Open-source alternatives to Libvldmail

s2n is a C-based security library and TLS protocol implementation that serves as a secure network transport layer. It provides a modular cryptographic backend interface to encrypt data streams, manage handshakes, and handle mutual authentication between peers. The project focuses on post-quantum cryptography, integrating quantum-resistant key exchange and digital signatures to protect connections against future computing threats. It distinguishes itself through security hardening measures, such as memory-locked secret storage to prevent keys from being swapped to disk and timing-attack mitiga

A portable MQTT C client for embedded systems and PCs alike.

WAFer is a C language-based software platform for scalable server-side and networking applications. Think node.js for C programmers.

the LIBpcap interface to various kernel packet capture mechanism

Zyre - an open-source framework for proximity-based peer-to-peer applications

Wrapper library for the BSD sockets API with a nicer C99 interface

nanomsg is a distributed messaging middleware and scalable messaging library designed for moving data between machines and processes. It functions as a socket-based communication framework that routes data across different network transport layers. The library implements scalable messaging patterns, specifically request-reply and publish-subscribe, to handle high volumes of data across distributed systems. It provides tools for network performance benchmarking to quantify messaging throughput and latency. The framework supports distributed message routing and inter-process communication usin

🚀Gev is a lightweight, fast non-blocking TCP network library / websocket server based on Reactor mode. Support custom protocols to quickly and easily build high-performance servers.

Elegant Fast Fourier Transform in C. Making fft.c from fftpack user-friendly.

C List - universal list solution for C and C++, easy and fast, all data types supported

RabbitMQ C client

Parser combinators for binary formats, in C. Yes, in C. What? Don't look at me like that.

Epoxy is a library for handling OpenGL function pointer management for you

Alamofire is an HTTP networking library that provides a foundation for managing network requests and responses through a chainable, type-safe interface. It serves as an asynchronous request manager, coordinating concurrent network operations and data streams while maintaining application responsiveness. The library distinguishes itself through a protocol-oriented request adaptation system, which utilizes interceptors to modify or authenticate requests before dispatch. It employs a middleware-driven pipeline to process traffic, handling encoding, authentication, and error recovery in a modular

Linenoise is a lightweight C library for terminal line editing, command history management, and asynchronous input processing. It functions as a self-contained alternative for capturing user input from the command line without requiring external dependencies. The utility provides a non-blocking input processor that handles keyboard data via a feed mechanism, allowing applications to process user typing and external events simultaneously. It supports the implementation of custom shells and REPLs through features such as callback-based autocompletion, input hinting, and a circular history buffe

sds is a C dynamic string library that provides a memory management wrapper for heap-allocated strings. It implements binary-safe storage by tracking string lengths explicitly, allowing the library to handle null characters within data. The library distinguishes itself through a memory architecture that uses interchangeable function pointers for allocation and freeing, enabling the integration of custom memory managers. It utilizes header-stored length tracking to provide constant-time length retrieval and maintains null-terminated buffer padding to ensure compatibility with standard C string

Small strings compression library

Small & portable byte-aligned LZ77 compression

EasyLogger is a lightweight C/C++ logging library and asynchronous framework designed for embedded systems, IoT devices, and wearables. It functions as a resource-efficient logger and flash memory manager, providing tools for low-level debugging and system event recording with minimal ROM and RAM requirements. The project distinguishes itself through an asynchronous logging model that buffers messages to a separate thread, preventing logging operations from blocking real-time application execution. It includes a specialized flash memory manager that utilizes circular buffering to persist logs

An ultra-lightweight database that supports key-value and time series data | 一款支持 KV 数据和时序数据的超轻量级数据库

lightmapper.h is a C/C++ single-file library for lightmap baking by using your existing OpenGL renderer.