Security · On-device by architecture
Audio never leaves your Mac.
Sussur is not “encrypted in transit” theater. The speech-to-text runs locally on your Mac. The LLM key is yours. The transcripts and persona memory live in SQLite on your laptop. Here is the literal data path.
01 · Source
Your microphone + the meeting app
Zoom, Google Meet, Microsoft Teams, FaceTime, a regular phone call on the desk. Sussur does not need to join the call as a bot.
02 · Capture
macOS ScreenCaptureKit
Native Apple framework. Captures both sides of any audio source on the Mac. Requires explicit user permission. No third-party kernel extension. No bot joining the meeting.
03 · Transcription
NVIDIA Parakeet TDT v3 · on-device
Open-weights speech-to-text model running on the user's Mac via sherpa-onnx. Sub-200ms latency. Audio bytes are processed in-memory and never persisted to disk by default. Apple SpeechAnalyzer is a viable replacement; we currently prefer Parakeet for accuracy on phone-audio bandwidth.
04 · Coaching
Your own API key — or nothing at all
Transcript text goes to the AI provider you configured, on an OpenRouter API key you supply and hold. The request does not pass through Sussur: there is no gateway, no account and no server of ours in the path. Only text leaves the device — never audio, never video, and never a facial or vocal signal, because Sussur derives none. Point it at a model running under Ollama on the same Mac and the coaching step stays local too.
05 · Storage
SQLite + LanceDB · on your Mac
Transcripts, summaries, persona memory, rapport time series: all stored locally in encrypted SQLite + LanceDB. Nothing ships to Sussur servers. Your call history is portable; you can export the SQLite file at any time.
Four pillars
What we mean by “privacy by architecture.”
- On-device by architecture
- Not a feature, an architectural decision baked in from the first commit. Sussur was built around sherpa-onnx and Parakeet from day one. Retrofitting on-device into a cloud meeting tool takes a rewrite, not a release.
- EU AI Act Article 50 ready
- Article 50 transparency obligations land 2 Aug 2026. Annex III high-risk classification does not apply (Sussur coaches the user of the device, not third parties), but the transparency obligations do. We publish them in plain language and provide the disclosure templates business customers need.
- GDPR
- Privacy Policy + DPA published. Minimal data because your audio and video never leave the device.
- SOC 2 readiness assessment underway
- Type II attestation on the roadmap. Not shipping a claim we cannot substantiate.
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