STACK Engine is a free and open .NET framework dedicated to create 2D point & click graphic adventure games for desktop PCs. While being currently under development, its source code is already hosted at GitHub.
'Session Seven' is the first game using STACK and is also under active development. It will be open source and released for free. Expected release date is 2018.
The engine's features were chosen carefully to make development of point & click adventures as easy and comfortable as possible while not getting in the way of the developer. Any game logic is written in C# enabling the broad range of .NET's capabilities. Great value was placed on having a testable architecture which allows to write tests that solve your whole game within just a fraction of a second and giving you immediate feedback if something doesn't work as expected.