C# HTTP Client Libraries

Flurl is a .NET fluent URL builder and HTTP client wrapper designed for constructing complex web addresses and sending requests with a chainable interface. It functions as a URL manipulation library and an HTTP mocking framework to facilitate network interaction and testing. The project distinguishes itself through a fluent interface that allows for the incremental construction of paths, query parameters, and fragments. It provides a dedicated mocking system to intercept outgoing network traffic and return predefined responses, enabling isolated unit testing without a live server. Its broade

RestSharp is a .NET HTTP client library designed for interacting with RESTful web services. It provides a high-level request wrapper and a dedicated REST API client to manage endpoints, headers, and query parameters. The library includes a serialization mechanism that automatically converts objects to and from JSON or XML formats for API payloads. It also features a system for managing API credentials and security tokens to ensure authorized access to protected remote resources. The toolkit covers broad capabilities for external web service integration, including generic type-based deseriali

Refit is a type-safe REST client for .NET that transforms API definitions into live interfaces. It functions as an automatic API proxy generator, allowing developers to define endpoints as interfaces to eliminate manual HTTP request boilerplate. The library is designed for compatibility with ahead-of-time compilation and trimmed binaries, utilizing build-time source generation to ensure support for native AoT deployments. The project covers a broad range of API integration capabilities, including attribute-driven request composition, automatic JSON deserialization, and request header managem

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

Curl is a command-line tool and portable library for transferring data across a wide range of network protocols. It functions as a unified engine that abstracts diverse communication standards, allowing users and developers to move files and information between servers using a consistent interface. The project provides both a versatile command-line client for terminal-based automation and a stable programmatic interface for integrating complex network operations into applications. The system is distinguished by its protocol-agnostic core and its ability to manage both synchronous and asynchro

Pingora is a Rust-based framework for building high-performance network services, including HTTP reverse proxies, layer seven load balancers, and TLS termination proxies. It serves as an asynchronous network library designed to intercept and route HTTP, gRPC, and WebSocket traffic between clients and upstream backend servers. The project enables zero-downtime service updates by handing over listening sockets between processes during binary or configuration upgrades. It utilizes a programmable multi-phase pipeline to modify request and response bodies and headers, and it provides a pluggable T

Retrofit is a type-safe HTTP client that simplifies network communication by allowing developers to define API endpoints as interface methods. By using annotation-driven request mapping, it automatically translates these interface definitions into structured HTTP requests, ensuring consistent data structures and reducing manual configuration when interacting with remote web services. The project distinguishes itself through a highly modular architecture that separates network transport from data handling. It utilizes dynamic proxy generation to process method calls at runtime and offers a plu

This project is a terminal-based HTTP client designed for interacting with web services, debugging APIs, and automating network requests. It provides a specialized command-line interface that simplifies the construction of complex HTTP exchanges, allowing users to test and inspect web services directly from the shell. The tool distinguishes itself through a declarative syntax engine that translates shorthand command-line tokens into fully formed HTTP requests, including headers, parameters, and body payloads. It features a modular, plugin-based architecture that enables users to extend core f

This project provides a comprehensive implementation of the WebSocket protocol, enabling persistent, bidirectional communication between clients and servers. It handles the low-level complexities of the protocol, including the initial HTTP upgrade handshake and the encapsulation of data into discrete binary frames. By managing these connections, it allows applications to exchange data instantly without the overhead associated with repeated standard request cycles. The library distinguishes itself through its focus on high-frequency message exchange and concurrent connection management. It uti