add current state I use of

https://github.com/nix-community/nixos-apple-silicon

zeta/apple-silicon-support/modules/mesa/default.nix

@@ -0,0 +1,53 @@
+{ options, config, pkgs, lib, ... }:
+{
+  config = let
+    isMode = mode: (config.hardware.asahi.useExperimentalGPUDriver
+        && config.hardware.asahi.experimentalGPUInstallMode == mode);
+  in lib.mkIf config.hardware.asahi.enable (lib.mkMerge [
+    {
+      # required for proper DRM setup even without GPU driver
+      services.xserver.config = ''
+        Section "OutputClass"
+            Identifier "appledrm"
+            MatchDriver "apple"
+            Driver "modesetting"
+            Option "PrimaryGPU" "true"
+        EndSection
+      '';
+    }
+    (lib.mkIf config.hardware.asahi.useExperimentalGPUDriver {
+      # install the Asahi Mesa version
+      hardware.graphics.package = config.hardware.asahi.pkgs.mesa-asahi-edge;
+      # required for in-kernel GPU driver
+      hardware.asahi.withRust = true;
+    })
+  ]);
+
+  options.hardware.asahi.useExperimentalGPUDriver = lib.mkOption {
+    type = lib.types.bool;
+    default = false;
+    description = ''
+      Use the experimental Asahi Mesa GPU driver.
+
+      Do not report issues using this driver under NixOS to the Asahi project.
+    '';
+  };
+
+  # hopefully no longer used, should be deprecated eventually
+  options.hardware.asahi.experimentalGPUInstallMode = lib.mkOption {
+    type = lib.types.enum [ "driver" "replace" "overlay" ];
+    default = "replace";
+    description = ''
+      Mode to use to install the experimental GPU driver into the system.
+
+      driver: install only as a driver, do not replace system Mesa.
+        Causes issues with certain programs like Plasma Wayland.
+
+      replace (default): use replaceRuntimeDependencies to replace system Mesa with Asahi Mesa.
+        Does not work in pure evaluation context (i.e. in flakes by default).
+
+      overlay: overlay system Mesa with Asahi Mesa
+        Requires rebuilding the world.
+    '';
+  };
+}