whatisgithub

Popular C repositories on GitHub, each answered in plain English for non-coders: what it is, its tech stack, and how to run it.

• alibaba/tengineTengine is a web server created by Alibaba's Taobao that extends Nginx with live config reloads, HTTP/3, Lua s
• jonas/tigTig is a terminal-based Git browser that shows commits, diffs, blame views, and lets you stage changes interac
• softethervpn/softethervpnSoftEther VPN is an open-source VPN server that speaks nearly every major VPN protocol at once — OpenVPN, Wire
• doctorwkt/acwjA 64-part tutorial series that walks you through writing a real C compiler from scratch in C, starting from re
• freerdp/freerdpFree open-source implementation of Microsoft's Remote Desktop Protocol that lets you connect to and control Wi
• qemu/qemuQEMU is an open-source machine emulator that lets you run software or entire operating systems built for one p
• openwall/johnJohn the Ripper is an offline password-auditing tool that recovers original passwords from stored hashes, supp
• libretro/retroarchRetroArch is a single app that runs dozens of game emulators via a plugin system called cores, covering consol
• duixcom/duix-avatarDuix.Avatar is a local desktop tool that creates realistic AI-generated videos of a digital copy of you — prov
• nmap/nmapNmap is the most widely used open-source tool for discovering devices on a network, finding open ports, and id
• raspberrypi/linuxThe Linux kernel source code with Raspberry Pi-specific patches, for developers who need to compile a custom k
• microsoft/mimallocmimalloc is a drop-in replacement memory allocator from Microsoft Research that makes programs faster and more
• cesanta/mongooseA tiny two-file C networking library for embedded devices and microcontrollers that provides HTTP, WebSocket,
• octalmage/robotjsA Node.js library for controlling the mouse, keyboard, and screen from JavaScript on Mac, Windows, and Linux.
• davegamble/cjsonA tiny JSON parser for C programs that fits in a single source file and header. Copy two files into your proje
• citusdata/citusCitus is a PostgreSQL extension that spreads your database across multiple machines so it can handle far more
• darktable-org/darktableAn open-source photography application for organizing your photo library and editing RAW camera files non-dest
• google/sanitizersAn archived Google repository that documented a family of bug-finding tools for C and C++ programs — the tools
• twitter/twemproxyA lightweight C proxy server created at Twitter that reduces connection overhead to Redis and Memcached cluste
• openzfs/zfsOpenZFS is a file system and storage manager for Linux and FreeBSD that combines multiple disks into pools, pr
• rt-thread/rt-threadRT-Thread is an open-source real-time operating system for microcontrollers and IoT devices, available in a 1.
• redcanaryco/atomic-red-teamAtomic Red Team is a library of nearly 1,800 small command-line tests that simulate real attacker behaviors so
• libevent/libeventA mature C library that lets a single program handle thousands of simultaneous network connections efficiently
• lz4/lz4LZ4 is an extremely fast lossless compression library in C that compresses at over 500 MB/s and decompresses a
• vanhauser-thc/thc-hydraHydra is an authorized login-testing tool that automates checking username and password combinations across mo
• openresty/lua-nginx-moduleAn Nginx plugin that lets you write request-handling logic in Lua scripts running inside Nginx itself, enablin
• felixkratz/sketchybarA fully customizable replacement for the macOS menu bar that you build and style yourself using shell scripts,
• rui314/chibiccA teaching C compiler that handles most of C11 — built commit by commit as the reference code for a book on co
• tsl0922/ttydA tool that shares a terminal session through a web browser — run it on any server and anyone with the URL can
• klipper3d/klipperOpen-source 3D printer firmware that runs the heavy math on a Raspberry Pi instead of the printer's own chip,
• tencent/wcdbA production-grade mobile database library from Tencent, used inside WeChat, that wraps SQLite with ORM, encry
• h2o/h2oA high-performance web server written in C that supports HTTP/1, HTTP/2, and experimental HTTP/3, built for sp
• libvips/libvipsA fast C image processing library with 300+ operations — resize, crop, convert, filter — that uses far less me
