UCI chess engine
Compatibility tool for Steam Play based on Wine and other components
RetroArch is a frontend for emulators, game engines and media players.
Real Time Strategy game engine supporting early Westwood classics
C# application with primary purpose of farming Steam cards
A Native GOG and Epic Games Launcher for Linux, Windows and Mac
Free and open source real-time strategy game
Fast and lightweight JavaScript game engine built on WebGL and glTF
Open Source MMORPG Framework
Endless Sky is a sandbox-style space exploration game
Distributed server for social and realtime games and apps
Open source Old School RuneScape client
Flexible level editor
A charting and data visualization library for Unity
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Open Source real-time strategy game engine for early Westwood games
New Modpack with Gregtech, Thaumcraft and Witchery
Build multiplayer web games played by millions
Widelands is a free, open source real-time strategy game
Games for tomorrow's programmers
Moonlight port for Nintendo Switch
Voxel game engine in C++ with OpenGL
The flexible game engine
A sharp, readable, vector-y version of Monocraft
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D