Researchers have made a breakthrough in quantum-limited imaging by applying diffractive optical neural networks to estimate band-limited spatial-frequency amplitudes. This approach allows for the computation of precision limits using semidefinite programming to evaluate the Nagaoka-Hayashi Cramér-Rao bound, which is a fundamental limit on the precision of quantum parameter estimation1. The team has also introduced a novel measurement apparatus architecture that utilizes photon counting and saturates the precision limits, demonstrating the potential for significant advancements in imaging capabilities. This development has implications for various fields, including cryptography, where the increasing urgency of post-quantum cryptography planning is driven by the narrowing timeline of quantum developments. As a result, practitioners must prioritize planning for the migration to quantum-resistant cryptography to stay ahead of potential security threats, making this breakthrough a crucial consideration for those involved in cryptographic migration and quantum security.