GDPong uses the Godot Engine, which is a fully open-source, modern, game engine capable of 2D and 3D scene generation. In the case of this particular project, Godot is using the GDExtension feature to execute game code written using Rust, instead of the proprietary GDScript scripting language.
The implementation of this Pong remake uses resources that are publicly available:
Thanks to these resources, anyone can easily start implementing their game using Godot Engine and its Rust binding features.