Add Nix package

package.nix

@@ -0,0 +1,43 @@
+{
+  lib,
+  rustPlatform,
+  pkg-config,
+  wrapGAppsHook4,
+  pcsclite,
+  gtk4,
+  libadwaita,
+  openssl
+}:
+
+rustPlatform.buildRustPackage rec {
+  pname = "xenid";
+  version = "0.1.0";
+
+  src = ./.;
+
+  cargoHash = "sha256-hrxH1Cxuf6oaVKuEDoB6W1qYdxlJ+dstU58ZO0NY+xg=";
+
+  nativeBuildInputs = [
+    pkg-config
+    wrapGAppsHook4
+  ];
+
+  buildInputs = [
+    openssl
+    gtk4
+    pcsclite
+    libadwaita
+  ];
+
+  postInstall = ''
+    install -D data/moe.puck.XeniD.desktop -t $out/share/applications
+  '';
+
+  meta = {
+    description = "DigiD eID client for Linux";
+    license = lib.licenses.eupl12;
+    maintainers = with lib.maintainers; [ puckipedia ];
+    mainProgram = "xenid";
+  };
+}
+