Aster builds end-to-end encrypted email that keeps your communication private and free from censorship.
- Aster Mail - quantum-safe, end-to-end encrypted email
- Aster Authenticator - end-to-end encrypted two-factor authentication app, in development
Aster's application code is open source under AGPL v3. If you find a problem, open an issue. If you want to fix one, open a pull request.
All encryption and decryption happens on your device. Mail between Aster accounts uses a Signal-inspired protocol (X3DH and Double Ratchet) with ML-KEM-768 post-quantum cryptography, which protects against store-now-decrypt-later attacks. Mail to external recipients uses Ed25519 OpenPGP with Curve25519 encryption subkeys, portable keys that work with any OpenPGP client.
Aster encrypts as much metadata as possible, including:
- Subject lines
- Contacts
- Folder structure
- Search indices
- Timestamps
- Attachment data
We welcome feedback and contributions of all kinds. Read our contributing guide and code of conduct to get started.
