diff --git a/package-lock.json b/package-lock.json
index bcde33d..248d735 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "instaarchive-viewer",
-  "version": "1.6.1",
+  "version": "1.6.2",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "instaarchive-viewer",
-      "version": "1.6.1",
+      "version": "1.6.2",
       "dependencies": {
         "@tailwindcss/vite": "^4.1.14",
         "@vitejs/plugin-react": "^5.0.4",
diff --git a/package.json b/package.json
index 4c77021..a157903 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "instaarchive-viewer",
   "private": true,
-  "version": "1.6.1",
+  "version": "1.6.2",
   "type": "module",
   "scripts": {
     "dev": "vite --port=3000 --host=0.0.0.0",
diff --git a/src/App.tsx b/src/App.tsx
index 23cdd05..ec918c0 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -632,7 +632,7 @@ export default function App() {
       {!isScanning && (
         <footer className="max-w-5xl mx-auto px-4 py-12 text-center text-xs text-gray-400 space-y-4 text-black">
           <div className="flex flex-wrap justify-center gap-x-4 gap-y-2 uppercase tracking-tight text-black"><span>Meta</span><span>About</span><span>Blog</span><span>Jobs</span><span>Help</span><span>API</span><span>Privacy</span><span>Terms</span><span>Locations</span><span>Instagram Lite</span><span>Threads</span><span>Contact Uploading & Non-Users</span><span>Meta Verified</span></div>
-          <div className="text-black/40 text-black">© 2026 InstaArchive Viewer</div>
+          <div className="text-black/40 text-black">© 2026 InstaArchive Viewer · v{__APP_VERSION__}</div>
         </footer>
       )}
     </div>
diff --git a/src/main.tsx b/src/main.tsx
index b1e7fbf..4990a4f 100644
--- a/src/main.tsx
+++ b/src/main.tsx
@@ -14,7 +14,7 @@ const updateSW = registerSW({
       setInterval(() => {
         r.update();
       }, 60 * 60 * 1000);
-      console.log('[PWA] Service Worker registered and update interval set.');
+      console.log(`[PWA] v${__APP_VERSION__} registered; hourly update checks enabled.`);
     }
   },
   onNeedRefresh() {
diff --git a/src/types/globals.d.ts b/src/types/globals.d.ts
new file mode 100644
index 0000000..ead0908
--- /dev/null
+++ b/src/types/globals.d.ts
@@ -0,0 +1,9 @@
+/**
+ * Build-time constants.
+ *
+ * This file deliberately has no imports or exports: that keeps it an ambient
+ * script rather than a module, so the declarations below are global.
+ */
+
+/** Release version, injected by `define` in vite.config.ts. */
+declare const __APP_VERSION__: string;
diff --git a/vite.config.ts b/vite.config.ts
index 3e2fcfa..78c9506 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -3,9 +3,24 @@ import react from '@vitejs/plugin-react';
 import path from 'path';
 import {defineConfig} from 'vite';
 import { VitePWA } from 'vite-plugin-pwa';
+import { createRequire } from 'module';
+
+const { version } = createRequire(import.meta.url)('./package.json');
 
 export default defineConfig(() => {
   return {
+    /**
+     * The release version, compiled into the client.
+     *
+     * This is load-bearing, not cosmetic. The service worker precaches
+     * index.html *including its response headers*, so a server-side header
+     * change (a CSP fix, say) never reaches an installed PWA: nothing in the
+     * client build changed, the precache manifest is byte-identical, and the
+     * worker has no reason to update. Baking the version in means every release
+     * changes the bundle hash, which changes index.html, which invalidates the
+     * precache and re-fetches the shell with current headers.
+     */
+    define: { __APP_VERSION__: JSON.stringify(version) },
     plugins: [
       react(), 
       tailwindcss(),