add optional nix flake

flake.nix

@@ -6,30 +6,90 @@
   };
 
   outputs =
-    { self, nixpkgs }:
+    {
+      self,
+      nixpkgs,
+    }:
     let
       forAllSystems =
         f:
         nixpkgs.lib.genAttrs nixpkgs.lib.systems.flakeExposed (
           system:
           f rec {
-            pkgs = nixpkgs.legacyPackages.${system};
             inherit system;
+            pkgs = nixpkgs.legacyPackages.${system};
+            selfPkgs = self.packages.${system};
+            lib = pkgs.lib;
           }
         );
     in
     {
-      devShells = forAllSystems (
-        { pkgs, ... }:
+      packages = forAllSystems (
         {
-          default = pkgs.mkShell rec {
+          pkgs,
+          lib,
+          selfPkgs,
+          ...
+        }:
+        let
+          mkWwwContent =
+            { domain }:
+            pkgs.stdenvNoCC.mkDerivation {
+              pname = "www-content";
+              version = domain;
+              src = ./.;
+
+              # Build dependencies
+              nativeBuildInputs = [
+                pkgs.hugo
+                pkgs.glibcLocales
+                (pkgs.python3.withPackages (python-pkgs: [
+                  python-pkgs.icalendar
+                  python-pkgs.pytz
+                ]))
+              ];
+
+              LOCALE_ARCHIVE = "${pkgs.glibcLocales}/lib/locale/locale-archive";
+
+              # Build phase - run Hugo to generate the site
+              buildPhase = ''
+                mkdir -p public
+                hugo --baseURL=https://${domain}/
+                
+                python3 ./tools/merge_cals.py
+                upcoming="$(python3 tools/gen_upcoming.py static/all.ics 20 5 | tr '\n' ' ')"
+                cp static/all.ics public/all.ics
+                sed -i "s#CALENDAR#$upcoming#g" public/index.html
+              '';
+
+              # Install phase - copy the public directory to the output
+              installPhase = ''
+                mkdir -p $out
+                cp -r public/* $out/
+              '';
+            };
+        in
+        {
+          production-content = mkWwwContent { domain = "berlin.ccc.de"; };
+          staging-content = mkWwwContent { domain = "staging.berlin.ccc.de"; };
+          local-content = mkWwwContent { domain = "localhost"; };
+        }
+      );
+
+      devShells = forAllSystems (
+        {
+          pkgs,
+          system,
+          selfPkgs,
+          ...
+        }:
+        {
+          default = pkgs.mkShellNoCC {
+            inputsFrom = [ selfPkgs.local-content ];
+
             packages = with pkgs; [
-              hugo
               go
-              (pkgs.python3.withPackages (python-pkgs: [
-                python-pkgs.icalendar
-                python-pkgs.pytz
-              ]))
+
               shellcheck
             ];
           };