alt Hacker NewsYarn, pnpm, webpack all have solutions for this. Great to see this becoming a standard. I have a project that is severely handicapped due to FS. Running 13k tests takes 40 minutes where a virtual file system that Node would just work with it would cut the run time to 3 minutes. I experimented with some hacks and decided to stay with slow but native FS solution.
What I really want is a way of swapping FS with VFS in a Node.js program harness. Something like
node --use-vfs --vfs-cache=BIG_JSON_FILE
The way to do this today is to do it outside of node. Using an overlay fs with the overlay being a ramfs. You can even chroot into it if you can't scope the paths you need to be just downstream from some directory. Or, just use docker.