The short version
You give us an email and (optionally) an Anki deck. We give you a tutor that remembers what you got wrong. Your conversation content is stored against your account and used to make your future sessions better — not to train models, not sold, not shared with advertisers. You can export your data and delete your account at any time.
What we collect
Account information
When you sign up, we collect your email address and (if you provide them) name and basic profile fields. Authentication is handled by Clerk, our identity provider. Clerk stores your login credentials; we store a stable user ID that links you to your data.
Conversation and learning data
When you use the tutor, we store the content of your sessions — your messages, the tutor's replies, the misconceptions caught, the topics covered, and your progress against the exam map. This is the substance of the product: it's what lets the tutor remember you across sessions and surface the right material at the right time.
Anki uploads
If you upload an Anki collection (either inside the app or via the free Anki Report tool), we store the .colpkg file and the data extracted from it (card text, deck names, review history) so the tutor can use it as backdrop and so we can generate your report.
Payment information
If you purchase a pass, payment is processed by Stripe. We never see or store your full card number or CVC. We do store a Stripe customer ID, the plan you bought, the purchase date, and your access expiration — enough to know what you paid for and when it ends.
Transactional email
We send you transactional emails — for example, "your Anki report is ready." These are sent via Amazon SES. We don't run a marketing newsletter, so you won't get promotional email from us by default.
Cookies and local storage
- Session cookies set by Clerk to keep you logged in.
- An identity cookie set when you use the public Anki Report tool, so we can show you your report later without an account.
- Analytics cookies (
_ga,_ga_*) set by Google Analytics 4 to measure aggregate site usage — page views, traffic sources, device type. Tied to a random ID, not to your account or identity.
We don't use advertising pixels or cross-site tracking. The GA4 setup is configured for measurement only — no Google Ads remarketing, no audience exports, no "Google products and services" data-sharing.
What we don't do
- We don't train shared AI models on your conversation content. The Anthropic API we use to power the tutor does not use API inputs for model training by default, and we don't opt in.
- We don't sell or rent your data. Ever.
- We don't share your data with advertisers or use it for retargeting.
- We don't run behavioral analytics tools like Facebook Pixel, Mixpanel, Hotjar, or session-replay services. We use Google Analytics 4 for aggregate measurement only (see above).
Who else touches your data (sub-processors)
We use a small set of third-party services to run the product. Each has its own privacy practices, which we vet before integrating:
| Service | What it does |
|---|---|
| Anthropic | Powers the tutor. Receives your messages and conversation context to generate replies. |
| Clerk | Authentication. Manages logins, sessions, and account-level identity. |
| Stripe | Payments. Processes card transactions and stores billing details we never see. |
| Amazon Web Services | Hosting, storage, and email. Includes DynamoDB (account + session data), S3 (file storage), CloudFront (CDN), and SES (transactional email). |
| Google Analytics | Aggregate site measurement. Receives page-view events and basic device/referrer info — never your account details or conversation content. |
How long we keep your data
We keep your account data and learning history for as long as your account is active. If you delete your account, we delete your personal data within 30 days, except where we're legally required to keep records (for example, payment receipts retained for tax and accounting purposes).
Backups may persist for an additional 90 days after deletion, after which they roll off automatically.
Your rights
You can:
- Access your data — your conversation history, gaps, and Anki cards are visible inside the app.
- Export your misconception cards as a standard
.apkgfile at any time. - Delete your account by emailing hello@lacunos.com with the subject "Delete my account." We confirm by reply and wipe your data on the timeline above. An in-app delete button is coming; until then, email is the route.
- Ask questions by emailing hello@lacunos.com. If you're in the EU/UK or California, you have additional rights under GDPR and CCPA; email us and we'll honor them.
International users
Our servers and sub-processors are based primarily in the United States. If you use lacunos from outside the US, your data will be transferred to and processed in the US. We rely on the standard contractual clauses with our sub-processors for international transfers where required.
Children
lacunos is built for adults studying for US biomedical exams (MCAT and USMLE Step 1). It's not intended for children under 13, and we don't knowingly collect data from them.
Changes to this policy
If we make material changes, we'll update the "Effective" date at the top and — if the change affects how we handle existing data — notify you by email before the change takes effect.
Contact
For any privacy question, including data access, deletion, or correction requests, email hello@lacunos.com.