It is a non-std rust library for serializing/deserializing ml-kem(aka kyber) public keys, encapsulating/decapsulating 256 bit ones and so on.
Current version of ml-kem crate used in this crate does not support rand crate of 0.9.x versions, so if everything doesn't work maybe you should downgrade the rand crate version to at least 0.8.5
Use generate_keypair{512/768/1024} to generate keypair, encapsulation key's functions to_bytes, from_bytes, encapsulate to do encapsulation, serialize and deserialize it. And decapsulate func of DecapsulationKey to decapsulate ciphertexts Here's an example below:
use qserde::*;
let mut rng = rand::thread_rng();
//generating ml_kem keypair of 1024-bit mode
let (dk, ek) = generate_keypair1024(&mut rng);
//encapsulation key deserialized into bytes
let serialized_encapsulaion_key = ek.to_bytes();
//converting bytes into 1024-bit mode encapsulation key
let ek = EncapsulationKey1024::from_bytes(&ek).unwrap();
//encapsulating random 32 bytes
let (ciphertext, shared_secret) = ek.encapsulate(&mut rng).unwrap();
//decapsulating shared secret from ciphertext
let another_shared_secret = dk.decapsulate(&ciphertext).unwrap();
assert_eq!(shared_secret, another_shared_secret);