Determinate Nix is Determinate Systems’ enterprise‑grade, validated downstream distribution of NixOS/Nix that retains full compatibility with upstream Nix while adding performance‑boosting features such as parallel evaluation and lazy trees.

Setup

Add the input determinate and the module determinate.nixosModules.default to your system flake.nix configuration

{
  inputs.determinate.url = "https://flakehub.com/f/DeterminateSystems/determinate/*";
  inputs.nixpkgs.url = "nixpkgs/nixos-25.11";
 
  outputs = { determinate, nixpkgs, ... }: {
    nixosConfigurations.my-workstation = nixpkgs.lib.nixosSystem {
      system = "x86_64-linux";
      modules = [
        # Load the Determinate module
        determinate.nixosModules.default
      ];
    };
  };
}

After that add the two extra options to your nixos-rebuild command and apply changes

sudo nixos-rebuild \
  --option extra-substituters https://install.determinate.systems \
  --option extra-trusted-public-keys cache.flakehub.com-3:hJuILl5sVK4iKm86JzgdXW12Y2Hwd5G07qKtHTOcDCM= \
  --flake ... \
  switch