From the github page:
“Arnika is a compact, lightweight external extension for Wireguard VPN, engineered to incorporate symmetric keys as Pre-Shared Keys (PSK) into Wireguard. This integration ensures the establishment of a quantum-secure VPN (safeguarding against compromise of session keys).

It gathers a 256-bit symmetric encryption key from a Key Management System (KMS) within a Quantum Key Distribution (QKD) infrastructure, shares the associated key ID with an Arnika peer, and configures an additional Pre-Shared Key (PSK) for Wireguard using the obtained key material.

Arnika offers an additional security layer for cryptography enthusiasts. It can integrate Post-Quantum Cryptography (PQC) by leveraging a PQC key provided by a system like Rosenpass. This key is then used to create an even stronger Preshared Key (PSK) for WireGuard. This PSK benefits from both PQC and QKD, offering enhanced protection against potential security threats. […]”