b) For `nixos-rebuild` you can set
         { nixpkgs.config.allowUnsupportedSystem = true; }
       in configuration.nix to override this.

       c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
         { allowUnsupportedSystem = true; }
       to ~/.config/nixpkgs/config.nix.
/nix/store/ycn1r0wfmlx1ak67gd9ihqivw78anyh1-vm-test-run-audit.drv
/nix/store/rg5ci80p7y2zfcwzp3zkpy7dsmvqxv4v-audit-x86_64-unknown-linux-musl-4.1.1-unstable-2025-08-01.drv!bin