DOS
Operating system for x86-based personal computers that was popular during the 1980s and early 1990s.
Contents
Development tools
GitHub fork which is actively maintained and is ported to 64-bit Windows and Linux.
Portable self-hosting C compiler capable of producing executables for a number of platforms, including real and protected mode DOS programs, by Alexei A. Frounze.
A self-hosting Small-C Compiler Toolkit for DOS(8086) with: K&R C Compiler, Make, Linker, Assembler. First released in 1982 by Jim E. Hendrix.
Memory manager for DOS PCs with 386 or higher CPUs, released by Qualitas company in 1992. Source code was released in June 2022 on GitHub with GPL-3.0 license.
Source code
Open source DOS libraries
Game development library for DOS, Windows and Linux. 4.2 version supports DOS platform.
A framework for making 2D DOS games in Lua. API based on a subset of the LÖVE API.
Open source DOS games
Homebrew games with source code
Christopher Wellons's x86 real mode DOS Asteroids clone created as an entry for Lundum Dare #31.
First-person 2.5D dungeon-crawler on protected mode. Written in C++, includes software rendering, fixed point math, test coverage and sound (PC speaker, Adlib, OPL2LPT).
Flappy Bird clone written in 16 bit assembly. Not a DOS program, but a PC-Booter application instead (although it's also possible to build a COM executable for DOS).
'80s style arcade shooter written in Quickbasic. Also the very first known DOS game that supports Oculus Rift VR headset.
Descendant of the original NetHack rougelike game first released in 1987 available on multiple platforms.
Gomoku clone written in C. Works on DOS, ZX Spectrum, ZX81, ZX80, APPLE1, AS400 and Windows.
Overhead puzzle game written in C. Web version uses DOSBox ported to Emscripten to embed DOSBox into HTML5. However, the original executable is also downloadable and buildable with Open Watcom.
Tetris clone written in C. Runs on DOS, Unix/Linux, ZX Spectrum and Windows.
Commercial games with published source code
2D top-down shooter developed by Softdisk (later becoming id Software). Supports EGA and CGA graphics. Written in Turbo Pascal and assembly.
First-person shooter in fantasy setting developed by Softdisk (later becoming id Software). Features pseudo-3D graphics with raycasting technique. Supports EGA graphics. Written in C and assembly. Compiled with Borland C++ 3.1.
Side-scrolling platform game developed by id Software. Keen Dreams is the Commander Keen game created between Keen 3 and Keen 4 (often considered "Keen 3.5"), but was not widely released. Written in C and assembly.
First sci-fi FPS/space shooter to feature entirely true 3D graphics. Written in C and assembly.
Sci-fi FPS developed by id Software where you fight demons from hell on Mars. The DOS-specific code for Doom could not be published because of a dependency to the licensed DMX sound library, hence why it's cleaned up and only the Linux source is there. However, the Heretic and Hexen projects contain the original DOS code in a way where DMX-related code is removed.
FPS developed by id Software. Features pseudo-3D graphics with raycasting technique, before Catacomb 3D and Wolfeinstein 3D. Written in C and assembly.
FPS developed by id Software set in the fully 3D world. Written in C. Compiled with DJGPP for DOS.