• apple/darwin-xnuThe source code for XNU, the hybrid kernel at the heart of macOS and iOS, combining the Mach microkernel, Free
• screetsec/thefatratA Linux penetration testing tool that automates generating remote-access payloads for Windows, Android, Mac, a
• immediate-mode-ui/nuklearNuklear is a single-file C library for building immediate-mode GUIs with no dependencies, designed to plug int
• krallin/tiniTini is a tiny init process for Docker containers that cleans up zombie processes and ensures Docker stop sign
• cyan4973/xxhashUltra-fast hashing library in C that turns data into fingerprints at speeds faster than RAM — built for non-se
• fogleman/craftA Minecraft-style voxel sandbox game written from scratch in a few thousand lines of C, with procedural terrai
• leandromoreira/ffmpeg-libav-tutorialHands-on C tutorial that teaches you to use FFmpeg as a programming library rather than a command-line tool, c
• betaflight/betaflightOpen-source drone flight controller firmware that manages motors, sensors, and pilot inputs, with a web-based
• andlabs/libuiA C library for building desktop apps that look and behave natively on Windows, macOS, and Linux by using each
• eclipse-mosquitto/mosquittoEclipse Mosquitto is an open source MQTT message broker that receives messages from connected devices and rout
• jemalloc/jemallocjemalloc is a high-performance memory allocator for C programs that reduces memory waste and speeds up apps ru
• pymumu/smartdnsA local DNS server that queries multiple upstream servers simultaneously and returns the fastest IP address fo
• immortalwrt/immortalwrtImmortalWrt is an OpenWrt fork that replaces consumer router firmware with a full Linux-based system, adding m
• dicedb/dicedbDiceDB is a Redis-compatible database that automatically moves data to disk when memory fills up, letting you
• rswier/c4c4 is a minimalist C compiler and interpreter written in just four C functions — a programming curiosity that
• syllo/nvtopNVTOP is a terminal dashboard for monitoring GPU usage, memory, temperature, and power draw in real time, simi
• rofl0r/proxychains-ngA Linux command-line tool that transparently forces any program to route its network traffic through SOCKS4, S
• i3/i3i3 is a minimal, keyboard-driven tiling window manager for Linux that automatically arranges all open applicat
• libgit2/libgit2A C library that lets your application read and write Git repositories directly, without calling the git comma
• cstack/db_tutorialA guided tutorial for building a simplified SQLite-like database engine from scratch in C, teaching how databa
• microsoft/wsl2-linux-kernelThe Linux kernel source code that Microsoft ships with Windows Subsystem for Linux 2 (WSL2) — the actual kerne
• imbushuo/mac-precision-touchpadA Windows driver that makes Apple trackpads work with full gesture support on Windows 10, covering MacBooks fr
• yugabyte/yugabyte-dbA distributed database that looks and behaves like PostgreSQL but runs across multiple servers or cloud region
• phpredis/phpredisPhpRedis is a compiled C extension for PHP that lets your PHP code talk to Redis at native speed, enabling fas
• huangzworks/redis-3.0-annotatedA line-by-line Chinese-annotated copy of the Redis 3.0 source code, created as a companion to the book 'Redis
• tporadowski/redisAn unofficial Windows port of Redis that lets developers run the popular in-memory database natively on 64-bit
• tencent/xluaxLua lets developers write Lua scripts inside C# Unity games and hot-patch shipped bugs at runtime without req
• ahrm/sioyekSioyek is a PDF viewer built for reading research papers and textbooks, with smart citation jumping, portals t
• mit-pdos/xv6-publicxv6 is a tiny Unix-like operating system written at MIT in C — small enough to read completely — used worldwid
• henrypp/memreductMem Reduct is a small Windows utility that monitors RAM and frees memory by clearing internal Windows caches,
• wireshark/wiresharkWireshark captures and lets you inspect every packet traveling across a network connection — widely used for t
• appimage/appimagekitAppImageKit is the toolkit for packaging Linux desktop apps as single portable files that run on any distro —
• peng-zhihui/electronbotA complete open-source hardware and software kit for building a small desk robot inspired by WALL-E's EVE — in
• jgamblin/mirai-source-codeThe leaked source code of the Mirai botnet, republished with documentation for defensive security research — s
