After reading Curtin docs it seemed possible to roll out system with full disk encryption via MAAS. Curtin supports that through dm-crypt.
I have been trying to achieve that in past few days, but all in vain ;-(. Any help, nudge to right direction would be appreciated.
PS running MAAS version: 2.4.2 (7034-g2f5deb8b8-0ubuntu1) and Curtin version: 18.1-17-gae48e86f-0ubuntu1~18.04.1. Deploy node is Ubuntu 18.04.