Muffin

Muffin is a window and compositing manager that displays and manages

your desktop via OpenGL. Muffin combines a sophisticated display engine

using the Clutter toolkit with solid window-management logic inherited

from the Metacity window manager.

While Muffin can be used stand-alone, it is primarily intended to be

used as the display core of a larger system such as Cinnamon.

For this reason, Muffin is very extensible via plugins, which

are used both to add fancy visual effects and to rework the window

management behaviors to meet the needs of the environment.