TLS/SSL and crypto library

World's fastest and most advanced password recovery utility

Redis is an in-memory database that persists on disk. The data model is key-value, but many different kind of values are supported: Strings, Lists, Sets, Sorted Sets, Hashes

A single-header ANSI C gui library

H2O - the optimized HTTP/1, HTTP/2, HTTP/3 server

John the Ripper jumbo - advanced offline password cracker, which supports hundreds of hash and cipher types, and runs on many operating systems, CPUs, GPUs, and even some FPGAs

Screaming-fast Python 3.5+ HTTP toolkit integrated with pipelining HTTP server based on uvloop and picohttpparser.

Pony is an open-source, actor-model, capabilities-secure, high performance programming language

A query and indexing engine for Redis, providing secondary indexing, full-text search, vector similarity search and aggregations.

Lightweight Ruby

Arm Mbed OS is a platform operating system designed for the internet of things

Simple Unit Testing for C

OSv, a new operating system for the cloud.

Keyboard firmwares for Atmel AVR and Cortex-M

Mintty as a terminal for Bash on Ubuntu on Windows / WSL

FuzixOS: Because Small Is Beautiful

A readable lisp in less than 1k lines of C

ngx_mruby - A Fast and Memory-Efficient Web Server Extension Mechanism Using Scripting Language mruby for nginx

Vulkan API bindings for Go programming language

A demo that should be run with ESP8266 Non-OS SDK

PicoRuby is the smallest Ruby implementation for one-chip microcontrollers

32-bit RISC-V CPU in ~800 lines of C89

Teensy Core Libraries for Arduino

Dr Strangehack, or: how to write a self-hosting C compiler in 10 hours

Cortex Microcontroller Software Interface Standard (V4 no longer maintained)

mruby/c is another implementation of mruby.

profiler/logger/oobgc for rgengc in ruby 2.1

Memory-hard scheme Argon2

privilege separation engine for OpenSSL / LibreSSL