BizHawk is a multi-system emulator written in C#
MAME is a multi-purpose emulation framework
A fast and reliable entity component system (ECS) and much more
Powerful, fast and developer-friendly extension framework
Arianne is an engine to develop multiplayer online games like Stendhal
JavaScript framework to build game engines, games, emulators and apps
Cerberus Content Management System
Flexible, extensible, and scalable video game matchmaking
Lightweight, facility, high performance golang based game server
A Rust framework for building Minecraft servers
A continuation of the popular Artemis ECS framework
MMORPG
Asphyre is a cross-platform framework for Delphi and FreePascal.
The Pokemon Go Bot, baking with community
Lightweight framework for old-school RPG GUI in web!
Make robots for MediaWiki-powered sites!
A Flash Molehill (Stage3D) GPU accelerated 2D game engine
ONUSystem is A module-based framework for games and CG arts.
C++ Framework for slot machine games
Cross platform 2D game creation framework with Python bindings
StarlingPunk is a framework built on top the Starling library