How to Test Caching in Vibecoded Apps

Check response headers for every important resource using DevTools Network tab. Static assets (images, CSS, JS) should have long Cache-Control max-age values with unique filenames that change on deploy (cache busting). API responses should have appropriate caching — public data can be cached briefly, but user-specific data should include Cache-Control: no-store or short max-age values.

Test cache behavior by deploying an update and verifying that users see the new version without a hard refresh. AI-generated apps often cache the main HTML file, causing users to load old JavaScript bundles that do not match the new API. Verify that index.html has Cache-Control: no-cache so the browser always checks for updates, while hashed asset files can be cached indefinitely.

If your app uses client-side caching (React Query, SWR, Apollo cache), test that data updates are reflected across the app. Update a record through the API and verify the cached version updates on the next request. AI-generated caching configurations often cache data forever without revalidation, showing users stale information indefinitely.

Test cache invalidation after mutations. When a user creates, updates, or deletes a record, related cached queries should be invalidated or updated. For example, after creating a new item, the items list should include the new item without requiring a page refresh. Many vibecoded apps require the user to manually refresh to see their own changes.

If your app uses a CDN like Cloudflare or Vercel Edge, test that cache purging works after deployment. Access your app from different geographic locations (using a VPN) and verify content consistency. CDN caches can serve stale content for hours if purging is not configured correctly after deploys.

If your app registers a service worker, test its caching strategy carefully. Navigate offline and verify that cached pages work. Then go back online and verify the service worker fetches updates. AI-generated service workers often use cache-first strategies that prevent users from ever seeing updates. Test the update flow: deploy a change, verify the service worker detects the update, and confirm the user sees fresh content.