What is crypto-agility?
Crypto-agility is the ability to change the cryptographic algorithms a system uses without rewriting or replacing the system. In practice it means that algorithms are chosen by configuration, not hard-coded; software uses maintained libraries that receive new algorithms through updates; certificates and keys are managed centrally, with known owners and expiry dates; and you know where each algorithm is used. It matters now because the post-quantum transition will not be the last one: HQC and FN-DSA are still coming, parameters may be revised, and a flaw could appear in a young implementation. An organisation that makes one painful, manual migration will face the same pain next time; one that builds agility turns the next change into a configuration release. Ask about it in every purchase: can the product change its key-exchange and signature algorithms by update or setting, and does the vendor commit to doing so? A product that cannot is a migration problem you are buying today.