import { NonceCache } from "@kya-os/contracts/handshake";
/**
 * DynamoDB client interface for SDK v3
 * Using 'unknown' for the client type to work with any AWS SDK version
 */
type DynamoDBClient = any;
/**
 * DynamoDB-based nonce cache implementation
 * Suitable for AWS Lambda deployments
 */
export declare class DynamoNonceCache implements NonceCache {
    private dynamodb;
    private tableName;
    private keyAttribute;
    private ttlAttribute;
    constructor(dynamodb: DynamoDBClient, tableName: string, keyAttribute?: string, ttlAttribute?: string);
    private getKey;
    has(nonce: string, agentDid?: string): Promise<boolean>;
    add(nonce: string, ttl: number, agentDid?: string): Promise<void>;
    cleanup(): Promise<void>;
}
export {};