Privacy Policy
Last updated: April 7, 2026

Stack Spy is operated by Sylvain Charnet. This policy explains what data the Stack Spy Chrome extension and website collect, how it is used, and your rights.

1. What data the Chrome extension collects
   When you click the Stack Spy icon on a website, the extension:

Domain name — the hostname of the page you chose to scan (e.g. example.com) is sent to our server and stored to generate the public stack page.
Detected technologies — the list of technologies identified on that page (e.g. "React", "Cloudflare") is stored and displayed publicly at stack-spy.com/companies/[domain].
Social media profile URLs — public profile links found in the page source (LinkedIn, GitHub, etc.) are stored alongside the stack.
Authentication token — if you sign in, a JWT is stored locally in chrome.storage.local on your device only. It is never transmitted except to authenticate API requests.
The extension does not collect passwords, payment information, health data, precise location, browsing history beyond scanned domains, or any keystrokes/mouse movements.

HTTP response headers and raw HTML are analyzed locally in the browser and are never transmitted to our servers.

1. What data the website collects
   Account data — if you create an account, we store your email address to authenticate you.
   Server logs — standard web server logs (IP address, timestamp, URL requested) are retained for up to 30 days for security and debugging.
   Cookies — a session cookie is set when you sign in. No third-party tracking cookies are used.
2. How we use your data
   To generate and display public tech stack pages at /companies/[domain]
   To allow searching indexed sites by technology or category
   To authenticate your account if you choose to sign in
   To ensure the security and stability of the service
   We do not sell, rent, or share your personal data with third parties. We do not use your data for advertising, credit scoring, or any purpose unrelated to the tech detection service.
3. Public data
   Tech stack pages (domain + detected technologies) are publicly accessible by design — this is the core feature of Stack Spy. If you scan a website, its stack page may be indexed by search engines. You can request deletion by contacting us.
4. Data retention
   Scan results are stored indefinitely to maintain the public directory.
   Account data is deleted within 30 days of account closure upon request.
   Server logs are deleted after 30 days.
5. Your rights
   You may request access to, correction of, or deletion of any personal data we hold about you by emailing privacy@stack-spy.com. We will respond within 30 days.
6. Changes to this policy
   We may update this policy as the product evolves. The "Last updated" date at the top will reflect any changes. Continued use of the extension or website after changes constitutes acceptance.
7. Contact
   Questions? Email privacy@stack-spy.com