On the install page, I read:
Install Nix via the recommended multi-user installation:
$ sh <(curl -L https://nixos.org/nix/install)
However, it doesn’t work with Fish:
fish: Invalid redirection target:
sh <(curl -L https://nixos.org/nix/install)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
I’m pretty sure there is a syntax that works with both.
You might get more support in a fish community, but you can try piping instead.
curl -L https://nixos.org/nix/install | sh
Or better, download the install script manually and review it before running.
My point was to improve the doc so that Fish users can copy/paste the examples without extra troubles (for both Fiash and Bash users).
You found the one outdated variant of the too many places with installation instructions. Opened a PR to fix the immediate problem, but eventually we should fix the underlying issue.