import { NextFunction, Request, Response } from 'express';
type PageData = {
    title?: string;
    description?: string;
    ogImage?: string;
    embed?: string;
};
type FallbackOptions = {
    root?: string | undefined;
    getPageData?: (req: Request) => PageData | Promise<PageData>;
    timeout?: number;
    maxLength?: number;
    cacheTtl?: number;
    injectBlockletJs?: boolean;
};
declare const fallback: (file: string, options?: FallbackOptions) => (req: Request, res: Response, next: NextFunction) => Promise<void>;
export { fallback };