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
Desktop/Android/HTML5/iOS Java game development framework
One framework for creating powerful cross-platform games
Open source HTML5 game framework that offers WebGL and Canvas
Fast and lightweight JavaScript game engine built on WebGL and glTF
Open Source MMORPG Framework
lua dev plugin for unreal engine 4 or 5
ThinkPHP Framework
CTFs as you need them
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.
Gideros Release version
Unity3D Client And C# Server Framework
Self-hosted CMS platform based on the Laravel PHP Framework
All-In-One program that combines multiple Fortnite Dev Account tools.
Arianne is an engine to develop multiplayer online games like Stendhal
Orx: Portable Game Engine
Game engine supporting many 3D/2D formats and graphic effects
JavaScript framework to build game engines, games, emulators and apps
Amateur 3D Game Engine
Ze Text Adventure game Builder : Create as you play !