Use pkgsCross

flake.nix

@@ -438,7 +438,7 @@
                   # otherwise, they will likely have no effect anyways
                   text = ''
                     command -v powerprofilesctl &>/dev/null && bash -x -c 'powerprofilesctl set performance'
-                    command -v swaymsg &>/dev/null && bash -x -c 'swaymsg output eDP-1 mode 2880x1920@60Hz'
+                    command -v swaymsg &>/dev/null && bash -x -c 'swaymsg output eDP-1 mode 2880x1920@120Hz'
                   '';
                 })
               (writeShellApplication
@@ -657,28 +657,23 @@
       #   .disk-image;
 
       pinephone = let
-        system = "aarch64-linux";
         inherit (nixpkgs-unstable) lib;
       in
-        lib.nixosSystem {
-          inherit system;
-          modules = with nixosModules; [
+        nixpkgs-unstable.legacyPackages.${builtins.currentSystem}.pkgsCross.aarch64-multiplatform.nixos {
+          imports = with nixosModules; [
             # TODO: how do I build this as a .img to flash to an SD card?
 
             # for testing, this seems to work `nixos-rebuild build --impure --flake .#pinephone`
 
-            {
-              # enable cross-compiling with impure
-              nixpkgs.buildPlatform = builtins.currentSystem;
-              nixpkgs.hostPlatform = system;
-            }
+            # TODO: would like to use the mobile-nixos installer?
+            # "${nixpkgs-unstable}/nixos/modules/installer/sd-card/sd-image-aarch64-installer.nix"
 
-            linux
-            home-manager-unstable-defaults
+            # linux
+            # home-manager-unstable-defaults
 
             # outputs.diskoConfigurations.unencrypted # can I even disko with an image-based installation?
-            common
-            wifi
+            # common
+            # wifi
 
             {
               system.stateVersion = "24.11";
@@ -686,7 +681,9 @@
 
             {
               imports = [
-                (import "${mobile-nixos}/lib/configuration.nix" {device = "pine64-pinephone";})
+                (import "${mobile-nixos}/lib/configuration.nix" {
+                  device = "pine64-pinephone";
+                })
               ];
 
               # TODO: quirk: since the pinephone kernel doesn't seem to have "rpfilter" support, firewall ain't working