/**
 * Based entirely on:
 * https://github.com/Polymer/tools/blob/e731b880a0d94a551f5781111f2f9c81cb64c642/packages/polyserve/src/compile-middleware.ts
 */
import { RequestHandler } from 'express';
import * as LRU from 'lru-cache';
export declare const babelCompileCache: LRU.Cache<string, string>;
export declare const getCompileCacheKey: (requestPath: string, body: string) => string;
export declare function babelCompile({ rootDir, modulesUrl }?: {
    rootDir?: string;
    modulesUrl?: string;
}): RequestHandler;