30 open-source projects similar to smol-rs/smol, ranked by shared indexed features. Tags may describe platforms or build tools rather than the same primary purpose. Check each project’s use case, license, and deployment requirements before treating it as a replacement.
Mio is a low-level I/O library for Rust that provides an event-driven framework for monitoring multiple network sockets and file descriptors. It acts as a portable wrapper for operating system native polling systems, including epoll, kqueue, and IOCP, allowing applications to trigger events when resources are ready for reading or writing without blocking the execution thread. The library provides a non-blocking socket interface for managing TCP, UDP, and Unix sockets. It distinguishes itself through a vectored I/O implementation, enabling scatter-gather reads and writes across multiple buffer
Asio is a C++ library for performing network and low-level I/O operations using a consistent asynchronous model that avoids blocking program execution. It provides a portable, cross-platform interface for network socket communication across different operating systems, and manages multiple asynchronous operations without requiring explicit thread management or locking. The library implements a proactor-based asynchronous model where operations post completion handlers to a queue for later execution, and wraps operating system I/O multiplexing mechanisms like epoll, kqueue, IOCP, and select in
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
This project is a technical study and analysis guide focused on the internal architecture of Node.js. It provides an in-depth examination of the runtime, focusing on how the engine manages memory handles, executes asynchronous operations, and implements core module logic. The guide specifically analyzes the integration of native C++ classes and functions into JavaScript and documents the behavior of the libuv event loop. It includes detailed references for optimizing performance by identifying V8 compiler bailouts and profiling execution to improve resource efficiency. The material covers a
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
Trio is an asynchronous I/O runtime and concurrency library for Python. It provides a system for executing non-blocking network and disk operations through a centralized event loop and task scheduler. The library is built on a structured concurrency model, which ensures that asynchronous tasks are bound to a specific lifetime and cannot outlive the scope that started them. It utilizes a nursery-based task manager to track task lifecycles in a parent-child tree, preventing orphaned concurrent operations by requiring child tasks to be joined before their parent scope exits. The framework cover
monoio is a high-performance asynchronous runtime and executor for Rust. It implements a thread-per-core concurrency model that pins tasks to specific CPU cores to eliminate synchronization overhead and data migration. The runtime leverages the io_uring interface to perform non-blocking system calls and reduce kernel-user mode memory copying. It utilizes a high-performance I/O driver and zero-copy TCP stream wrapping to manage data transfer via shared-memory buffers. The project provides capabilities for CPU core affinity management, low-latency system programming, and high-performance netwo
libuv is a cross-platform asynchronous I/O library that provides an abstraction layer for event-driven networking, filesystem operations, and system signals. It utilizes a non-blocking event loop to coordinate asynchronous tasks and I/O events across different operating systems. The project features a unified interface for managing TCP, UDP, and DNS resolution, alongside an inter-process communication layer for sharing sockets via named pipes and Unix domain sockets. To prevent blocking the main execution loop, it includes a multi-platform thread pool for offloading computationally expensive
cppcoro is a C++ coroutine library and concurrency toolkit providing primitives for asynchronous tasks, lazy generators, and non-blocking execution. It functions as an asynchronous I/O framework for managing network sockets and file operations through an event loop. The library features a work-stealing thread pool for distributing tasks across multiple cores and a set of async generators for producing lazy sequences of values both synchronously and asynchronously. It includes a concurrency toolkit with async mutexes, latches, and shared tasks to coordinate multi-threaded execution. Its capab
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
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
Swoole is a coroutine-based concurrency library and IO framework for PHP. It provides a system for building high-performance network servers and applications by bringing asynchronous, event-driven, and coroutine-based concurrency to the PHP runtime. The project distinguishes itself by implementing user-space coroutine scheduling and non-blocking IO interception, which transforms standard blocking network and file operations into asynchronous actions. It further enables high-speed data exchange across multiple PHP processes through shared memory management and specialized data structures. The
Kore is an event-driven web and WebSocket server framework designed for building high-performance web services and APIs in C or Python. It functions as a secure, concurrent application framework that utilizes non-blocking I/O and isolated worker processes to handle high-concurrency traffic. The project is distinguished by a security-first architecture that features OS-level process sandboxing, privilege separation, and the isolation of private encryption keys into dedicated processes. It enables zero-downtime deployments through dynamic module hot-reloading and provides automated TLS certific
async-std is a Rust asynchronous runtime and non-blocking I/O library. It serves as an asynchronous standard library, providing a set of alternatives to the core Rust library for managing concurrent tasks, networking, and file system access. The project implements a standard-library-mirrored API, offering asynchronous versions of existing synchronous types to maintain a familiar interface. This approach allows for asynchronous Rust development using an interface that reflects the ergonomics of the language's standard library. The runtime includes a task executor for scheduling and executing
libhv is a high-performance C/C++ network library and event-driven I/O framework used to build TCP, UDP, SSL, HTTP, WebSocket, and MQTT clients and servers. It provides a non-blocking event loop for managing network sockets, timers, and system signals across multiple threads. The project is distinguished by its integrated support for specialized network roles, including a full HTTP web server with RESTful routing and middleware, an MQTT messaging client for IoT communication, and the ability to implement SOCKS5 and HTTP proxies. It also features a reliable UDP implementation to ensure ordered
