class InternalStepRunner implements StepRunner {

    static NodeResources testerResourcesFor(ZoneId zone, DeploymentInstanceSpec spec) {
        return spec.steps().stream()
                   .filter(step -> step.concerns(zone.environment()))
                   .findFirst()
                   .flatMap(step -> step.zones().get(0).testerFlavor())
                   .map(NodeResources::fromLegacyName)
                   .orElse(zone.region().value().contains("aws-") ?
                           DEFAULT_TESTER_RESOURCES_AWS : DEFAULT_TESTER_RESOURCES);
    }

    public  InternalStepRunner(Controller controller);

}