Customizing nixpkgs¶

Some packages in nixpkgs require extra configuration before they can be used. Common cases:

• A package is marked as unfree (e.g. terraform, vault) and Nix refuses to build it.
• You need a patched or overridden version of a package.

To handle this, you can override the pkgs instance that nix-shell-parts uses.

Create a file like ./nix/nixpkgs-customization.nix:

{self, ...}: {
  perSystem = {system, ...}: {
    _module.args.pkgs = import self.inputs.nixpkgs {
      inherit system;
      config.allowUnfree = true;
    };
  };
}

Then import it in your flake.nix:

outputs = inputs @ {flake-parts, ...}:
  flake-parts.lib.mkFlake {inherit inputs;} {
    imports = [
      inputs.nix-shell-parts.flakeModules.default
      ./nix/nixpkgs-customization.nix
    ];

    perSystem = {...}: {
      shells.default.imports = [./nix/devshell.nix];
    };
  };

For more advanced use cases like overlays, see the flake-parts documentation.