Boost is a collection of portable, high-performance source libraries that extend the C++ standard library. It provides a wide range of reusable components, data structures, and algorithms designed to add capabilities to the base language across different platforms. The project is distinguished by its extensive focus on compile-time template metaprogramming and generic programming. It implements advanced architectural patterns such as policy-based design, concept-based type validation, and the use of SFINAE for conditional template resolution to minimize runtime overhead. The library covers a
This project is a curated educational guide and instructional resource for the Node.js runtime environment. It serves as a comprehensive introduction to core concepts, including asynchronous programming tutorials, network application primers, and guides on the module system and stream API. The material focuses on the fundamental building blocks of server-side development, specifically how to create reusable code packages and manage project dependencies via a module manifest. It provides detailed instruction on building programs that communicate over HTTP and TCP protocols to exchange data acr
EventMachine is a reactor-pattern network framework for Ruby that provides an asynchronous I/O library for performing non-blocking network and file operations. It functions as a network server framework used to build scalable TCP and UDP servers and clients that process multiple simultaneous requests. The framework implements a concurrency model that dispatches network events to registered handlers using a single-threaded event loop. This approach allows for the management of high-concurrency network connections without the overhead of multi-threaded programming. The library covers the devel
This project is a detailed analysis and study of the Nginx source code, focusing on high-performance server architecture and function call flows. It serves as a technical examination of the internal C implementation used to build high-concurrency networking systems. The project deconstructs the internal mechanisms of the web server, including the multi-process master-worker model, event-driven asynchronous I/O, and non-blocking socket communication. It analyzes the phase-based request processing lifecycle, from URI matching and header parsing to final content generation. The study covers a b
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
Netpoll is an event-driven network framework and non-blocking I/O library designed to manage concurrent TCP and Unix domain socket connections. It utilizes a non-blocking event loop to monitor file descriptors and trigger callbacks for read and write events, serving as a high-performance socket manager and TCP network poller. The framework optimizes throughput across CPU cores by distributing incoming network connections across multiple pollers. It implements zero-copy networking primitives, using linked buffers and specialized memory management to read and write data while minimizing memory
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
Swift NIO is a low-level, event-driven network framework for the Swift language. It serves as an asynchronous network protocol stack and I/O library designed to build high-performance network servers and clients that handle thousands of simultaneous connections. The framework functions as a high-concurrency network engine that dispatches events across multiple CPU cores. It enables the implementation of custom network protocols by processing raw bytes through a sequence of reusable data transformation handlers. The system provides capabilities for non-blocking I/O multiplexing, asynchronous
Async-task is a low-level Rust concurrency library and asynchronous task executor designed for building custom asynchronous runtimes and managing background task execution pipelines. It provides concurrency primitives that handle atomic task state management, heap-allocated futures, output retrieval, and type-erased execution handles. The library coordinates task execution, cancellation, and polling states across multiple threads using lock-free atomic operations and reference counting. Developers can supply custom scheduling logic and metadata hooks that dictate when and how tasks are queue
Armeria is a Netty-based microservice framework used for building high-performance asynchronous services. It functions as a multi-protocol RPC server capable of exposing gRPC, Thrift, and REST services on a single unified port. The project is distinguished by its ability to run diverse communication protocols simultaneously and its integrated RPC debugging web console, which allows for the discovery and invocation of remote procedure calls via JSON. It also includes a gRPC to JSON transcoder to enable web client compatibility with Protobuf services. The framework provides a comprehensive sui
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
WinFSP is a framework for implementing custom file systems on Windows. It enables the creation of user-mode file systems that appear as standard disk drives or network shares to the operating system, allowing developers to implement file system logic in user space via a proxy architecture that avoids the need for custom kernel code. A primary differentiator is its FUSE compatibility layer, which maps POSIX-based file system calls to native Windows requests. This allows existing file systems written for the FUSE API to be ported to Windows and Cygwin environments. The project covers a wide ra
threads.js is a JavaScript worker thread library and asynchronous task orchestrator designed to offload CPU-intensive tasks to background threads. It functions as a cross-platform worker pool and a TypeScript worker runner that automatically transpiles and executes TypeScript files within separate threads. The project distinguishes itself by providing a unified worker API that allows for cross-platform execution across different JavaScript environments. It includes a specialized worker data serialization tool to pass complex class instances and binary data between threads, and supports inlini
ZIO is a functional effect system for the JVM that models asynchronous and concurrent programs as pure, composable values with typed error handling and dependency injection. Its core identity is built on fiber-based concurrency, where lightweight, non-blocking fibers execute millions of concurrent tasks with structured lifecycle management, and a dual-channel error model that separates expected business failures from unexpected system defects at compile time. The system provides effect-typed dependency injection through a layer-based dependency graph, pull-based reactive stream processing with
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