Godot is a powerful cross-platform game engine
Enables Roblox developers to use professional software tools
A simple and easy-to-use library to enjoy videogames programming
Real Time Strategy game engine supporting early Westwood classics
Open game and rendering engine packed into a JavaScript framework
Open Source MMORPG Framework
Fast and lightweight JavaScript game engine built on WebGL and glTF
Desktop/Android/HTML5/iOS Java game development framework
Open source HTML5 game framework that offers WebGL and Canvas
One framework for creating powerful cross-platform games
ThinkPHP Framework
A game framework written with osu! in mind.
You can make it - Open Source MMORPG Platform
Open source library for N64 development
Self-hosted CMS platform based on the Laravel PHP Framework
CTFs as you need them
Gideros Release version
Open source library for creative expression on the web, desktop, etc.
Arianne is an engine to develop multiplayer online games like Stendhal
Game engine supporting many 3D/2D formats and graphic effects
Orx: Data-Driven Game Engine
utility collection for 2D game development in Java; sound-player
Game/Scene Development System
Old-school 2D game engine
lua dev plugin for unreal engine 4 or 5