auto build = std::make_shared<Build>();

            auto build = std::make_shared<Build>(
                localStore->parseStorePath(row["drvPath"].as<string>()));

            build->drvPath = localStore->parseStorePath(row["drvPath"].as<string>());

            step = std::make_shared<Step>();
            step->drvPath = drvPath.clone();

            step = std::make_shared<Step>(drvPath.clone());

    Build(nix::StorePath && drvPath) : drvPath(std::move(drvPath))
    { }

    Step(nix::StorePath && drvPath) : drvPath(std::move(drvPath))
    { }