. To search by name, run:
+      # $ nix-env -qaP | grep wget
+      environment.systemPackages =
+        [
+          pkgs.tmux
+          pkgs.htop
+          pkgs.git
+        ];
+
+      # Necessary for using flakes on this system.
+      nix.settings.experimental-features = "nix-command flakes";
+
+      # Enable alternative shell support in nix-darwin.
+      # programs.fish.enable = true;
+
+      # Set Git commit hash for darwin-version.
+      system.configurationRevision = self.rev or self.dirtyRev or null;
+
+      # Used for backwards compatibility, please read the changelog before changing.
+      # $ darwin-rebuild changelog
+      system.stateVersion = 6;
+
+      # The platform the configuration will be used on.
+      nixpkgs.hostPlatform = "aarch64-darwin";
+
+      # Identifies which user some settings apply to.
+      system.primaryUser = "talexander";
+
+      # Enable Linux VM for building Linux binaries.
+      #
+      # Test with:
+      #   nix build --impure --expr '(with import <nixpkgs> { system = "aarch64-linux"; }; runCommand "foo" {} "uname -a > $out")'
+      nix.linux-builder.enable = true;
+
+      # system.defaults.CustomUserPreferences = {
+      #   "com.apple.desktopservices" = {
+      #     # Do not write .DS_Store files to external volumes
+      #     DSDontWriteNetworkStores = true;
+      #     DSDontWriteUSBStores = true;
+      #   };
+      #   "com.apple.screensaver" = {
+      #     # Ask for password when returning from screensaver
+      #     askForPassword = 1;
+      #     askForPasswordDelay = 0;
+      #   };
+      #   "com.apple.SoftwareUpdate" = {
+      #     AutomaticCheckEnabled = true;
+      #     # Download updates in the background
+      #     AutomaticDownload = 1;
+      #   };
+      # };
+
+      # Use homebrew to install graphical apps from casks.
+      # homebrew = {
+      #   enable = false;
+
+      #   casks = [
+      #     "firefox"
+      #   ];
+      # };
+
+      # system.defaults = {
+      #   dock = {
+      #     autohide = true;
+      #   };
+      # };
+
+      environment.variables = {
+        TERMINFO_DIRS = ["${pkgs.alacritty.terminfo.outPath}/share/terminfo"];
+      };
+
+      power = {
+        sleep = {
+          # sudo pmset -a displaysleep 10 sleep 0 disksleep 10
+          # Other options to consider: lowpowermode 0 standby 0 hibernatemode 0 powernap 0
+          #
+          # Defaults:
+          #   standby              0
+          #   Sleep On Power Button 1
+          #   autorestartatconnect 0
+          #   autorestart          0
+          #   powernap             1
+          #   networkoversleep     0
+          #   disksleep            10
+          #   sleep                1
+          #   ttyskeepawake        1
+          #   displaysleep         10
+          #   tcpkeepalive         1
+          #   womp                 1
+          #
+          computer = "never";
+          display = 10;
+          harddisk = 10;
+        };
+      };
+    };
+  in
+  {
+    darwinConfigurations."garak" = nix-darwin.lib.darwinSystem {
+      modules = [ configuration ];
+    };
+  };
+}