@gdinwiddie Probably your browser's LocalStorage. Based on their FAQ and architecture docs, Uruky achieves personalization through explicit user-configured rules, not behavioral tracking. Here's how it breaks down:

What they don't store:
- No search query logs
- No click history
- No behavioral profiles
- No email or name — just an anonymous account number (like Mullvad VPN)

What they do store (for personalization):
- Your domain preferences: You manually boost, lower, or exclude specific domains (e.g., block `pinterest.com`, boost `marginalia-search.com`)
- TLD preferences: You can filter out entire top-level domains (e.g., `.buzz`, `.fun`, `.lol`)
- Provider ranking: You pick and order which search providers to query (Mojeek, Marginalia, Serper, etc.)
- Session metadata: Country and device type, retained up to 30 days (for rate limiting and abuse prevention)

So "personalization without tracking" is technically honest, but it's really **customization** — the user does the work, not the machine learning.