Desktop/Android/HTML5/iOS Java game development framework
Godot is a powerful cross-platform game engine
A simple and easy-to-use library to enjoy videogames programming
Enables Roblox developers to use professional software tools
Real Time Strategy game engine supporting early Westwood classics
One framework for creating powerful cross-platform games
Open Source MMORPG Framework
Open source HTML5 game framework that offers WebGL and Canvas
Gideros Release version
Fast and lightweight JavaScript game engine built on WebGL and glTF
lua dev plugin for unreal engine 4 or 5
A game framework written with osu! in mind.
You can make it - Open Source MMORPG Platform
Open source library for creative expression on the web, desktop, etc.
ThinkPHP Framework
CTFs as you need them
Self-hosted CMS platform based on the Laravel PHP Framework
Arianne is an engine to develop multiplayer online games like Stendhal
Game engine supporting many 3D/2D formats and graphic effects
A complete 2D/3D Arcade Game Engine for Browser (Blender compatible)
INSTEAD - Simple Text Adventure Interpreter.
Old-school 2D game engine
PyCAPGE - Python Classic Adventure Point and Click Game Engine
JavaScript framework to build game engines, games, emulators and apps
Orx: Portable Game Engine