diff --git a/maintainers/maintainer-list.nix b/maintainers/maintainer-list.nix
index 6e02c9c8cec3..4ed9383d5e04 100644
--- a/maintainers/maintainer-list.nix
+++ b/maintainers/maintainer-list.nix
@@ -7053,6 +7053,13 @@
     githubId = 5918766;
     name = "Franz Thoma";
   };
+  fnune = {
+    email = "fausto.nunez@mailbox.org";
+    github = "fnune";
+    githubId = 16181067;
+    name = "Fausto Núñez Alberro";
+    keys = [ { fingerprint = "668E 01D1 B129 3F42 0A0F  933A C880 6451 94A2 D562"; } ];
+  };
   foo-dogsquared = {
     email = "foodogsquared@foodogsquared.one";
     github = "foo-dogsquared";
diff --git a/pkgs/kde/default.nix b/pkgs/kde/default.nix
index 7d855dae05eb..ee011c3a7ae8 100644
--- a/pkgs/kde/default.nix
+++ b/pkgs/kde/default.nix
@@ -88,6 +88,7 @@ let
 
         applet-window-buttons6 = self.callPackage ./third-party/applet-window-buttons6 { };
         karousel = self.callPackage ./third-party/karousel { };
+        koi = self.callPackage ./third-party/koi { };
         krohnkite = self.callPackage ./third-party/krohnkite { };
         kzones = self.callPackage ./third-party/kzones { };
       }
diff --git a/pkgs/kde/third-party/koi/default.nix b/pkgs/kde/third-party/koi/default.nix
new file mode 100644
index 000000000000..1c1d3c92172b
--- /dev/null
+++ b/pkgs/kde/third-party/koi/default.nix
@@ -0,0 +1,55 @@
+{
+  lib,
+  stdenv,
+  fetchFromGitHub,
+  cmake,
+  kconfig,
+  kcoreaddons,
+  kwidgetsaddons,
+  wrapQtAppsHook,
+}:
+stdenv.mkDerivation rec {
+  pname = "koi";
+  version = "0.3.1";
+
+  src = fetchFromGitHub {
+    owner = "baduhai";
+    repo = "Koi";
+    rev = version;
+    sha256 = "sha256-dhpuKIY/Xi62hzJlnVCIOF0k6uoQ3zH129fLq/r+Kmg";
+  };
+
+  # See https://github.com/baduhai/Koi/blob/master/development/Nix%20OS/dev.nix
+  sourceRoot = "source/src";
+  nativeBuildInputs = [
+    cmake
+    wrapQtAppsHook
+  ];
+  buildInputs = [
+    kconfig
+    kcoreaddons
+    kwidgetsaddons
+  ];
+
+  meta = with lib; {
+    description = "Scheduling LIGHT/DARK Theme Converter for the KDE Plasma Desktop";
+    longDescription = ''
+      Koi is a program designed to provide the KDE Plasma Desktop functionality to automatically switch between light and dark themes. Koi is under semi-active development, and while it is stable enough to use daily, expect bugs. Koi is designed to be used with Plasma, and while some features may function under different desktop environments, they are unlikely to work and untested.
+
+      Features:
+
+      - Toggle between light and dark presets based on time
+      - Change Plasma style
+      - Change Qt colour scheme
+      - Change Icon theme
+      - Change GTK theme
+      - Change wallpaper
+      - Hide application to system tray
+      - Toggle between LIGHT/DARK themes by clicking mouse wheel
+    '';
+    license = licenses.lgpl3;
+    platforms = platforms.linux;
+    homepage = "https://github.com/baduhai/Koi";
+    maintainers = with lib.maintainers; [ fnune ];
+  };
+}