Open-source alternatives to Undici

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

node-fetch is a lightweight HTTP client library that implements the browser-standard Fetch API for Node.js. It provides a promise-based interface for making asynchronous network requests to retrieve or send data from server-side environments. The project specializes in memory-efficient data handling by utilizing request and response streaming. This allows for the incremental processing of large network payloads through native system streams to prevent memory exhaustion. The library covers a broad range of networking capabilities, including the use of custom HTTP agents for DNS and SSL config

Superagent is a cross-platform JavaScript HTTP client and Ajax library used for exchanging data between clients and servers. It provides a consistent API for making network requests that works identically across both Node.js and web browser environments. The library features a request pipeline that allows for the addition of custom behaviors to outgoing network calls. This system supports the implementation of specialized functions such as request throttling, caching, and the automatic signing of outgoing data.

HTTPie is a command-line HTTP client designed for sending requests to web services and APIs. It functions as a terminal-based web client and JSON API interface, allowing users to interact with RESTful services and download remote files directly from the console. The tool simplifies the interaction with APIs through a custom syntax for argument parsing and automatic JSON payload serialization. It includes a request debugger to verify the structure of a request before transmission and uses ANSI-based formatting to display server responses with color and indentation for improved readability. Th

urllib3 is a Python HTTP client library used for sending network requests and receiving responses. It functions as an HTTP connection pool manager and a TLS certificate validator to ensure secure communication between endpoints. The library provides a system for maintaining reusable network connections to reduce the overhead of repeated handshakes. It also serves as an HTTP proxy client capable of routing requests through proxy servers to manage origin identity or bypass firewalls. The tool covers programmatic file uploads via multipart encoding and automated network resilience through the u

gost is a multi-protocol proxy tunnel and secure tunneling server designed to route network traffic through encrypted connections. It functions as a traffic obfuscation gateway and a transparent proxy server capable of intercepting TCP and UDP traffic at the IP level. The project also includes a virtual network interface manager for creating TUN and TAP devices to intercept operating system packets. The system distinguishes itself through a chain-based request routing model, allowing traffic to pass through an ordered sequence of proxy nodes. It provides extensive transport-layer encapsulatio

This project is a JavaScript fetch polyfill and HTTP client library. It implements the Fetch API in environments that lack native browser support for web requests, providing a promise-based network wrapper for executing asynchronous HTTP calls and managing responses. The library ensures a consistent interface across different JavaScript runtimes by mapping raw network data into standardized request and response objects. It utilizes the XMLHttpRequest object to perform network operations in environments where a native fetch implementation is unavailable. The tool covers HTTP request managemen

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

http-parser is a C-based library for extracting request and response metadata from raw HTTP data streams. It utilizes a state-machine approach to identify message segments and boundaries. The project implements zero-copy string parsing and pointer-based URL deconstruction to avoid memory allocations and data duplication. It supports incremental stream processing to handle fragmented data chunks and includes mechanisms for decoding chunked encoding and managing network protocol upgrades.

Got is a promise-based HTTP request library for Node.js that supports HTTP/2 and streaming. It provides a system for making network requests with a focus on asynchronous control flow and type-safe API client development. The library is distinguished by its middleware-based request lifecycle, which uses interceptors and plugins to modify request options and response data. It includes a configurable automatic retry mechanism with backoff strategies, a built-in HTTP response cache, and a cookie-jar system for maintaining persistent sessions. Broad capabilities cover data handling through duplex

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

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

The inspector is a diagnostic and validation tool for the Model Context Protocol. It provides an interactive interface and a transport proxy to discover, inspect, and execute the tools, prompts, and resources provided by an MCP server. The project serves as a debugger and compliance tester to verify that server implementations adhere to the protocol specification and JSON-RPC standards. It allows for real-time monitoring of message exchanges and logs between clients and servers across various transport layers, such as standard input/output and Server-Sent Events. The tool covers a broad rang

llrt is a low-latency JavaScript runtime based on the QuickJS engine, specifically designed for executing asynchronous functions in serverless environments. It provides a lightweight execution layer optimized for fast startup times and minimal memory usage when running ES2023 workloads. The project differentiates itself by bundling natively optimized cloud service SDKs directly into the runtime binary to eliminate external dependency loading. To further reduce cold start latency, it implements parallel connection warming for TLS and network handshakes during the startup phase. The runtime co

Requests is a high-level HTTP client library designed to simplify web communication and API integration. It provides an intuitive, human-readable interface for performing standard network operations, including request execution, connection pooling, and stateful session management. By encapsulating raw network data into structured objects, the library automates the complexities of headers, cookies, and payload transmission. The library distinguishes itself through a modular transport adapter layer that allows for custom protocol handling and extensible authentication hooks. It supports a wide

