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Simple, secure1 & standards compliant2 web server for the most demanding3 of applications. Read more...

🔐 Optimized security

Being meticulously optimized for speed and memory footprint, ”WebSockets is fast enough to do encrypted TLS 1.3 messaging quicker than most alternative servers can do even unencrypted, cleartext messaging3.

Furthermore, we partake in Google's OSS-Fuzz with a ~95% daily fuzzing coverage4 with no sanitizer issues. LGTM scores us flawless A+ from having zero CodeQL alerts and we compile with pedantic warning levels.

▶ Rapid scripting

”WebSockets is written entirely in C & C++ but has a seamless integration for Node.js backends. This allows for rapid scripting of powerful apps, using widespread competence. See ”WebSockets.js.

Besides this Node.js integration, you can also use Bun where ”WebSockets is the built-in web server.

⚔ Battle proven

We've been fully standards compliant with a perfect Autobahn|Testsuite score since 20162. ”WebSockets powers many of the biggest crypto exchanges in the world, handling trade volumes of multiple billions of USD every day. If you trade crypto, chances are you do so via ”WebSockets.

🔋 Batteries included

Designed around a convenient URL router with wildcard & parameter support - paired with efficient pub/sub features for WebSockets. ”WebSockets should be the obvious, complete starting point for any real-time web project with high demands.

Start building your Http & WebSocket apps in no time; read the user manual and see examples. You can browse our TypeDoc for a quick overview.


    /* These are the most common options, fullchain and key. See uSockets for more options. */
    .cert_file_name = "cert.pem",
    .key_file_name = "key.pem"

}).get("/hello", [](auto *res, auto *req) {

    /* You can efficiently stream huge files too */
    res->writeHeader("Content-Type", "text/html; charset=utf-8")->end("Hello HTTP!");

}).ws<UserData>("/*", {

    /* Just a few of the available handlers */
    .open = [](auto *ws) {
    .message = [](auto *ws, std::string_view message, uWS::OpCode opCode) {
        ws->send(message, opCode);

}).listen(9001, [](auto *listenSocket) {

    if (listenSocket) {
        std::cout << "Listening on port " << 9001 << std::endl;
    } else {
        std::cout << "Failed to load certs or to bind to port" << std::endl;


đŸ’Œ Commercially supported

uNetworking AB is a Swedish consulting & contracting company dealing with anything related to ”WebSockets; 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 falling into common pitfalls.

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

🔧 Customizable architecture

”WebSockets builds on ”Sockets, a foundation library implementing eventing, networking and cryptography in three different layers. Every layer has multiple implementations and you control the compiled composition with flags. There are currently five event-loop integrations; libuv, ASIO, GCD and raw epoll/kqueue.

In a nutshell:

See ”Sockets for an up-to-date list of flags and a more detailed explanation.

đŸ€ Permissively licensed

Intellectual property, all rights reserved.

Where such explicit notice is given, source code is licensed Apache License 2.0 which is a permissive OSI-approved license with very few limitations. Modified "forks" should be of nothing but licensed source code, and be made available under another product name. If you're uncertain about any of this, please ask before assuming.