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
+  home.homeDirectory = if pkgs.stdenv.hostPlatform.isDarwin
-                       then /Users/${config.home.username} else /home/${config.home.username};
+                       then /Users/${config.home.username}
+                       else /home/${config.home.username};
 
   # Let Home Manager install and manage itself.
   programs.home-manager.enable = true;
@@ -11,8 +12,9 @@
   # Enable integration with generic Linux OSs
   targets.genericLinux.enable = pkgs.stdenv.isLinux;
 
-  home.packages = with pkgs; [
+  home.packages = with pkgs; let
-    # xonsh_with_plugins
+    isOnMac = stdenv.hostPlatform.isDarwin;
+    basePackages = [
       # Better cat
       bat
       # Better find
@@ -28,6 +30,11 @@
       fira-code-nerdfont
       roboto-mono
     ];
+    macPackages = basePackages ++ [
+      coreutils-prefixed
+    ];
+  in
+    if isOnMac then macPackages else basePackages;
 
   imports = [
     ./modules/fish