Post quantum cryptography is no longer something security teams can leave entirely to research departments. NIST finalized ML-KEM as a post quantum key encapsulation mechanism in 2024, and the IETF is actively standardizing hybrid key agreement for TLS 1.3. The practical transition is already visible in modern TLS implementations and large internet infrastructure. For engineering teams, however, the important question is not simply what ML-KEM does. The bigger question is what actually change...