What leaves your Mac, and what doesn't.
A dictation app hears everything you say. This page sets out exactly where that goes, how it is protected, and where the protection stops.
Local by default.
Transcription, cleanup, and Vault storage run on your Mac. In Local Only mode nothing leaves; in Balanced mode on Turbo, only explicit query excerpts, anonymized search strings, or selected screen regions are sent.
| Data | Leaves your Mac? | Detail |
|---|---|---|
| Microphone & meeting audio | Never | Transcribed on your Mac by Parakeet-TDT and Whisper Large Turbo + SpeakerKit. Never uploaded. |
| Vault notes & search index | Never | Stored in vault.enc (SQLCipher AES-256) on your Mac. |
| Atlas imported files | Never | Stored in atlas/<sha256>.blob (AES-GCM 1 MB chunks) on your Mac. |
| Vault & Atlas encryption keys | Never | 256-bit master key held in your macOS Keychain; Atlas key derived via HKDF. |
| Cleanup & Local Only reasoning | Never | S1-mini and Loom 3B run on a loopback-only server inside the app. |
| Ask Tyne / Ask Atlas excerpts | Opt-in | Balanced mode on Turbo only: bounded text passages (~2k–6k tokens) go through our zero-retention llm-router gateway to Cerebras Qwen 3.8 27B. Never sent in Local Only mode. |
| Circle to Search region | Opt-in | Balanced mode on Turbo only when you press Ask: cropped selection JPEG + local OCR text go to llm-router vision. Password and private windows are blocked. |
| Anonymized web search query | Opt-in | Balanced mode on Turbo only: stripped public query goes to brave-cerebras-search (Brave Search + Cerebras synthesis). |
One encrypted file.
Threads, notes, entity facts and full-text indexes share a single SQLCipher database. We never receive the key, so we cannot read the vault or recover it.
- Database
- SQLCipher via GRDB (vault.enc)
- Atlas file storage
- AES-GCM 1 MB chunks (atlas/<sha256>.blob)
- Key
- 256-bit random master key + HKDF per Mac
- Key storage
- macOS Keychain (in.tyne.desktop)
- Key derivation
- 256,000 PBKDF2 iterations + CryptoKit HKDF
- Memory security
- Enabled
- File permissions
- folder 0700 · vault.enc 0600
Guards on the paste.
Tyne inserts text through the pasteboard and a synthetic ⌘V. These checks run before every insertion.
No pasting into password fields
If the focused field is a secure text field, Tyne copies the text to your clipboard instead of inserting it.
No pasting while you hold a modifier
Holding Shift, Control or Option while text is ready turns a paste into a copy, so a stray shortcut cannot fire.
Credentials stripped before storage or egress
Key and token shapes, such as API keys, JWTs and private keys, are redacted before text is indexed, written, or included in a cloud prompt.
Stateless cloud gateway & hard token caps
Our Supabase Edge Functions (llm-router and brave-cerebras-search) validate your JWT, reserve aggregate token counts atomically, and never write prompts, completions, or images to database tables.
Where it stops.
- Redaction uses pattern matching. It cannot catch every secret, especially one that is misheard or spelled out. Don’t dictate credentials.
- Tyne is not App-Sandboxed. Typing into other apps needs the Accessibility API, which the sandbox blocks, so Tyne ships with Developer ID signing and notarization instead.
- The vault key is readable after your Mac’s first unlock following a restart. Anyone who can use your unlocked Mac account can use Tyne.
- In Balanced mode on Turbo, Tyne’s own gateway stores zero prompt or image content, while upstream inference (Cerebras) and search (Brave) process requests under their API terms. Use Local Only mode when strict air-gapped processing is required.
- Backups, such as Time Machine, copy vault.enc and atlas/*.blob in their encrypted form. Deleting the in.tyne.desktop Keychain item makes those encrypted files permanently unrecoverable.
Report a vulnerability
Email security@tyne.in with steps to reproduce. Please give us a chance to fix it before disclosing publicly.