Reminisce means to talk, write, or think about past experiences with pleasure and nostalgia.

Unix, the operating system, is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix.

Remnix is a combination of these two words, and has nothing to do with NixOS, the Linux distribution.

It is a play on words, and is meant to be a fun and memorable name for the project.

remember unix (commands) is not the official mnemonic, but it is a fun way to remember the name.