Private-server encrypted messenger
A messaging platform for employees that runs on the institution’s own servers. Messages are encrypted on the sender’s device and decrypted only on the recipient’s. Neither the server nor the admin panel can read them.
- Can you send the photo of the new building? 14.02
-
This is how it looks now. 14.03 - 0:14 14.04
- Q3-deck.pdf2,4 MB · PDF 14.05
- Great. Meeting tomorrow at 2 pm, 3rd floor. 14.06
What we built
- Signal protocol design (X3DH, Double Ratchet, Sender Key) with one wire format across Swift, Kotlin and TypeScript
- Clients for iOS, iPadOS, macOS, watchOS, Android and the web
- Active Directory sign-in; an account closed in AD closes here within the hour
- Admin panel that cannot read content, sealed audit log, SIEM export
- Content-free push: the phone is only woken up
Who sees what
| What the server sees | What the server never sees |
|---|---|
| Who wrote to whom, and when | Message text |
| Size of the encrypted envelope | Files and photos sent |
| Registered devices | Decryption keys |