You can make it - Open Source MMORPG Platform
Godot is a powerful cross-platform game engine
Desktop/Android/HTML5/iOS Java game development framework
Open Source MMORPG Framework
One framework for creating powerful cross-platform games
A simple and easy-to-use library to enjoy videogames programming
Self-hosted CMS platform based on the Laravel PHP Framework
A game framework written with osu! in mind.
Real Time Strategy game engine supporting early Westwood classics
Open source library for creative expression on the web, desktop, etc.
Gideros Release version
All-In-One program that combines multiple Fortnite Dev Account tools.
INSTEAD - Simple Text Adventure Interpreter.
Game engine supporting many 3D/2D formats and graphic effects
JavaScript framework to build game engines, games, emulators and apps
2D Game Engine
A cross platform Lua based game engine
A real-time game development platform
Cross-platform 2D and 3D game engine
Example code for creating a 2D platform game in Java.
Build Cross-platform Applications
The Old PacMan! programed over the Salvat Game Fabric platform
Asphyre is a cross-platform framework for Delphi and FreePascal.