feat: add a nix default

default.nix

@@ -0,0 +1,44 @@
+{
+  description = "Nix flake to use indieweb static files as a theme for website deployment";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+      in {
+        packages = rec {
+          indiewebTheme = pkgs.stdenv.mkDerivation {
+            pname = "indieweb-theme";
+            version = "1.0.0";
+
+            src = ./.;
+
+            installPhase = ''
+              mkdir -p $out/themes/indieweb
+              cp -r archetypes theme.toml layouts static $out/themes/indieweb
+            '';
+
+            meta = with pkgs.lib; {
+              description = "Static files for the indieweb theme to be used in the website deployment";
+              homepage = "https://your-homepage-url";
+              license = licenses.mit;
+              maintainers = [ maintainers.yourname ];
+              platforms = platforms.unix;
+            };
+          };
+        };
+
+        defaultPackage.${system} = self.packages.${system}.indiewebTheme;
+
+        apps = rec {
+          indiewebTheme = flake-utils.lib.mkApp { drv = self.packages.${system}.indiewebTheme; };
+          default = indiewebTheme;
+        };
+      }
+    );
+}