NIST Post-Quantum Cryptography Standards and pyca/cryptography Implementation
The US government is mandating a transition to Post-Quantum Cryptography (PQC) to mitigate "Harvest Now, Decrypt Later" (HNDL) threats from future large-scale quantum computers capable of breaking RSA and ECC. Driven by recent Executive Orders, the migration requires implementing NIST-standardized algorithms, specifically FIPS 203 (ML-KEM), FIPS 204 (ML-DSA), and FIPS 205 (SLH-DSA). This shift is not a drop-in replacement; it introduces significant data overhead in key and signature sizes. Implementation is surfacing in critical low-level libraries like pyca/cryptography (v48), which utilizes Rust bindings and AWS-LC to support these new primitives, impacting over 1.2 billion monthly downloads across critical infrastructure tools like Ansible and Certbot.