Open-source alternatives to Libhv

libwebsockets is an event-driven networking framework written in C. It provides a suite of tools for implementing HTTP servers and clients, WebSocket bidirectional communication, MQTT client messaging, and TLS-enabled socket encryption. The project distinguishes itself through a non-blocking event-loop architecture capable of scaling to high connection volumes by distributing network sessions across multiple service threads. It uses a protocol-based callback system and a pluggable event loop integration that allows the networking core to synchronize with external system event libraries. The

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

Java-WebSocket is a collection of classes for implementing WebSocket clients and servers using pure Java. It provides a framework for hosting servers that manage connections via event-driven subclasses and tools for establishing client connections to remote servers. The library includes a secure communication tool for encrypting traffic using the WSS protocol and a compression library that uses per-message deflate extensions to reduce transmitted data size. It supports the configuration of cipher suites to limit encryption protocols and ensure compatible communication. The project enables bi

Kitura is a server-side web framework for building HTTP services and web applications using the Swift programming language. It functions as an HTTP server that handles incoming requests, routes traffic, and serves responses. The framework serves as a Codable REST API framework, enabling the encoding and decoding of native Swift data types for web service communication. It also provides a FastCGI web interface to connect Swift applications to external web servers for improved scalability. The system includes capabilities for secure web communication through SSL/TLS network encryption, server-

NanoHTTPD is a lightweight, embeddable HTTP server for Java applications. It allows developers to integrate web server capabilities directly into a Java project to handle incoming requests without requiring a standalone installation. The project provides specialized implementations for an HTTPS web server, a WebSocket server for bidirectional real-time communication, and a static file web server. These capabilities enable secure network traffic through SSL certificates and the delivery of local files with automatic MIME type detection. The server includes systems for request routing and hand

TCP-IP-NetworkNote is a comprehensive technical reference and guide for implementing network communication using TCP and UDP sockets in C and C++. It provides a detailed manual for using the POSIX socket API and covers the implementation of network protocols, synchronous and asynchronous I/O patterns, and concurrent programming models. The project is distinguished by its focus on cross-platform networking, offering a detailed comparison of socket implementation details and adaptation utilities between Linux and Windows Winsock environments. It specifically addresses the differences in header

CppGuide is a curated collection of educational resources and practical guides focused on C++ server development, Linux kernel internals, concurrent programming, network protocols, and security exploitation. It provides structured learning paths for backend developers, covering everything from interview preparation to building high-performance network servers and understanding operating system fundamentals. The guide distinguishes itself by offering in-depth, hands-on tutorials that walk through real-world implementations, including building a Redis-like server from scratch, designing custom

Drogon is a high-performance C++ HTTP web framework and asynchronous web server designed for building web applications and REST APIs. It utilizes an event-driven, non-blocking architecture to handle concurrent HTTP and WebSocket connections, and it implements a model-view-controller structure to separate business logic from presentation. The framework includes an integrated C++ object-relational mapping system and database client for performing asynchronous operations with relational databases and Redis key-value stores. It supports real-time, full-duplex communication via WebSockets and prov

Muduo is a C++11 event-driven network library and framework designed for building high-concurrency Linux servers. It provides a toolkit for implementing scalable network services and socket communication using non-blocking I/O and asynchronous event processing. The framework implements a multi-threaded TCP server architecture that distributes connection handling across multiple CPU threads to maximize server throughput. This is achieved through a one-loop-per-thread model and a reactor pattern implementation, which dispatch network events from a central demultiplexer to registered handler fun

uWebSockets is a high-performance networking engine providing an HTTP web server and a WebSocket server framework. It implements a multi-threaded event loop architecture to deploy isolated application instances across multiple CPU cores and includes an SSL/TLS network layer for secure, encrypted communication. The project features a dedicated WebSocket pub/sub engine for distributing messages to specific groups of connected clients. It optimizes network throughput through syscall corking to reduce kernel overhead and employs payload compression to minimize data transfer sizes. The system cov

ReactPHP is an asynchronous runtime and event-driven I/O framework for PHP. It provides an environment for executing concurrent tasks through a central event loop implementation and reactor pattern, allowing applications to handle multiple operations without pausing the main execution thread. The project includes a specialized asynchronous socket library for TCP, UDP, and TLS communication, alongside a non-blocking HTTP server and client for streaming web requests and responses. Its capability surface covers asynchronous control flow via promises and fibers, non-blocking network connectivity

Robyn is a high-performance asynchronous web framework and server for Python that utilizes a Rust-powered runtime to execute code. It functions as an asynchronous Python web server designed to handle many concurrent requests efficiently through a multithreaded execution model. The project includes specialized capabilities for AI agent request routing, managing communication between agents and external tools. It also serves as a WebSocket communication server, maintaining persistent bidirectional channels for real-time data exchange. The framework covers a broad range of web infrastructure, i

Drogon is a high-performance, cross-platform C++ framework designed for building asynchronous web services and server-side applications. It functions as a multi-threaded, event-driven server engine that manages concurrent network traffic and WebSocket connections with minimal latency. By leveraging non-blocking input/output and native code compilation, the framework provides a foundation for scalable applications that operate efficiently across diverse hardware architectures. The framework distinguishes itself through its compile-time template rendering, which transforms dynamic HTML views in

aiohttp is an asynchronous networking framework for Python that provides both an HTTP client and an HTTP server. It utilizes the asyncio library to handle network requests and server-side routing through a non-blocking event loop. The framework includes a dedicated toolkit for establishing persistent bidirectional communication channels, enabling the implementation of both WebSocket servers and clients for real-time data exchange. It covers a broad range of asynchronous network programming capabilities, including the development of web servers with customizable routing and the ability to sen

