Tomb: File Encryption on GNU/Linux

Tomb consists of a simple shell script (Zsh) using standard filesystem tools (GNU) and the cryptographic API of the Linux kernel (cryptsetup and LUKS).

This looks really interesting.

What encryption modes does it use?

Specifically, does it use xts? If so does it have to? https://sockpuppet.org/blog/2014/04/30/you-dont-want-xts/