emittery
Simple and modern async event emitter
eventemitter3
EventEmitter3 focuses on performance while maintaining a Node.js AND browser compatible interface.
mqtt
A library for the MQTT protocol
eventemitter2
A feature-rich Node.js event emitter implementation with namespaces, wildcards, TTL, async listeners and browser/worker support.
nats
Node.js client for NATS, a lightweight, high-performance cloud native messaging system