[frutiger]

nix has always been installable onto any *nix OS without requiring you to “fork an entire OS”.

You can put the nix store in any writable location and modify $PATH to point to the symlinks directory.

[rollcat]

Not if your / filesystem lacks the /nix directory to use as a mountpoint, and happens to be a read-only image. Something that needs a workaround on macOS.

[frutiger]

It has been a while since I last used it, but I was under the impression that the store location was customisable and thus could be anywhere?

[figomore]

Nix store can be anywhere. But if it’s not /nix Nix will not use the cache (already compiled packages) and compile every package needed.