LibGDX is a Java-based framework designed for cross-platform game development, enabling the creation and deployment of 2D and 3D games across desktop, mobile, and web environments from a single codebase. It functions as a comprehensive library that abstracts hardware-accelerated graphics, audio, input, and file system access, providing a unified interface for developers to manage game logic and application lifecycles. The framework distinguishes itself through a high-performance architecture that prioritizes efficiency and native interoperability. It utilizes a batch-oriented graphics pipelin

This project is a comprehensive Python network request framework designed for both synchronous and asynchronous HTTP communication. It provides a high-performance client capable of executing non-blocking requests within event-driven applications, while also supporting standard blocking calls for simpler scripts. The library is built to operate natively across diverse asynchronous runtimes, automatically detecting and utilizing the underlying event loop for concurrency. What distinguishes this library is its modular architecture, which decouples request construction from network execution thro

Uvicorn is an ASGI web application host designed for asynchronous Python web development. It serves applications through a standardized asynchronous server gateway interface to handle non-blocking network traffic and high-concurrency requests. The server manages both HTTP and WebSocket traffic, including the handshaking process required to establish persistent, full-duplex communication channels for real-time data exchange. For development workflows, the project includes a hot-reload mechanism that monitors the filesystem for source code changes and automatically restarts the server process.

This project is an educational framework designed to teach the fundamentals of building core distributed systems and web services from scratch in Go. It provides a collection of modular implementations that demonstrate how to construct essential infrastructure components, including web servers, remote procedure call systems, distributed caches, and database abstraction layers. The framework distinguishes itself by focusing on the internal mechanics of these systems rather than providing a high-level abstraction for production use. It covers the implementation of complex architectural patterns

Webmin is a web-based administration interface for Unix systems. It provides a centralized console for managing the full range of server administration tasks — users and groups, software packages, storage, network configuration, system services, and security — all through a browser. Its modular architecture allows separate modules to handle databases (MySQL, MariaDB, PostgreSQL), web servers (Apache), DNS (BIND), email (Sendmail, Dovecot), file sharing (Samba, NFS), and more, with a unified access control system that restricts what each administrator can see and do. What sets Webmin apart is

Mimiclaw is a framework for integrating large language models with microcontroller hardware to create interactive AI agents. It provides an embedded AI agent runtime and a tool-calling engine that allows language model loops to execute on embedded devices. The system acts as a bridge between language model APIs and physical hardware peripherals, enabling the control of sensors and actuators through natural language. The project features a dedicated manager for over-the-air firmware updates, allowing system images to be installed via web browsers or wireless networks to remove local toolchain

Superagent is an isomorphic JavaScript HTTP client for sending network requests and processing responses across both Node.js and web browser environments. It provides a fluent request builder that uses a chainable interface to construct complex network requests with custom headers, query strings, and bodies. The library functions as a runtime-agnostic request adapter, allowing a single codebase to work consistently across different environments. It includes specialized capabilities such as an HTTP/2 client for forcing the HTTP/2 protocol and a Node.js agent for managing Unix socket connection

openapi-ts is a tool and orchestrator used to convert OpenAPI specifications into type-safe TypeScript SDKs and HTTP client implementations. It automatically generates typed interfaces and request functions from API definitions to ensure consistency between the server and the client. The project employs a transport-agnostic client interface, decoupling high-level API calls from the underlying network library. It uses a plugin-based generation pipeline and a custom plugin architecture to allow for the customization of output types and validation schemas. The system provides capabilities for n

HTTPie is a command-line HTTP client and REST API debugger used for sending requests to web services. It functions as a network tool for managing headers, authentication sessions, and file uploads, with a specific focus on the transmission and reception of JSON data. The tool utilizes a custom parsing layer to translate simplified command-line input into structured HTTP parameters. It provides ANSI-based terminal formatting to apply color and structural indentation to raw responses, improving human readability for web debugging. The project covers request construction and previewing, multipa

Hutool is a standard utility library for Java application development designed to simplify common programming tasks and reduce boilerplate code. It provides a comprehensive collection of reusable helper classes and static utilities to streamline development across the Java ecosystem. The project implements a wide array of specialized toolkits, including systems for cryptography and security, network communication via HTTP and JSON clients, and the processing of office documents and file system IO. It also features a concurrency and scheduling framework for managing asynchronous tasks and recu

Hutool is a comprehensive suite of Java extensions designed to serve as a standard library extension. Its primary purpose is to reduce development boilerplate for common programming tasks and data manipulation through a collection of utility classes. The project provides specialized toolkits for database management using active record patterns and connection pooling, as well as network communication via a simplified HTTP client and asynchronous socket management. It includes security and identity capabilities such as symmetric and asymmetric encryption, image captcha generation, and JWT token

This project is the .NET Base Class Library, providing the foundational types and APIs required for .NET applications. It serves as a cross-platform runtime library and a standardized managed API framework, acting as the primary set of namespaces for memory management, collections, and asynchronous programming. The library enables the development of enterprise backend infrastructure and the execution of managed code consistently across different operating systems and hardware architectures. It includes capabilities for cross-platform application deployment using self-contained binaries, frame