GC Warning: Failed to expand heap by 4194304 KiB GC Warning: Failed to expand heap by 4194304 KiB GC Warning: Failed to expand heap by 4194304 KiB GC Warning: Failed to expand heap by 4194304 KiB GC Warning: Failed to expand heap by 4194304 KiB error: … while evaluating attribute 'drv' at /nix/store/kwli1syc3yhl69wcl9690i8gwbawsj8x-filnix-experiment-0.13.3/lib/experiment/planner.nix:14:3: 13| { 14| drv = p.drvPath; | ^ 15| name = p.name; … while evaluating the attribute 'drvPath' at /nix/store/hlfn8kjj2lavprbpvrza71w7k08jfk1y-source/lib/customisation.nix:418:7: 417| // { 418| drvPath = | ^ 419| assert condition; (stack trace truncated; use '--show-trace' to show the full, detailed trace) error: Package ‘iozone-3.507’ in /nix/store/hlfn8kjj2lavprbpvrza71w7k08jfk1y-source/pkgs/by-name/io/iozone/package.nix:66 has an unfree license (‘unfreeRedistributable’), refusing to evaluate. a) To temporarily allow unfree packages, you can use an environment variable for a single invocation of the nix tools. $ export NIXPKGS_ALLOW_UNFREE=1 Note: When using `nix shell`, `nix build`, `nix develop`, etc with a flake, then pass `--impure` in order to allow use of environment variables. b) For `nixos-rebuild` you can set { nixpkgs.config.allowUnfree = true; } in configuration.nix to override this. Alternatively you can configure a predicate to allow specific packages: { nixpkgs.config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [ "iozone" ]; } c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add { allowUnfree = true; } to ~/.config/nixpkgs/config.nix. GC Warning: Failed to expand heap by 4194304 KiB