• happyfish100/fastdfsA distributed file storage system that spreads files across a cluster of servers for redundancy and high throu
• telekom-security/tpotceAll-in-one honeypot platform from Telekom Security that runs 20+ honeypots simultaneously in Docker containers
• microsoft/react-native-code-pushAn archived React Native plugin that let developers push JavaScript updates directly to users' phones without
• torch/torch7Torch7 is an early machine learning framework written in C with a Lua scripting layer — now unmaintained and p
• mattn/go-sqlite3A Go library that connects Go's standard database interface to SQLite, letting your Go programs store and quer
• meetecho/janus-gatewayAn open-source WebRTC media server written in C that you self-host to build real-time audio and video apps — v
• freebsd/freebsd-srcThe complete source code for the FreeBSD operating system — kernel, shell, libraries, networking stack, and st
• adaway/adawayAdAway is a free, open-source Android ad blocker that stops ads and tracking at the network level using either
• unicorn-engine/unicornA CPU emulation framework that lets software pretend to be an ARM, x86, MIPS, or other processor, so security
• nonstriater/learn-algorithmsA personal collection of study notes on classic algorithms and data structures implemented in C, covering sort
• antirez/kiloA minimal terminal text editor written in fewer than 1,000 lines of C with no external library dependencies, d
• xfennec/progressA Linux and macOS command-line tool that shows the percentage, speed, and estimated time remaining for running
• wind4/vlmcsdA KMS server emulator written in C that activates Windows and Office on local networks, running on Linux, macO
• pygame/pygamePygame is a Python library for building 2D games and multimedia apps, handling graphics, sound, and input on t
• irungentoo/toxcoreToxcore is the C library powering the Tox protocol — enabling encrypted peer-to-peer messaging, file transfers
• capstone-engine/capstoneC disassembly library that reads raw bytes from a binary and returns human-readable CPU instructions and regis
• secwiki/windows-kernel-exploitsA community-maintained reference list of proof-of-concept exploit code for Windows kernel privilege escalation
• shellphish/how2heapA collection of C programs demonstrating real heap memory exploitation techniques used in security research an
• n64decomp/sm64A reverse-engineered version of Super Mario 64 in readable C code that recompiles into a byte-perfect copy of
• winfsp/winfspA Windows platform for building custom file systems — create a virtual drive that appears in Explorer and work
• flightlessmango/mangohudMangoHud shows a live performance overlay on your screen while you play games on Linux, displaying metrics lik
• squeaky-pl/japrontoA Python web framework built for maximum speed using a C-based HTTP server core, capable of handling over a mi
• 0xfa11/multiplayernetworkingresourcesA curated list of articles, videos, and tools explaining how multiplayer games keep players in sync over the i
• esnet/iperfiperf3 is a command-line tool that measures actual data transfer speed between two machines on a network, repo
• skeeto/endlesshEndlessh is a tiny C program that wastes the time of automated SSH scanners by pretending to be an SSH server
• henrypp/simplewallsimplewall is a lightweight Windows app that blocks all internet access by default and lets you choose exactly
• antirez/ds4A dedicated local inference engine for running the DeepSeek V4 Flash language model on high-end personal hardw
• ctcaer/hekateA custom bootloader for the Nintendo Switch that replaces the normal startup process, letting you choose what
• peng-zhihui/l-ink_cardA DIY smart card project that combines NFC with an e-ink display and a dial to switch between multiple stored
• jart/blinkA tiny virtual machine that runs x86-64 Linux programs on Mac, Windows, ARM, and RISC-V without needing Linux,
• phoboslab/qoiQOI is a fast, lossless image format implemented as a single C/C++ header file—compression similar to PNG but
• merbanan/rtl_433Turns a cheap USB radio dongle into a decoder for hundreds of wireless home devices — weather stations, temper
• openmathlib/openblasOpenBLAS is a fast math library that speeds up matrix and linear algebra operations, used behind the scenes by

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