added option for global and per profile pkg and zip installs

modules/archive-installs.nix

@@ -0,0 +1,41 @@
+{ pkgs, lib, ... }:
+
+let
+  cfg = config.archiveApps;
+  stampDir = "/usr/local/share/nix-pkg-stamps";
+
+  appScript = a:
+    let
+      src = pkgs.fetchurl { inherit (a) url sha256; };
+    in ''
+      stamp="${stampDir}/${a.name}"
+      want="${src}"
+      if [ "$(cat "$stamp" 2>/dev/null)" != "$want" ]; then
+        echo "installing ${a.name}..."
+        tmp=$(mktemp -d)
+        if /usr/bin/unzip -q "$want" -d "$tmp"; then
+          if [ -d "$tmp/${a.app}" ]; then
+            rm -rf "/Applications/${a.app}"
+            /usr/bin/ditto "$tmp/${a.app}" "/Applications/${a.app}"
+            mkdir -p "${stampDir}"
+            echo "$want" > "$stamp"
+          else
+            echo "${a.name}: ${a.app} not found in zip, skipping"
+          fi
+        else
+          echo "${a.name}: could not unzip, skipping"
+        fi
+        rm -rf "$tmp"
+      fi
+    '';
+in
+{
+  optiosn.archiveApps = lib.mkOption {
+    type = lib.types.typesOf (lib.types.attrsOf lib.types.str);
+    default = [ ];
+    description = "Apps distributed as .zip archives to install into /Applications";
+  }
+
+  system.activationScripts.postActivation.text =
+    lib.concatMapStringsSep "\n" appScript cfg;
+}