Real-time & WebSockets

Socket.IO

socketio/socket.io

Popular

Bidirectional real-time events over WebSocket with fallbacks, rooms and auto-reconnect.

ws

websockets/ws

Popular

Fast, thoroughly tested WebSocket client and server for Node.js.

uWebSockets.js

uNetworking/uWebSockets.js

C++-backed WebSocket and HTTP server for Node.js tuned for very high connection counts.

SignalR

learn.microsoft.com

Popular

ASP.NET Core library for real-time hubs over WebSockets with automatic transport fallbacks.

PartyKit

partykit/partykit

Framework for stateful real-time servers on Cloudflare Durable Objects, with the partysocket client.

Centrifugo

centrifugal/centrifugo

Language-agnostic real-time messaging server (WebSocket, SSE, HTTP streaming) that scales via Redis or NATS.

Pusher Channels

pusher/pusher-js

Hosted pub/sub WebSocket service with simple client SDKs for live updates and notifications.

Laravel Reverb

laravel/reverb

First-party, Pusher-compatible WebSocket server for Laravel apps.

Ably

ably/ably-pubsub-js

Hosted real-time messaging platform with guaranteed ordering, presence and history.

Soketi

soketi/soketi

Legacy

Self-hosted, Pusher-compatible WebSocket server on uWebSockets.js; development has largely stalled.

SocketCluster

SocketCluster/socketcluster

Highly scalable realtime pub/sub and RPC framework

sockjs-client

sockjs/sockjs-client

WebSocket emulation - Javascript client