Open-source alternatives to Sockjs Client

Socket.IO Client is a real-time WebSocket client library that establishes persistent bidirectional connections to a server, with automatic fallback to HTTP long-polling when WebSocket connections are unavailable. It provides an event-based bidirectional messaging framework where clients and servers exchange named events with serializable data, supporting acknowledgements and timeouts for reliable communication. The client distinguishes itself through automatic reconnection with exponential backoff, maintaining connection reliability by monitoring health and reconnecting with increasing delays

This project is a high-performance implementation of the QUIC transport protocol, providing a library for establishing multiplexed, low-latency network connections over UDP. It serves as a foundational networking stack for building modern web servers and clients, with native support for HTTP/3 and WebTransport standards. The library distinguishes itself through advanced connection management, including the ability to maintain stable sessions across changing network paths or IP addresses using connection identifiers. It optimizes data throughput by employing packet batching to reduce kernel ov

SignalR is a .NET real-time web framework designed to push content from a server to connected browser and non-browser clients. It provides a server-to-client push framework and a remote procedure call system that enables bidirectional communication over persistent connections. The library utilizes WebSockets to establish full-duplex connections and includes a transport-layer abstraction to manage different network protocols. It employs client-side connection negotiation to determine the best available communication protocol during the initial handshake. The system manages persistent connecti

Socket.io is a real-time communication engine that enables bidirectional, event-based data exchange between clients and servers. It provides a robust transport-agnostic protocol layer that automatically manages connection lifecycles, including heartbeat signals, automatic reconnection, and seamless fallback between WebSockets and HTTP long-polling. By maintaining persistent links, it ensures reliable messaging across diverse network environments. The project distinguishes itself through a scalable, distributed architecture that supports multi-node synchronization and room-based message routin

KCP is a low-latency transport protocol and reliability layer designed to provide TCP-like guaranteed delivery and ordering over UDP. It implements an automatic repeat request protocol to minimize network jitter and delays, prioritizing timeliness over bandwidth efficiency. The project distinguishes itself through a pluggable congestion controller and flow control logic, allowing the transport layer to be tuned for specific network environments. It includes a NAT keep-alive system that uses periodic heartbeat packets to maintain active communication paths and prevent address translation timeo

Faye is a real-time messaging middleware and WebSocket publish-subscribe server. It functions as a communication layer that routes messages between clients and manages channel subscriptions to enable data synchronization across the web. The project provides a cross-domain communication gateway, allowing web clients on different domains to communicate with a central server. It is built as a clustered messaging backend that can share state across multiple instances using external storage to handle high volumes of persistent network connections. Its capability surface includes pub-sub logic for

embedded-notes is a collection of technical study guides and development notes focused on embedded Linux, Linux kernel internals, and C programming. It serves as a reference for embedded systems development and a preparation resource for technical interviews in the field. The project provides detailed documentation on writing device drivers, managing virtual memory, and understanding kernel internals. It also includes guides on IoT network protocols, such as MQTT and TCP/IP, and outlines the architectural details of chip architectures and hardware peripherals. The material covers a broad sur

This project is a memory-safe implementation of the QUIC transport protocol and HTTP/3, designed for high-throughput and efficient network communication. It provides a comprehensive toolkit for building secure, low-latency network applications by managing the full lifecycle of transport connections, including protocol negotiation, stream data exchange, and connection state management. The library distinguishes itself through a focus on performance and protocol integrity. It utilizes a formal state machine to enforce strict adherence to transport rules and employs zero-copy buffer management t

