At the current time, most of my experience is using Godot Engine. If you have an OSS project and you need some help with it, go ahead and contact me! I'd like to stick to no more than 5 hours of work per week or so, but I am willing to work for free, so long as it's an open source project. I am also willing to offer tutoring, if you develop an OSS project and want guidance on one of the topis outlined above.