Package kyber implements the CRYSTALS-Kyber.CPAPKE public key encryption as submitted to round 3 of the NIST PQC competition and described in https://pq-crystals.org/kyber/data/kyber-specification-round3.pdf The related key encapsulation mechanism (KEM) CRYSTALS-Kyber.CCAKEM can be found in the package github.com/cloudflare/circl/kem/kyber.