Prekey Bundles: How Encrypted Chat Works When You're Offline
How prekey bundles let encrypted chat work when the recipient is offline: what they contain, how a sender derives a shared secret alone, and the key-substitution risk.
X3DH, Explained: The Handshake Behind Asynchronous Encryption
How X3DH lets two people share an encryption key when one is offline — the four Diffie-Hellman operations, what each provides, and the post-quantum upgrade.
Harvest Now, Decrypt Later: Why Post-Quantum Encryption Already Matters
An adversary who records your encrypted traffic today can wait years to decrypt it. Why long-lived secrets need post-quantum protection now, and how hybrid X25519 + ML-KEM-768 delivers it.
What Is the Double Ratchet? Forward Secrecy, Explained
A beginner-friendly but technically correct explainer of the Double Ratchet: forward secrecy, break-in recovery, why deleting keys matters, and how RVNT uses it.