import type { CorsOptions } from 'cors';
import type { RateLimitRequestHandler } from 'express-rate-limit';
import rateLimit from 'express-rate-limit';
import type { HelmetOptions } from 'helmet';
/**
 * Get CORS configuration based on environment
 */
export declare function getCorsOptions(): CorsOptions;
/**
 * Get Helmet configuration for enhanced security headers
 */
export declare function getHelmetOptions(): HelmetOptions;
/**
 * Create rate limiter with default configuration
 */
export declare function createRateLimiter(options?: Partial<Parameters<typeof rateLimit>[0]>): RateLimitRequestHandler;
/**
 * Create stricter rate limiter for authentication endpoints
 */
export declare function createAuthRateLimiter(): RateLimitRequestHandler;
/**
 * Create rate limiter for API endpoints
 */
export declare function createApiRateLimiter(): RateLimitRequestHandler;
/**
 * Additional security headers not covered by Helmet
 */
export declare function additionalSecurityHeaders(): (req: any, res: any, next: any) => void;