Privacy Notice

Last updated: May 27, 2026

This notice explains what personal information DET DUDE (“we”, “us”) collects from you, why we collect it, who we share it with, and how you can exercise your rights. We try to keep it short and plain.

1. Who we are

DET DUDE provides AI-graded mock tests, drills, and live coaching for the Duolingo English Test. We are not affiliated with, endorsed by, or sponsored by Duolingo, Inc.

Questions about this notice or your data: privacy@detdude.com.

2. Information we collect

Account data — email, name, hashed password, the OAuth provider you signed in with (Google / LinkedIn), and any profile fields you fill in (region, target score, timezone).
Usage data — mock-test answers, written and spoken responses, drill activity, streaks, scores, and feature interactions. This is the substance of what we grade and what powers the recommendations on your dashboard.
Audio recordings — your speaking-task audio is stored only as long as needed to grade and let you review it, then deleted on schedule.
Payment data — handled entirely by Stripe; we receive only the customer ID, subscription status, and last-4 digits of the card. We never see or store full card numbers.
Technical data — IP address, browser/device info, and error logs collected by the site to keep it secure and working.

3. How we use it

To deliver the service: score your responses, save your progress, run group classes, send transactional emails (e.g. verify your email, password reset, payment receipts).
To improve the product, including model evaluation. We do not sell your data and do not use it to train third-party foundation models without a separate, explicit opt-in.
To prevent fraud, abuse, and security incidents.
To comply with legal obligations.

4. Who we share it with (sub-processors)

We use trusted infrastructure providers; each receives only the data needed for its function and is contractually bound to confidentiality.

Vercel — site hosting (US).
Railway — API hosting (US).
Neon — Postgres database (US).
Cloudflare R2 — audio file storage.
Stripe — payment processing.
Anthropic (Claude) & OpenAI (Whisper) — AI grading and transcription. Per their API terms, your inputs are not used to train their models.
Resend — transactional email delivery.
Sentry — error monitoring (only if enabled).
PostHog — product analytics (only if you accept analytics cookies).
LiveKit — live-class audio/video routing.

5. Cookies

Essential cookies keep you signed in and remember your consent choice. They are always on — the site doesn't work without them.

Analytics cookies (PostHog) help us see which features are used and where people get stuck. They run only after you choose “Accept all” in the cookie banner. You can withdraw consent at any time by clearing site data in your browser.

6. Your rights

Wherever you live, you can email privacy@detdude.com to:

Access a copy of your data.
Correct inaccurate data.
Delete your account and associated data.
Export your data in a portable format.
Object to or restrict processing.
Withdraw consent for analytics at any time.

EU/UK residents have the additional rights described in the GDPR/UK GDPR. California residents have the rights described in the CCPA/CPRA. We do not sell personal information.

7. Data retention

We keep your account and content while your account is active. When you delete your account we erase or anonymize your data within 30 days, except records we must keep for legal or accounting reasons (e.g. invoices) for up to 7 years.

8. International transfers

Our infrastructure is primarily hosted in the United States. If you access the service from outside the US, you understand that your data may be processed there under appropriate safeguards.

9. Children

The service is intended for users aged 16 and over. We do not knowingly collect data from anyone under 16. If you believe a minor under 16 has provided us with personal data, contact us and we will delete it.

10. Changes

We will post the new version here with an updated “Last updated” date. Material changes will be announced by email to active subscribers.