Add support for exfat.

nix/configuration/configuration.nix

@@ -36,6 +36,7 @@ in
     ./roles/emacs
     ./roles/emulate_isa
     ./roles/esim
+    ./roles/exfat
     ./roles/firefox
     ./roles/firewall
     ./roles/flux

nix/configuration/hosts/odo/default.nix

@@ -94,6 +94,7 @@
     me.emacs_flavor = "full";
     me.emulate_isa.enable = true;
     me.esim.enable = true;
+    me.exfat.enable = true;
     me.firefox.enable = true;
     me.firewall.enable = true;
     me.flux.enable = true;

nix/configuration/roles/exfat/default.nix

@@ -0,0 +1,26 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+{
+  imports = [ ];
+
+  options.me = {
+    exfat.enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      example = true;
+      description = "Whether we want to install exfat.";
+    };
+  };
+
+  config = lib.mkIf config.me.exfat.enable {
+    # boot.supportedFilesystems = [ "exfat" ];
+    environment.systemPackages = with pkgs; [
+      exfatprogs
+    ];
+  };
+}