private static Map<String, String> assembleSystemProps() {
    Map<String, String> props = new HashMap<String, String>();
    Properties properties = System.getProperties();
    for (String key : properties.stringPropertyNames()) {
      props.put(key, properties.getProperty(key));
    }
    Map<String, String> env = System.getenv();
    for (Map.Entry<String, String> entry : env.entrySet()) {
      props.put("env." + entry.getKey(), entry.getValue());
    }
    return props;
  }