Godot is a powerful cross-platform game engine
Enables Roblox developers to use professional software tools
One framework for creating powerful cross-platform games
A simple and easy-to-use library to enjoy videogames programming
Desktop/Android/HTML5/iOS Java game development framework
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
Open Source MMORPG Framework
Gideros Release version
ThinkPHP Framework
A game framework written with osu! in mind.
You can make it - Open Source MMORPG Platform
CTFs as you need them
Open source library for N64 development
Open source library for creative expression on the web, desktop, etc.
Unity3D Client And C# Server Framework
Self-hosted CMS platform based on the Laravel PHP Framework
lua dev plugin for unreal engine 4 or 5
Arianne is an engine to develop multiplayer online games like Stendhal
All-In-One program that combines multiple Fortnite Dev Account tools.
Ze Text Adventure game Builder : Create as you play !
Old-school 2D game engine
An isometric arcade-style game of skill, puzzles and exploration
INSTEAD - Simple Text Adventure Interpreter.