stb single-file public domain libraries for C/C++

AddressSanitizer, ThreadSanitizer, MemorySanitizer

Simple and portable (but not inflexible) GUI library in C that uses the native GUI technologies of each platform it supports.

Objective-C for Windows

C macros for hash tables and more

A library of common data structures and algorithms written in C.

Plan 9 from User Space

Cycle-Accurate Nintendo 64 Emulator

A minimal new SSH client for Mac OS 7/8/9

Cartridge for the Commodore 64 that packs a punch

runtime function overriding for Mac OS X

Adapting USB devices to work on old computers

A C++ port of Wave Function Collapse Tiling

MIP – macOS Injection Platform

USB Keyboard/Mouse/Gamepads on Retro Computers!

OpenMucom88 project

Decode the analog waveform extracted from old computer mag tapes

various tools that convert game data into MIDI files

Replace aging vintage computer power supply with modern ATX PSU

FUSE driver for HFS+ filesystems

Constraint-based layout manager for GTK+

A YM2413 emulator written in C.

Small tool for exploring visual styles (aka themes) on Windows XP and later, as provided by UXTHEME.DLL.

A bunch of tools for handling the MDX music format (music for the Sharp x68000)

FM synthesiser based on emulated Yamaha YM chips (OPL, OPM and OPN series)

[development paused; issues and PRs still welcome] Portable UTF-8 and UTF-16 routines in a single C source file.

Displays the progress file on 16-bit Windows (tested on WfW 3.11)

A player library for MSX music formats.

Miniplanets

A SN76489 emulator written in C.