This project is a Node.js WebSocket library that provides a high-performance client and server implementation for the WebSocket protocol. It functions as a transport layer for real-time bidirectional communication, supporting both UTF-8 strings and binary data transport through the use of TCP socket wrappers. The library enables the creation of WebSocket servers that manage full-duplex connections and broadcast messages to multiple clients, as well as WebSocket clients that establish persistent links to remote servers. It handles the protocol upgrade process via TCP-based handshake negotiatio

websocket-sharp is a C# library implementation of the WebSocket protocol used for building bidirectional client and server applications. It enables real-time data exchange between endpoints via persistent connections. The library provides specialized networking capabilities, including SSL encrypted networking for secure transport and certificate validation. It also features HTTP proxy tunneling to route traffic through intermediary servers using basic or digest authentication. The project covers a broad range of capabilities, including the implementation of both WebSocket clients and servers

This project is a library for establishing bidirectional, real-time communication channels between clients and servers using the WebSocket protocol. It provides a foundational toolkit for managing persistent network connections and processing data frames in accordance with the RFC 6455 standard. The library distinguishes itself through its focus on low-level control and network efficiency. It utilizes an asynchronous, event-driven architecture to manage multiple concurrent connections without requiring dedicated threads for each session. Developers can fine-tune data transmission through manu

Phoenix is a server-side web framework built for the Elixir programming language and the Erlang virtual machine. It provides a structured environment for developing applications using the model-view-controller pattern, enabling developers to manage data, render user interfaces, and handle incoming requests within a scalable, process-based architecture. The framework distinguishes itself as a platform for real-time web communication, utilizing persistent bidirectional connections to broadcast live updates to clients. It incorporates a dedicated abstraction layer for relational database integra

This is a header-only C++ library that provides implementations for HTTP clients, HTTP servers, and a WebSocket framework. It allows for the creation of network services and the consumption of remote APIs without requiring a separate compilation step or external binary linking. The project features backend-agnostic TLS integration for secure HTTPS and WSS communication and employs a thread-pool model to process concurrent requests. It distinguishes itself with a full-duplex WebSocket state-machine and a middleware-based request pipeline that supports regular-expression path routing. The libr

Simpl is an HTML, CSS, and JavaScript example library that provides a collection of minimal functional demonstrations of core web technologies and native browser APIs. It serves as a reference implementation and pattern gallery for frontend development, offering practical examples of how to implement common web features. The project showcases a wide range of browser capabilities, including real-time web communication via WebSockets and WebRTC, responsive web design techniques for adaptive layouts, and the implementation of offline workflows using service workers. It also provides demonstratio

Crow is a minimalist C++ micro web framework designed for building fast web servers and REST APIs. It provides a lightweight toolkit for web development in C++, offering core routing and request handling capabilities. The framework includes a built-in JSON parser for converting strings into structured data and an HTML template engine for generating dynamic web pages on the server. It also functions as a WebSocket server library to enable bidirectional, real-time communication between servers and web clients. Additional capabilities include a middleware-based request pipeline for executing sh

BrowserQuest is a WebSocket multiplayer game engine and real-time state synchronization tool. It functions as a web-based game server designed to manage concurrent connections and broadcast updates to maintain a consistent shared world state between a central server and distributed web clients. The project enables real-time multiplayer gaming and browser-based game development by implementing low-latency data exchange. It focuses on game state synchronization to ensure that multiple players interacting within the same environment see the same actions and world states simultaneously. The syst

FastHTML is a full-stack Python web framework designed for building interactive web applications using pure Python. It functions as an HTMX integration framework and a Python HTML domain-specific language, allowing developers to generate HTML structures using native objects and functions instead of external templating files. The framework is distinguished by its native support for real-time bidirectional communication via WebSockets and Server-Sent Events, enabling server-side updates to be pushed to the browser without full page reloads. It further integrates identity management through OAut

WebSocket-Node is a server-side implementation of the WebSocket protocol for Node.js environments. It serves as a framework for establishing persistent, bidirectional communication channels and low-latency data exchange between clients and servers. The project provides a secure socket implementation using transport layer security and includes an integrated client for establishing outbound encrypted connections. It utilizes a formal protocol-state machine and an event-driven connection framework to manage high-concurrency network streams. The framework covers server-side infrastructure includ

