Windows NT has been designed as a layered and extensible operating system, especially with regard to the storage and I/O subsystem. We can easily add new devices by writing a driver of the appropriate type (such as a SCSI miniport driver or a Storport minidriver).
It is fairly easy to add functionality to Windows NT by adding a storage device driver that is a filter driver. Microsoft itself has written such a driver as part of its Hierarchical Storage Management application.
Writing Windows NT drivers requires a fair amount of specialized knowledge and access to the appropriate development kits.