Luksy implements encryption and decryption using LUKSv1 and LUKSv2 formats. Think of it as a clunkier cousin of gzip/bzip2/xz that doesn't actually produce smaller output than input, but it encrypts, and that's nice.

The main goal is to be able to encrypt/decrypt without the Linux device mapper. Duplicating functions of cryptsetup that it can perform without accessing the Linux device mapper is not a priority.

If you can cryptsetup, you should use that instead.