Nix: Add prefixed GNU coreutils on Mac

Necessary for some Emacs modes that expect a "gls" command.

nix/home.nix

@@ -1,9 +1,10 @@
 { config, pkgs, lib, ... }:
 {
   home.stateVersion = "22.05";
-  # TODO - ask for sanity check
-  home.homeDirectory = if lib.strings.hasInfix "darwin" pkgs.system
-                       then /Users/${config.home.username} else /home/${config.home.username};
+
+  home.homeDirectory = if pkgs.stdenv.hostPlatform.isDarwin
+                       then /Users/${config.home.username}
+                       else /home/${config.home.username};
 
   # Let Home Manager install and manage itself.
   programs.home-manager.enable = true;
@@ -11,23 +12,29 @@
   # Enable integration with generic Linux OSs
   targets.genericLinux.enable = pkgs.stdenv.isLinux;
 
-  home.packages = with pkgs; [
-    # xonsh_with_plugins
-    # Better cat
-    bat
-    # Better find
-    fd
-    # Better df
-    duf
-    # Better top
-    htop
-    ncdu
-    ripgrep
-    tmux
-    fira-code
-    fira-code-nerdfont
-    roboto-mono
-  ];
+  home.packages = with pkgs; let
+    isOnMac = stdenv.hostPlatform.isDarwin;
+    basePackages = [
+      # Better cat
+      bat
+      # Better find
+      fd
+      # Better df
+      duf
+      # Better top
+      htop
+      ncdu
+      ripgrep
+      tmux
+      fira-code
+      fira-code-nerdfont
+      roboto-mono
+    ];
+    macPackages = basePackages ++ [
+      coreutils-prefixed
+    ];
+  in
+    if isOnMac then macPackages else basePackages;
 
   imports = [
     ./modules/fish