feat: Add nix package

nix-app/default.nix

@@ -0,0 +1,55 @@
+{ pkgs ? import <nixpkgs> {} }:
+# Mostly taken from the cinny nix package
+let
+  # Destructure the necessary dependencies from pkgs
+  inherit (pkgs) stdenv lib dpkg fetchurl autoPatchelfHook glib-networking libayatana-appindicator openssl webkitgtk_4_1 wrapGAppsHook libcanberra-gtk3;
+in
+stdenv.mkDerivation rec {
+  name = "drop-oss-app";
+  version = "0.3.3";
+
+  src = fetchurl {
+    url = "https://github.com/Drop-OSS/drop-app/releases/download/v${version}/Drop.Desktop.Client_${version}_amd64.deb";
+    sha256 = "sha256-w9pnYds8m8DASzCDN3Bp+UF1CcrW24G274OLVdnzIkI=";
+  };
+
+  nativeBuildInputs = [
+    autoPatchelfHook
+    dpkg
+  ];
+
+  buildInputs = [
+    glib-networking
+    openssl
+    webkitgtk_4_1
+    wrapGAppsHook
+    libayatana-appindicator
+    pkgs.gdk-pixbuf
+    pkgs.gtk3
+    libcanberra-gtk3
+    pkgs.mesa
+    pkgs.xorg.libX11
+    pkgs.xorg.libXext
+  ];
+
+  unpackCmd = "dpkg-deb -x $curSrc source";
+  installPhase = "mv usr $out";
+
+  postFixup = ''
+    # Ensure libraries get injected
+    local libPath=${lib.makeLibraryPath buildInputs}
+
+    wrapProgram $out/bin/drop-app \
+      --set LD_LIBRARY_PATH "$libPath"
+  '';
+
+  meta = with lib; {
+    description = " The desktop companion app for Drop. It acts a download client, game launcher and game distribution endpoint for Drop. ";
+    homepage = "https://droposs.org";
+    maintainers = [ "quexeky" ];
+    license = licenses.agpl3Only;
+    sourceProvenance = with sourceTypes; [ binaryNativeCode ];
+    platforms = platforms.linux;
+    mainProgram = "drop-app";
+  };
+}