Simple, secure^[1] & standards compliant^[2] web server for the most demanding^[3] of applications. Read more...

µWebSockets.js is a C++ implementation of the Http/WebSocket protocols for Node.js, easy to use from JavaScript. Think of it as a faster Express.js/Socket.IO alternative; it comes with both router and pub/sub support. Browse the documentation and see the main repo. There are tons of examples but here's the gist of it all:

/* Non-SSL is simply App() */
require('uWebSockets.js').SSLApp({

  /* There are more SSL options, cut for brevity */
  key_file_name: 'misc/key.pem',
  cert_file_name: 'misc/cert.pem',
  
}).ws('/*', {

  /* There are many common helper features */
  idleTimeout: 30,
  maxBackpressure: 1024,
  maxPayloadLength: 512,
  compression: DEDICATED_COMPRESSOR_3KB,

  /* For brevity we skip the other events (upgrade, open, ping, pong, close) */
  message: (ws, message, isBinary) => {
    /* You can do app.publish('sensors/home/temperature', '22C') kind of pub/sub as well */
    
    /* Here we echo the message back, using compression if available */
    let ok = ws.send(message, isBinary, true);
  }
  
}).get('/*', (res, req) => {

  /* It does Http as well */
  res.writeStatus('200 OK').writeHeader('IsExample', 'Yes').end('Hello there!');
  
}).listen(9001, (listenSocket) => {

  if (listenSocket) {
    console.log('Listening to port 9001');
  }
  
});

Being written in native code directly targeting the Linux kernel makes it way faster than any JavaScript implementation.

Install with npm install uNetworking/uWebSockets.js#v18.4.0 or any such release. No compiler needed.

• Runs on Linux (x64, ARM64), macOS (x64) and Windows (x64). Node.js 10, 11, 12, 13 & 14.
• Installs from this GitHub repo, not the NPM registry. Production apps should rely on their own local copy.

uNetworking AB is a Swedish consulting & contracting company dealing with anything related to µWebSockets; development, support and customer success.

Don't hesitate sending a mail if you're building something large, in need of advice or having other business inquiries in mind. We'll figure out what's best for both parties and make sure you're not stepping into one of the many common pitfalls.

Special thanks to BitMEX, Bitfinex, Google, Coinbase, Bitwyre and deepstreamHub for allowing the project itself to thrive on GitHub since 2016 - this project would not be possible without these beautiful companies.

• µWebSockets.js is the Node.js binding to µWebSockets. Read more over at µWebSockets.