Serena is an experimental operating system for 32bit Amiga computers, developed by Dietmar Planitzer. The kernel is object-oriented and designed to be cross-platform and future-proof. The features are: Dispatch queues, virtual processors, memory management, SerenaFS file system, ROM and RAM-disks, floppy disk driver, Zorro II & III, keyboard, mouse, joystick, …
From: Retro Roundup