{
  "slug": "socket-io",
  "name": "Socket.IO",
  "url": "https://socket.io",
  "cat": "rt",
  "group": "back",
  "tagline": "Open-source WebSocket library",
  "price": "Free and MIT licensed, with no hosted service and no vendor bill — you pay only for the server you run it on. The Redis and cluster adapters used for multi-node scaling are also free",
  "tier": "free",
  "pick": false,
  "what": "Node.js library wrapping WebSockets with automatic reconnection, HTTP long-polling fallback, rooms, namespaces and message acknowledgements; version 4.x is current. Scaling past a single process requires an adapter such as Redis to broadcast between nodes. Client libraries exist for browsers, React Native, Python, Java and Swift.",
  "why": "Zero vendor bill and total control over the protocol. If you already run a Node server, adding live comments or a presence counter is one dependency and about twenty lines, not a new SaaS contract with a per-message meter.",
  "warn": "You own the operations: sticky sessions behind the load balancer, a Redis adapter once you exceed one node, and reconnect storms after every deploy. Most serverless hosts — Vercel and Netlify functions among them — cannot hold the long-lived connections it needs.",
  "install": "npm i socket.io socket.io-client",
  "category": {
    "key": "rt",
    "name": "Realtime, comments & collab",
    "desc": "Live updates, comment systems, video, community.",
    "group": "back",
    "groupName": "Give it a backend"
  },
  "freshness": null,
  "health": {
    "ok": true,
    "status_code": 200,
    "final_url": "https://socket.io/",
    "checked_at": "2026-08-18T18:09:22.039+00:00"
  },
  "corrected_at": null,
  "upstream_changed_at": null
}