Mongoose is an embedded networking library providing TCP/IP stacks, web server hosting, and IoT device connectivity. It enables microcontrollers and desktop systems to implement network protocols including HTTP, WebSocket, and MQTT. The project provides a bare-metal TCP/IP stack for environments without a native operating system and includes built-in TLS and ECC encryption to secure network traffic. It features a binary-embedded file system to serve web content directly from the executable and supports over-the-air firmware updates for managing device fleets. Additional capabilities cover as

Node.js is an open-source, cross-platform JavaScript runtime environment built on the V8 engine, designed for executing JavaScript code outside a web browser. It operates as a server-side JavaScript platform with an event-driven, non-blocking I/O architecture that enables building scalable network applications and web servers. The runtime integrates the CommonJS module system for synchronous module loading and the npm ecosystem for sharing and reusing packages. The platform provides comprehensive capabilities for web server development, including creating HTTP and HTTPS servers, managing HTTP

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

Gevent is a Python coroutine concurrency library and asynchronous task manager designed for high-concurrency I/O tasks. It provides a cooperative networking framework for building asynchronous TCP, UDP, and HTTP servers, as well as a WSGI web server implementation for hosting web applications. The project is distinguished by its standard library monkey-patching tool, which replaces blocking synchronous functions with cooperative versions to enable asynchronous behavior in third-party code. This allows for a cooperative multitasking workflow where the system yields execution during I/O waits t

Handy is a C++11 network server framework and event-driven networking engine designed for building high-performance concurrent TCP and UDP servers. It functions as an asynchronous I/O library and an HTTP server implementation that separates asynchronous network I/O from synchronous business logic to simplify server development. The framework distinguishes itself by utilizing platform-specific event notifications to manage millions of simultaneous network connections and providing an SSL/TLS network wrapper for encrypted asynchronous data transmission. It implements a half-sync/half-async proc

Kitura is a server-side web framework for building web applications and APIs using the Swift programming language. It provides a native HTTP server for hosting network traffic and implementing REST APIs. The framework features a pluggable middleware architecture that allows for the insertion of custom logic into the request-response pipeline. It utilizes a Codable data processor to automate the serialization and deserialization of HTTP requests and responses using Swift data models. The system includes a trie-based route matching mechanism for mapping URL paths to handlers and supports the F

Vibora is an asynchronous Python web framework and built-in HTTP server designed for building high-performance web applications. It utilizes an asynchronous event loop and coroutines to process network requests and serve responses without requiring external server wrappers. The project features a high-performance asynchronous schema validator for request integrity, a non-blocking template engine with support for hot-reloading, and a WebSocket communication server for bidirectional real-time data exchange. The framework covers a broad range of capabilities, including modular route management

This library is an MQTT client implementation designed for resource-constrained embedded systems, specifically targeting ESP8266 microcontrollers. It provides a framework for establishing persistent network connections to exchange data with remote messaging brokers, enabling reliable communication for IoT devices. The library distinguishes itself through its ability to maintain simultaneous connections to multiple independent messaging brokers, facilitating complex data routing across distributed environments. It utilizes a state-machine approach to manage connection lifecycles, including aut

Perfect is a server-side Swift framework designed for building high-performance web applications, REST APIs, and backend services. It provides an asynchronous HTTP server that handles web traffic through an event loop, alongside a web template engine for generating dynamic HTML pages. The project includes a WebSocket communication library for implementing bidirectional, real-time data exchange between clients and servers. It also provides a database connector to establish connections and exchange data between Swift applications and external database stores. The framework's capabilities cover

Vector is a high-performance observability data pipeline designed to collect, transform, and route logs, metrics, and traces across distributed infrastructure. It functions as a modular engine that decouples data ingestion from processing and transmission, utilizing a component-based architecture to connect diverse sources to multiple destinations. The project distinguishes itself through a focus on reliability and flow control. It implements backpressure-aware data movement to prevent data loss during traffic spikes and utilizes disk-backed event buffering to ensure durability during network

Libevent is a cross-platform library that provides a mechanism for executing callback functions when specific events occur on file descriptors, signals, or timers. It functions as a network event loop framework, enabling the development of applications that manage concurrent network connections and non-blocking input and output operations within a single execution context. The library distinguishes itself by providing a portable abstraction layer that automatically selects the most efficient system-level event notification mechanism available on the host operating system. It includes thread-s

Proxygen is a collection of C++ libraries for building high-performance HTTP servers and clients. It provides a protocol parser that converts raw network bytes into high-level transaction objects and includes a network stack for processing web traffic over the QUIC transport protocol. The project implements a layered protocol abstraction and a QUIC-based transport integration to support multiple versions of the HTTP standard, including HTTP/3. It utilizes state-machine based parsing and an event-driven I/O loop to manage concurrent network connections. The library covers asynchronous buffer

AndroidAsync is a non-blocking networking library for Android that provides asynchronous sockets, HTTP clients, and servers based on Java NIO. It serves as a toolkit for managing raw TCP socket connections and bidirectional data streams using an asynchronous input and output architecture. The library includes a dedicated WebSocket framework for establishing persistent full-duplex communication channels between Android clients and servers. It also enables the hosting of a lightweight asynchronous HTTP server directly on an Android device to handle incoming network traffic. Its broader capabil