Godot is an open source 2d/3d game engine has just released new beta version!
Godot-d is a bindings for Godot, latest official release is for Godot 3 only, however here is a WIP branch for Godot 4 latest beta-4.
Original godot-d issue on GitHub about Godot 4 support
For getting started see this document
Currently godot4 branch is purely experimental WIP project as stated in the document, so do not expect to ship real product with that, even more nor Godot 4, nor godot-d is not ready for that.