diff --git a/hosts/fw/pkgs/foundry-vtt/FoundryVTT-Node-13.350.zip b/hosts/fw/pkgs/foundry-vtt/FoundryVTT-Node-13.350.zip
deleted file mode 100644
index 3f7ae62..0000000
Binary files a/hosts/fw/pkgs/foundry-vtt/FoundryVTT-Node-13.350.zip and /dev/null differ
diff --git a/hosts/fw/pkgs/foundry-vtt/default.nix b/hosts/fw/pkgs/foundry-vtt/default.nix
index c07714e..febf95d 100644
--- a/hosts/fw/pkgs/foundry-vtt/default.nix
+++ b/hosts/fw/pkgs/foundry-vtt/default.nix
@@ -1,10 +1,13 @@
-{ stdenv, lib, unzip }:
+{ stdenv, lib, fetchurl, unzip }:
 
 stdenv.mkDerivation rec {
   pname = "foundry-vtt";
   version = "13.350";
 
-  src = ./FoundryVTT-Node-13.350.zip;
+  src = fetchurl {
+    url = "https://feeds.cloonar.com/FoundryVTT-Node-${version}.zip";
+    hash = "sha256-r7tUdUNd2SneqqLJYgiElnnZJm94fhKcAQPVyo2zc8o=";
+  };
 
   nativeBuildInputs = [ unzip ];
 
diff --git a/hosts/fw/pkgs/foundry-vtt/update.sh b/hosts/fw/pkgs/foundry-vtt/update.sh
new file mode 100755
index 0000000..470b03c
--- /dev/null
+++ b/hosts/fw/pkgs/foundry-vtt/update.sh
@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+# Usage: ./update.sh <version>
+# Example: ./update.sh 13.351
+#
+# Before running, upload the new zip to feeds.cloonar.com:
+#   FoundryVTT-Node-<version>.zip
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+DEFAULT_NIX="$SCRIPT_DIR/default.nix"
+
+if [[ $# -ne 1 ]]; then
+  echo "Usage: $0 <version>" >&2
+  echo "Example: $0 13.351" >&2
+  exit 1
+fi
+
+NEW_VERSION="$1"
+URL="https://feeds.cloonar.com/FoundryVTT-Node-${NEW_VERSION}.zip"
+
+echo "Fetching hash for $URL..."
+RAW_HASH=$(nix-prefetch-url "$URL")
+SRI_HASH=$(nix hash to-sri --type sha256 "$RAW_HASH")
+
+echo "Version: $NEW_VERSION"
+echo "Hash: $SRI_HASH"
+
+sed -i "s|version = \".*\"|version = \"${NEW_VERSION}\"|" "$DEFAULT_NIX"
+sed -i "s|hash = \".*\"|hash = \"${SRI_HASH}\"|" "$DEFAULT_NIX"
+
+echo "Updated $DEFAULT_NIX"
+echo "Verifying build..."
+nix-build -E "with import <nixpkgs> {}; callPackage $DEFAULT_NIX {}"
+echo "Build successful!"