Comment by conartist6
5 hours ago
Pain is a signal. Even if the trick is not minding, it's still inadvisable to burn your hand on an open flame. The pain is there to help you not get hurt.
I do not think it is wise to brag that your solution to a problem is extremely painful but that you were impervious to all the pain. Others will still feel it. This code takes bandwidth to host and space on devices and for maintainers it permanently doubles the work associated with evolving the filesystem APIs. If someone else comes along with the same kind of thinking they might just double those doubled costs, and someone else might 8x them, all because nobody could feel the pain they were passing on to others
I don't see it to be such a pain.
> Bundle a full application into a Single Executable.
Embed a zip file into the executable, or something. Node sort of supports this since v25, see --build-sea. Bun and Deno support this for a longer time.
> Run tests without touching the disk.
This must be left to the host system to decide. Maybe I want them to touch the disk and leave traces useful for debugging. I'd go with tmpfile / tmpdir; whoever cares, knows to mount them as tmpfs, which sits in RAM. (Or a ramdisk under Windows.)
> Sandbox a tenant’s file access. In a multi-tenant platform, you need to confine each tenant to a directory without them escaping
This looks like a wrong tool, again. Run your Node app in a container (like you are already doing), mount every tenant's directory as a separate mount point into your container. (Similar with BSD jails.) This seems like the only problem that is not trivial to solve without a "VFS", but I'm not very certain that such a VFS would be as well-audited as Docker, or nsenter and unshare. The amount of work necessary for implementing that is too much for the niche benefit it would provide.
> Load code generated at runtime. See tmpfs for a trivial answer. For a less trivial answer, I don't see how Node's code loader is bound to a filesystem. If it can import via https, Just use ESM loader hooks and register() your loader, assuming you're running Node ≥ 20.6.