fheroes2 is a recreation of Heroes of Might and Magic II game engine
The game engine for everyone
lua dev plugin for unreal engine 4 or 5
A lightweight game server framework implemented with Actor Model
3D Scene Builder
Vivid is a modern C++ 3D engine using OpenGL4+
The Old PacMan! programed over the Salvat Game Fabric platform
3D Game engine
C++ game libraries plus server.
TurboSphere is an easy to learn and powerful JS based game engine.
C++ Framework for slot machine games
A simple telnet (and possibly SSH) server
BxEngine For Marmalade And QT
Tactical, turn-based game engine, that uses OpenGL and WinAPI