$ nix eval '.#è'
4
$ nix eval '.#测试'
3
$ cat flake.nix  
{
  outputs = { self }: {
    "测试" = 3;
    "è" = 4;
  };
}

oh yeah this is so funny

$ nix registry add test path:$(pwd)
$ nix eval 'test#%C3%A8'           
4
$ nix eval 'test#%E6%B5%8B%E8%AF%95'
3

unrelatedly
John Ericson i just noticed this meeting minutes https://discourse.nixos.org/t/2025-05-28-nix-team-meeting-minutes-229/65205 especially about #13042, and ... it doesn't really make sense to me.

Appears to be a problem with running 32-bit x86 on x86_64-linux. This should work, but is possibly host-dependent and seccomp may interfere.

No, it's trying to run 64-bit programs in a 32-bit derivation, which fails as expected. It should not work and the build is wrong.

The basic issue is that the code was written assuming cross

Incomplete sentence? If "assuming cross builds don't run tests" was meant then yes that's correct

(Temporarily dropping this here because I'm not sure where I should be putting it.)