Add a way to build the UEFI iso

build-iso.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+set -e
+set -u
+PS4=" $ "
+
+# Ugh, I would have liked to do it through a simpler `nix-build`, but  as this
+# needs to set `NIX_PATH` for use of `<nixpkgs/*>` imports, this is the better
+# way to go.
+
+set -x
+exec env -i \
+	NIXPKGS_ALLOW_UNFREE=1 \
+	NIX_PATH="nixpkgs=channel:nixos-unstable" \
+	"$(command -v nix-build)" \
+	iso.nix -A config.system.build.isoImage "$@"

iso.nix

@@ -0,0 +1,12 @@
+import <nixpkgs/nixos> {
+  configuration = {
+    imports = [
+      (
+        if builtins.currentSystem == "aarch64-linux"
+        then builtins.toPath (./. + "/configuration.nix")
+        else builtins.toPath (./. + "/with-cross.nix")
+        )
+        <nixpkgs/nixos/modules/installer/cd-dvd/installation-cd-minimal.nix>
+      ];
+    };
+  }