Privacy Policy

Summary

Sylvarium is designed to keep your data yours. No accounts. No tracking. No advertising. Your vocabulary and books live in your browser — not on our server.

What we store on your device

The following is stored locally in your browser using IndexedDB and localStorage, and never transmitted to our server:

• Words you have looked up, along with example sentences, references, and revision history
• Books you have added, including title, author, reading status, and library loan dates
• App preferences such as colour theme and display settings

You can export all this data as a JSON file, import it on another device, or delete it at any time from the Settings page.

What leaves your device

Three types of request are sent externally when you use specific features:

• Word lookups — the word you search for is sent to the Wiktionary API, operated by the Wikimedia Foundation. This also covers pronunciation, etymology, synonyms and antonyms.
• ISBN lookups — when you scan a book barcode or enter an ISBN manually, the ISBN is sent to the Open Library API, operated by the Internet Archive.
• Photos for text extraction or barcode scanning — images you choose are uploaded to our server, processed in memory by local software (Tesseract OCR / pyzbar), and immediately discarded. No image is stored on disk.

We do not control the privacy practices of Wikimedia or the Internet Archive. Please review their privacy policies via the links above.

Server-side data

Our server keeps a rolling 30-day count of API requests made (e.g. "42 word lookups on this date"). This contains no personal information — no words, no user identifiers, no IP addresses.

Rate limiting is applied per IP address to prevent abuse. This is held in memory only and is never written to disk or logs.

Cookies and local storage

Sylvarium uses no cookies. Browser localStorage is used to remember your preferences (colour theme, display settings). This data never leaves your device.

Third parties

No third-party analytics, advertising, or tracking scripts are loaded. All fonts are served directly from our server.

Your rights

Because no personal data is held on our server, there is nothing for us to delete or provide on request. All your data is in your own browser — you are in full control. You can delete everything from Settings → Danger Zone.

Contact

Questions about this policy? Email the developer.