import { EventEmitter } from "events";
export type Callback = (eventName: string, data: any) => void;
export declare class EventBus extends EventEmitter {
    private static instance;
    private constructor();
    static getInstance(): EventBus;
    subscribe(eventName: string, callback: Callback): void;
    unsubscribe(eventName: string, callback: Callback): void;
    publish(eventName: string, data: any): void;
}