Open-source alternatives to Cpp Httplib

Javalin is a lightweight web framework for Java and Kotlin designed for building REST APIs and web applications. It functions as an embedded Jetty web server, allowing applications to run as standalone processes without the need for an external servlet container. The project provides specialized frameworks for diverse communication patterns, including a REST API framework with automatic OpenAPI schema generation, a GraphQL API framework with query and mutation resolvers, and a WebSocket server for bidirectional real-time communication. It also includes a dedicated framework for pushing real-t

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

Hyper is a low-level networking library designed for building high-performance HTTP clients and servers. It provides a foundational toolkit for creating network services that leverage asynchronous execution and memory-safe data handling, supporting both HTTP/1 and HTTP/2 protocols. The library distinguishes itself through a protocol-agnostic architecture that separates transport logic from HTTP semantics. It utilizes a service-trait abstraction to decouple network logic from the underlying transport, enabling developers to inject custom middleware for request interception and response transfo

OkHttp is an HTTP client for the JVM and Android that enables network communication via synchronous and asynchronous requests. It provides a core identity as a comprehensive networking toolkit featuring a WebSocket client for bidirectional data synchronization, a TLS security toolkit for encrypted communication, and a programmable HTTP mock server for simulating backend responses. The project distinguishes itself through a specialized security and performance architecture. It implements mutual TLS, certificate pinning, and DNS over HTTPS to secure data in transit, while utilizing connection p

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

Fasthttp is a high-performance networking framework for Go, designed to maximize throughput and minimize memory overhead in demanding web applications. It functions as a specialized HTTP server and client library that prioritizes efficient resource management, allowing developers to build scalable services capable of handling massive concurrent traffic with minimal garbage collection pressure. The library distinguishes itself through a focus on zero-allocation processing and low-level optimization. It achieves this by recycling temporary request and response objects through managed pools and

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 is a header-only C++ library and asynchronous network framework used to implement WebSocket clients and servers. It provides a full implementation of the WebSocket protocol, including handshakes, subprotocol negotiation, and frame parsing. The framework is distinguished by a policy-based transport layer and template-driven protocol negotiation, allowing the underlying network implementation to be swapped between raw buffers, streams, or custom policies. It supports per-message deflate compression to reduce data transmission volume and integrates Transport Layer Security for encrypted bid

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

This is a non-blocking network client for Java applications that provides asynchronous HTTP request capabilities and bidirectional WebSocket connectivity. It leverages a Netty-based architecture to handle high volumes of network input and output. The library utilizes native transport abstractions such as Epoll, KQueue, and io_uring to reduce system latency. It supports HTTP/2 multiplexing to run multiple concurrent request-response streams over a single connection and provides automatic response body decompression for various formats. Core capabilities cover the management of complex network

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 project is a comprehensive sample library and implementation guide for ASP.NET Core. It provides a collection of practical examples and projects that demonstrate how to build web applications, RESTful APIs, and high-performance services. The repository focuses on a variety of architectural patterns, including the development of Minimal APIs, contract-first gRPC services, and real-time communication using WebSockets and Server-Sent Events. It includes detailed implementations for user identity and security, such as token-based authentication and CSRF protection. The codebase covers a bro

Cowboy is a high-performance HTTP server for Erlang and OTP. It is designed to handle web traffic with low memory usage and can be used as a standalone server or as an embedded networking library integrated directly into an existing application. The project implements modern transport protocols, including HTTP/3, QUIC, and WebTransport, to enable faster connections and bidirectional data streaming. It also functions as a real-time communication server supporting Server-Sent Events for pushing asynchronous updates to clients. Broad capabilities include path and content-type based request rout

Starlette is an asynchronous web framework and toolkit for building high-performance web services based on the ASGI specification. It serves as a lightweight foundation for creating web applications with a focus on asynchronous request and response handling. The framework provides specialized toolkits for managing persistent bidirectional WebSocket communication and an asynchronous HTTP server toolkit for routing and middleware. It distinguishes itself by offering a non-blocking background task queue that executes functions after a response has been sent to the client. The project covers a b

Echo is a high-performance, lightweight web framework for Go designed for building scalable RESTful APIs and web services. It provides a centralized environment for mapping network requests to handler functions, utilizing a fast radix-tree routing engine to ensure efficient request dispatching. The framework is built around a modular, middleware-centric pipeline that allows developers to execute reusable logic for cross-cutting concerns like authentication, logging, and security across the entire application. What distinguishes Echo is its focus on developer productivity through structured da

FastMCP is a Python framework designed for building servers that expose functions, resources, and prompts to AI models using the Model Context Protocol. It simplifies the development process by automatically deriving tool metadata, input schemas, and documentation directly from Python function signatures and type hints. The framework provides a unified container for managing these components, allowing developers to build modular applications that integrate seamlessly with AI assistants. The project distinguishes itself through its support for interactive, server-defined user interface compone

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

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

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-

Polka is a minimalist Node.js web framework and HTTP routing engine. It provides a small-footprint server implementation designed for low overhead, mapping URL paths and HTTP methods to specific handler functions. The project utilizes a middleware-based architecture, processing requests through a sequence of functions to handle tasks such as logging, authorization, and data modification. It allows for the organization of these functions into global and path-filtered groups to control execution order. The framework covers core web capabilities including route parameter extraction, request URL

Martini is a web framework for the Go programming language that provides a toolkit for building web applications. It functions as a routing engine and an HTTP middleware pipeline to map network requests to specific handler functions. The framework is distinguished by its dependency injection system, which automatically resolves and provides requested service types as arguments to handler functions. This allows for the decoupling of business logic from infrastructure by matching requested types against a registry of available services. The project covers a broad range of web capabilities, inc

cpr is a C++ networking library that provides a high-level HTTP request client. It functions as a wrapper around libcurl to simplify the process of sending and receiving data from web servers, specifically managing GET and POST calls and multipart form uploads. The library provides both synchronous and asynchronous execution models, allowing network requests to run on background threads to prevent application freezing. It integrates with the C++ Standard Library to map low-level pointers to standard strings and containers, utilizing RAII for automatic resource management. The project covers

Ring is a web application library for Clojure that standardizes HTTP traffic into immutable data structures. By defining application logic as pure functions that accept request maps and return response maps, it decouples web services from specific server implementations and transport protocols. The framework distinguishes itself through a functional approach to middleware composition, allowing developers to wrap handlers in reusable layers to manage cross-cutting concerns like authentication, logging, and data transformation. It supports both synchronous and asynchronous execution patterns, e

Oak is a cross-runtime HTTP middleware framework and web server designed to operate across Deno, Node.js, Bun, and Cloudflare Workers. It provides a unified system for building APIs and web servers using a sequential chain of middleware functions and a hierarchical routing engine that maps URL paths to handlers via a nested tree structure. The framework includes a runtime-agnostic serverless adapter that translates diverse cloud provider events into a standard request and response interface. It also features a dedicated WebSocket server implementation for bidirectional real-time communication

Guzzle is a PHP HTTP client used for sending synchronous and asynchronous requests to web services. It serves as a concurrent HTTP request manager, an HTTP stream handler, and a middleware-based HTTP pipeline. The project is a PSR-7 compliant client, utilizing standardized PHP interfaces for requests, responses, and streams. The library differentiates itself through a customizable functional handler stack that allows for the interception and modification of the request and response lifecycle. It features an adapter-based transport system that enables swapping between network implementations,