Built for long-form work chat — not a system assistant. TeeChat is designed so your chat history stays on your devices — not in our cloud. Download macOS Apple Silicon or Windows today from the download page — Linux and Intel Mac are rolling out. Local folders, Deck Studio, and optional local models. Use the web preview at https://chat.teechat.ai for hosted AI with encrypted envelopes to attested engines today. OPE and our inference engine are open source.
Hosted chat in the browser at chat.teechat.ai — threads stay on this device in IndexedDB and auto-delete after 7 days (no server-side archive), with encrypted envelopes to engines and attestation verification in Settings. Mobile apps are still in development.
We do not operate a server-side archive of your conversations. On the web preview, threads stay in this browser and auto-delete after 7 days (not synced across devices); desktop apps store Markdown in folders you choose. Hosted inference sends opaque encrypted envelopes — the gateway sees ciphertext only. An open-source inference engine inside a TEE decrypts for the model; verify its attestation in Settings before sending.
macOS Apple Silicon and Windows are available now — local-first folders you control, Deck Studio, optional local models, and the full feature set. Linux and Intel Mac builds are rolling out on the download page.
Native iOS and Android apps are in development — same local folder model and encrypted hosted path as desktop and web. Sign up on web now to keep one account when mobile ships.
How hosted AI works
Data sovereignty does not mean no cloud — it means your chat history stays yours. When you connect to teechat.ai, messages are encrypted before they leave your device; the gateway routes opaque envelopes and is not designed to persist plaintext. Someone must decrypt to run the model: a dedicated open-source inference engine, inside a measured TEE, does — not the gateway or a generic ops login. When a client or security review asks for evidence, verify attestation in Settings and audit OPE and the engine on GitHub.
Your chat threads live in folders you choose — you rule, you can export, and canceling Pro does not delete your local archive. TeeChat does not operate a server-side chat archive. Using hosted AI on teechat.ai is optional; when you do, messages leave as encrypted envelopes and the routing server forwards scrambled text only. When a review asks for proof, verify the engine in Settings (L3).
On web today, chats stay in this browser only (IndexedDB) and auto-delete after 7 days — we do not operate a server-side archive. Signing in does not extend retention or sync threads to other devices; clearing browser data removes them immediately. Desktop apps store threads in folders you choose (for example ~/TeeChat on macOS and Windows). Mobile apps are in development.
Your client encrypts before send. The gateway forwards ciphertext only. A dedicated open-source inference engine inside a TEE decrypts to run the model.
Apple PCC protects assistant requests in Apple’s ecosystem. TeeChat is work chat: you own the thread files, use Expert and Research, and can verify engine attestation plus audit OPE on GitHub when questionnaires ask for evidence — not confidence alone.
Offer artifacts: confidential mode, Verify in Settings, trust evidence you can record, and links to open-source OPE and the inference engine.
The Windows installer is Authenticode-signed (publisher: Weiji Guo, TeeChat founder). Signing proves who built the file. Microsoft Defender SmartScreen is separate: it also checks reputation for new publishers and new file hashes. Until TeeChat accumulates enough trusted installs, SmartScreen may show a blue “Windows protected your PC” screen even though the app is signed. Click More info, then Run anyway — or verify the publisher name matches before continuing. Reputation improves over time; we are not hiding an unsigned build.
Open standard
Open Privacy Envelope (OPE) is the open-source encryption layer behind TeeChat's hosted path — envelope format, hybrid E2E crypto, attestation hooks, and reference implementations. It is evidence for L3 verification, not a substitute for owning your local folder.