Events.ts is a Deno module that implements typings to the Node.js event emtter.
deno run https://deno.land/x/events_ts/example.ts
or
import EventEmitter from 'https://deno.land/x/events_ts/mod.ts';
const emitter = new EventEmitter<{ message: [message: string] }>();
emitter.on('message', console.log);
emitter.emit('message', 'Hello, World!');