a flake breaking my hydra

flake.nix

{
  description = "a broken flake to report a bug";
  outputs = { self }: {
    hydraJobs.test.x86_64-linux = derivation {
      name = "test"; builder = "/bin/sh"; args = ["-c" "/bin/sh -c :> $out"];
      system = "x86_64-linux";
      __contentAddressed = true;
      outputHashAlgo = "sha256"; outputHashMode = "recursive";
    };
  };
}