diff --git a/modules/home-manager/programs/calendar.nix b/modules/home-manager/programs/calendar.nix
deleted file mode 100644
index e5c66d0..0000000
--- a/modules/home-manager/programs/calendar.nix
+++ /dev/null
@@ -1,35 +0,0 @@
-{ config, lib, ... }:
-
-let
-  cfg = config.local.programs.calendar;
-
-  mkCalOpts = name: {
-    enable = lib.mkEnableOption name;
-
-    # Custom package doesn't work yet.
-    # See: https://github.com/nix-community/home-manager/pull/5428
-    # package = lib.mkPackageOption pkgs name { };
-  };
-in
-{
-  options.local.programs.calendar = {
-    khal = mkCalOpts "khal";
-  };
-
-  config = {
-    accounts.calendar.basePath = "${config.xdg.dataHome}/calendars";
-
-    programs.khal = lib.mkIf cfg.khal.enable {
-      enable = true;
-      locale = rec {
-        timeformat = "%H:%M";
-        dateformat = "%Y-%m-%d";
-        longdateformat = dateformat;
-        datetimeformat = "${dateformat} ${timeformat}";
-        longdatetimeformat = datetimeformat;
-      };
-      # See: https://khal.readthedocs.io/en/latest/configure.html
-      settings = {};
-    };
-  };
-}
diff --git a/modules/home-manager/programs/calendar/default.nix b/modules/home-manager/programs/calendar/default.nix
new file mode 100644
index 0000000..fcb7354
--- /dev/null
+++ b/modules/home-manager/programs/calendar/default.nix
@@ -0,0 +1,6 @@
+{ config, ...}:
+{
+  imports = [./khal.nix];
+
+  config.accounts.calendar.basePath = "${config.xdg.dataHome}/calendars";
+}
diff --git a/modules/home-manager/programs/calendar/khal.nix b/modules/home-manager/programs/calendar/khal.nix
new file mode 100644
index 0000000..72d4dfa
--- /dev/null
+++ b/modules/home-manager/programs/calendar/khal.nix
@@ -0,0 +1,27 @@
+{ config, lib, ... }:
+
+let cfg = config.local.programs.calendar; in
+{
+  options.local.programs.calendar.khal = {
+    enable = lib.mkEnableOption "khal";
+
+    # Custom package doesn't work yet.
+    # See: https://github.com/nix-community/home-manager/pull/5428 
+    # package = lib.mkPackageOption pkgs "khal" { };
+  };
+
+  config = {
+    programs.khal = lib.mkIf cfg.khal.enable {
+      enable = true;
+      locale = rec {
+        timeformat = "%H:%M";
+        dateformat = "%d.%m.";
+        longdateformat = "%d.%m.%Y";
+        datetimeformat = "${dateformat} ${timeformat}";
+        longdatetimeformat = "${longdateformat} ${timeformat}";
+      };
+      # See: https://khal.readthedocs.io/en/latest/configure.html 
+      settings = { };
+    };
+  };
+}
diff --git a/modules/home-manager/programs/default.nix b/modules/home-manager/programs/default.nix
index fbc7456..7ce761c 100644
--- a/modules/home-manager/programs/default.nix
+++ b/modules/home-manager/programs/default.nix
@@ -3,12 +3,12 @@
 {
   imports = [
     ./aerc.nix
-    ./calendar.nix
     ./communication.nix
     ./dev-tools.nix
     ./flameshot.nix
     ./libreoffice.nix
     ./share-files.nix
+    ./calendar
     ./editors
     ./file-managers
     ./terminals
diff --git a/modules/nixos/configs/nix.nix b/modules/nixos/configs/nix.nix
index aa47876..e0bf4a7 100644
--- a/modules/nixos/configs/nix.nix
+++ b/modules/nixos/configs/nix.nix
@@ -42,9 +42,6 @@ in
           };
         };
       })
-      (final: prev: {
-        khal = (import inputs.nixpkgs-unstable { inherit (config.nixpkgs) system; }).khal;
-      })
       (final: prev: {
         unstable = import inputs.nixpkgs-unstable {
           inherit (config.nixpkgs) config overlays system;