/** backend time - at the time the response was generated - in seconds (aka 'epoch') -  */
export declare const getBackendTimeSeconds: (apiUrl: string, apiHeaders?: Record<string, string>) => Promise<number>;
/** determine the expected backend time right now in seconds (aka 'epoch') */
export declare const getBackendTimeNowSeconds: (apiUrl: string, apiHeaders?: Record<string, string>) => Promise<number>;