Anyhide v0.14 Adopts Post-Quantum Hybrid Encryption with Dual Migration Strategy

The Anyhide project has migrated to post-quantum hybrid encryption in version 0.14, implementing ML-KEM-768, which became a NIST standard (FIPS 203) in 2024. The primary motivation was the 'harvest-now-decrypt-later' threat, where adversaries could record encrypted traffic today and decrypt it once quantum computers mature — a real risk given that Anyhide codes are persistent and long-lived. The project's two cryptographic subsystems required opposite migration approaches: existing codes needed backward compatibility so older classical keys kept working, while the RAM-only chat protocol could simply break with the old format since no historical data persists. For codes, a 5-byte magic prefix was introduced to distinguish new hybrid-format payloads from legacy classical ones, allowing the decoder to route each ciphertext to the correct decryption layer without errors. The approach was made safer by Anyhide's existing 'never-fail' decoder design, which returns deterministic garbage on bad input rather than throwing errors that could be probed by attackers.