Use the correct filter for systems

darwin/brew.nix

@@ -4,7 +4,7 @@ with lib;
 {
   homebrew.enable = true;
   homebrew.brewPrefix =
-    if pkgs.system == "aarch64-darwin" then "/opt/homebrew/bin"
+    if pkgs.stdenv.isAarch64 then "/opt/homebrew/bin"
     else "/usr/local/bin";
   homebrew.onActivation.cleanup = "zap";
   homebrew.onActivation.upgrade = true;

home/common-linux.nix

@@ -4,7 +4,7 @@ with lib; {
     ./modules/linux/graphical
     ./modules/X11/xfce4-notifyd.nix
   ];
-  config = (mkIf (strings.hasSuffix "linux" pkgs.system) {
+  config = (mkIf pkgs.stdenv.isLinux {
     home.packages = with pkgs; [
       psmisc # killall and friends
 

modules/personal/fonts/default.nix

@@ -12,7 +12,7 @@ with lib;
       noto-fonts-cjk
       merriweather
     ];
-  } // (if (strings.hasSuffix "linux" pkgs.system) then {
+  } // (if pkgs.stdenv.isLinux then {
     enableDefaultFonts = false;
     fontconfig = {
       defaultFonts = {
@@ -23,7 +23,7 @@ with lib;
       };
     };
     fontDir.enable = true;
-  } else { }) // (if (strings.hasSuffix "darwin" pkgs.system) then {
+  } else { }) // (if pkgs.stdenv.isDarwin then {
     fontDir.enable = true;
   } else { });
 }

modules/personal/u2f.nix

@@ -13,7 +13,7 @@ in
     environment.systemPackages = with pkgs; [
       pam_u2f # for pamu2fcfg
     ];
-    security.pam = mkIf (strings.hasSuffix "linux" pkgs.system) {
+    security.pam = mkIf pkgs.stdenv.isLinux {
       u2f = {
         enable = true;
         cue = true;