Create minimal and graphical ISOs

flake.nix

@@ -71,6 +71,9 @@
         _: host: host.config.system.build.toplevel
       ) self.nixosConfigurations;
 
-      hydraJobs.isos.installer = self.nixosConfigurations.installer.config.system.build.isoImage;
+      hydraJobs.isos = {
+        installer-minimal = self.nixosConfigurations.installer-minimal.config.system.build.isoImage;
+        installer-graphical = self.nixosConfigurations.installer-graphical.config.system.build.isoImage;
+      };
     };
 }

hosts/x86_64-linux/installer-graphical.nix

@@ -0,0 +1,9 @@
+{ nixpkgs-flake, ... }:
+{
+  imports = [
+    "${nixpkgs-flake}/nixos/modules/installer/cd-dvd/installation-cd-graphical-combined.nix"
+  ];
+  custom.platform.installer.enable = true;
+  isoImage.squashfsCompression = "zstd";
+  system.installer.channel.enable = false;
+}

hosts/x86_64-linux/installer-minimal.nix

@@ -0,0 +1,9 @@
+{ nixpkgs-flake, ... }:
+{
+  imports = [
+    "${nixpkgs-flake}/nixos/modules/installer/cd-dvd/installation-cd-minimal.nix"
+  ];
+  custom.platform.installer.enable = true;
+  isoImage.squashfsCompression = "zstd";
+  system.installer.channel.enable = false;
+}

hosts/x86_64-linux/installer.nix

@@ -1,32 +0,0 @@
-{
-  config,
-  nixpkgs-flake,
-  lib,
-  pkgs,
-  ...
-}:
-let
-  zfs = pkgs.zfsUnstable.override {
-    # this overrides saves 10MB
-    samba = pkgs.coreutils;
-
-    python3 = pkgs.python3Minimal;
-  };
-in
-{
-  imports = [
-    "${nixpkgs-flake}/nixos/modules/installer/cd-dvd/installation-cd-graphical-combined.nix"
-  ];
-
-  # This block modified from https://github.com/nix-community/nixos-images
-  boot.zfs.package = zfs;
-  environment.defaultPackages = lib.mkForce [ zfs ];
-  boot.kernelModules = [ "zfs" ];
-  boot.extraModulePackages = [ config.boot.kernelPackages.zfs_unstable ];
-
-  custom.services.nixCacheClient.enable = true;
-  services.qemuGuest.enable = true;
-  system.installer.channel.enable = false;
-  isoImage.squashfsCompression = "zstd";
-  networking.wireless.enable = false;
-}

modules/platform/installer.nix

@@ -0,0 +1,20 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.custom.platform.installer;
+in
+{
+  options.custom.platform.installer.enable = lib.mkEnableOption "installer ISO configuration";
+
+  config = lib.mkIf cfg.enable {
+    boot.supportedFilesystems.zfs = lib.mkForce true;
+    users.defaultUserShell = lib.mkForce pkgs.bash;
+    custom.services.nixCacheClient.enable = true;
+    services.qemuGuest.enable = true;
+    networking.wireless.enable = false;
+  };
+}