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
Desktop/Android/HTML5/iOS Java game development framework
One framework for creating powerful cross-platform games
Real Time Strategy game engine supporting early Westwood classics
Open source HTML5 game framework that offers WebGL and Canvas
Fast and lightweight JavaScript game engine built on WebGL and glTF
Gideros Release version
Open Source MMORPG Framework
CTFs as you need them
Self-hosted CMS platform based on the Laravel PHP Framework
Unity3D Client And C# Server Framework
ThinkPHP Framework
You can make it - Open Source MMORPG Platform
lua dev plugin for unreal engine 4 or 5
Open source library for creative expression on the web, desktop, etc.
A game framework written with osu! in mind.
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
Old-school 2D game engine
Game engine supporting many 3D/2D formats and graphic effects
An isometric arcade-style game of skill, puzzles and exploration
SDL based generic 2D game engine