Support running arm code on x86.

nix/configuration/configuration.nix

@@ -22,6 +22,7 @@
     ./roles/docker
     ./roles/ecc
     ./roles/emacs
+    ./roles/emulate_isa
     ./roles/firefox
     ./roles/firewall
     ./roles/flux

nix/configuration/hosts/odo/default.nix

@@ -71,6 +71,7 @@
     me.docker.enable = false;
     me.ecc.enable = false;
     me.emacs_flavor = "full";
+    me.emulate_isa.enable = true;
     me.firefox.enable = true;
     me.flux.enable = true;
     me.gcloud.enable = true;

nix/configuration/hosts/quark/default.nix

@@ -64,6 +64,7 @@
     me.docker.enable = false;
     me.ecc.enable = true;
     me.emacs_flavor = "full";
+    me.emulate_isa.enable = true;
     me.firefox.enable = true;
     me.flux.enable = true;
     me.gcloud.enable = true;

nix/configuration/roles/emulate_isa/default.nix

@@ -0,0 +1,33 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+{
+  imports = [ ];
+
+  options.me = {
+    emulate_isa.enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      example = true;
+      description = "Whether we want to enable emulating other CPU architectures.";
+    };
+  };
+
+  config = lib.mkIf config.me.emulate_isa.enable (
+    lib.mkMerge [
+      {
+        boot.binfmt.emulatedSystems = [
+          "aarch64-linux" # Raspberry Pi gen 3
+          "riscv64-linux"
+          # TODO: Should "x86_64-linux" be in this list or should this list be dependent on the host CPU?
+          "armv6l-linux" # Raspberry Pi gen 1
+        ];
+      }
+    ]
+  );
+}
+# NOTE: build nixosConfigurations.<name>.config.system.build.sdImage