The Wiretrustee carrier board utilises the power of the Raspberry Pi Compute Module 4 as network-attached storage (NAS). The carrier board supports up to four HDDs or SSDs and features physical ports that the Compute Module 4 lacks.
https://www.notebookcheck.net/Raspberry-Pi-Transform-the-popular-single-board-computer-into-a-NAS-with-up-to-four-hard-drives.518179.0.html