Message Bus is a messaging library for Ruby and Rack applications designed to facilitate real-time data broadcasting and inter-process communication. It provides a framework for pushing live updates to connected clients and synchronizing state across multiple application instances, ensuring consistent data delivery in scaled environments. The library distinguishes itself through a flexible architecture that supports multiple storage backends, including Redis, PostgreSQL, and in-memory options. It functions as a persistent connection framework that serves as an alternative to traditional web s

This project is a JavaScript full-stack tutorial providing a step-by-step guide to building a complete web application from scratch. It focuses on the manual implementation of a custom JavaScript toolchain, encompassing the development of a server-side rendering workflow and a client-side state manager. The project distinguishes itself by implementing core development utilities without high-level frameworks, including custom solutions for bundling, transpilation, linting, and hot module replacement. It also features a real-time communication system based on WebSockets for bidirectional messag

Atmosphere is a Java-based framework for building and coordinating AI agents. It provides a real-time transport layer for streaming data via WebSockets, SSE, gRPC, and WebTransport, alongside a multi-agent orchestration framework for managing agent fleets through sequential, parallel, and graph-based execution workflows. The project features a durable workflow engine that persists agent state as snapshots, allowing long-running tasks to survive system restarts and incorporate human-in-the-loop approvals. It also implements Model Context Protocol servers to expose tools, resources, and prompt

Starscream is a Swift WebSocket client library that provides a concrete implementation of the WebSocket protocol for iOS and macOS applications. It functions as an event-driven wrapper for establishing and managing bidirectional connections to send and receive text and binary frames over TCP. The library includes a secure WebSocket client capable of encrypting traffic and validating server identities. It manages the full connection lifecycle, from the initial handshake and header exchange to session termination with custom close codes. The project covers a broad range of networking capabilit

Elysia is a high-performance TypeScript web framework designed for building type-safe backend services. It provides a modular, plugin-based architecture that allows developers to compose server logic, middleware, and validation schemas into scalable application instances. By leveraging native web standards, the framework ensures portability across diverse JavaScript runtimes, including Node.js, Deno, and various edge computing environments. The framework distinguishes itself through its focus on end-to-end type safety, automatically synchronizing request and response definitions between the s

ASP.NET Core is a unified, cross-platform framework designed for building scalable web applications and services. It provides a comprehensive environment for constructing server-side rendered applications, real-time communication services, and interactive web components using C# and .NET. The framework distinguishes itself through a modular architecture that centers on a built-in dependency injection container, which manages service lifecycles and component modularity to improve testability. It utilizes a middleware pipeline to process requests and employs policy-based authorization to secure

This is a minimal WebSocket library for Go designed for bidirectional real-time communication. It serves as a network protocol implementation for managing handshakes, frame masking, and control signals to enable the exchange of text and binary messages over persistent connections. The library distinguishes itself by providing a connectivity layer that wraps browser WebSocket APIs for applications compiled to WebAssembly. It also functions as data compression middleware, utilizing deflate compression to reduce bandwidth usage for transmitted messages. The project covers a broad range of netwo

Liveblocks is a realtime collaboration infrastructure platform that synchronizes application state, documents, and user presence across multiple participants using conflict-free replicated data types. It provides a managed backend for collaborative text editors, threaded commenting and annotation systems, in-app notifications, and AI copilot deployment, all built on a WebSocket transport layer with server-side room management APIs. The platform distinguishes itself through a headless component primitive system that exposes unstyled React hooks and composable building blocks, allowing develope

tg-ws-proxy is a local proxy server and network tool designed to route Telegram traffic through WebSocket connections. It functions as a bridge that tunnels MTProto protocol traffic to bypass network restrictions and circumvent firewalls that block direct connections to messaging services. The project includes a system tray proxy manager that provides a desktop interface for controlling the server state. This manager allows for updating connection secrets, viewing server logs, and restarting services through a native OS desktop tray icon. The system supports establishing proxy connections vi