# UltimaOS (uOS)

> A private, post-quantum encrypted personal workspace running entirely in your browser. Chat, mail, files, notes, documents, and kanban boards — all end-to-end encrypted with NIST-standardized post-quantum cryptography. No cookies, no tracking, no central password database. Hosted in the European Union.

UltimaOS (uOS) is a web-based personal operating system focused on privacy. Every message, file, note, and document is end-to-end encrypted in your browser. Private keys are derived deterministically from a 3-field login (name, phrase, email) and never leave your device — not even our servers can decrypt your data.

The platform is currently in invite-only early access and is free to use during the beta.

## Cryptography

uOS uses 100% post-quantum cryptography. There is zero classical asymmetric crypto in the codebase.

- **ML-DSA-65 (FIPS 204)** — digital signatures, 1952-byte public keys
- **ML-KEM-768 (FIPS 203)** — key encapsulation, 1184-byte public keys
- **XChaCha20-Poly1305** — symmetric authenticated encryption
- **HKDF-SHA256** — domain-separated key derivation
- **Argon2id** — password-derived material
- **AES-256-GCM** — local browser cache encryption (IndexedDB vault)

Communication is WebSocket-first: HTTP is used only for initial login. All other authenticated operations (chat messages, file transfers, board edits, mail) go through a signed WebSocket connection.

## Apps

- **uChat** — End-to-end encrypted messaging with markdown, attachments, voice notes, and per-conversation translation.
- **uMail** — Private email with encrypted storage.
- **uFiles** — Encrypted file storage with secure sharing (filenames are encrypted with the recipient's ML-KEM-768 key).
- **uNotes** — Private notes and rich-text documents.
- **uBoards** — Kanban-style task boards (cards, labels, assignees, due dates, comments, attachments).
- **uAI** — Bring-your-own AI assistant (OpenAI, Anthropic, local models). Conversations stay encrypted; the AI provider only sees what you explicitly send.
- **uStudio** — Build and publish your own websites and mini-apps inside uOS.
- **uBrowse** — Browse uStudio-published sites without leaving uOS.
- **uMarket** — Discover and install third-party mini-apps.

## Privacy guarantees

- No cookies, no tracking, no third-party analytics on app surfaces.
- No central password database. Identity is derived client-side from a 3-field login.
- Private keys never leave the browser; they are held only in volatile memory.
- Server only stores public keys and encrypted blobs.
- localStorage and sessionStorage are explicitly NEVER used — the app actively wipes all browser storage on boot.
- Hosted in the EU, GDPR compliant.

## Multi-platform architecture

Each user can create their own platforms (sub-accounts with separate app access and member lists). Examples: a personal "uOS" platform, a "My Company" work platform, a "Family" platform. Each platform has independent settings, members, and data scope. Users can be invited to other people's platforms as members.

## For organizations

uOS for Business deploys an isolated, fully encrypted workspace for your organization. Bring-your-own AI keys, no vendor lock-in, GDPR compliant, hosted in the EU.

Learn more: https://uos.sh/business/

## Try it

- Public landing page: https://uos.sh/
- For organizations: https://uos.sh/business/
- Public demo (no signup): https://uos.sh/demo/
- Request an invite: form on the landing page

## Status

- Closed beta (invite-only)
- Free during early access
- Web-only (Chrome, Firefox, Safari, Edge); a desktop tray agent is available for download

## What this site is NOT

- Not open source (proprietary; protected commercial codebase)
- Not advertising-supported (no ads, no tracking)
- Not federated (single-server architecture; data is encrypted, but the platform is hosted by UltimaOS)

## Contact

- General inquiries: form at https://uos.sh/
- Business inquiries: form at https://uos.sh/business/