Arqan is an OpenGL library I wrote a long time ago. It basically pInvokes all OpenGL functions from c++ and converts it to a C# method. Both a Linux and Windows version is available as well as bindings to the popular GLFW library.
Together with another GitHub user, DelightedCat, we developed a dotnet standard library for parsing Tiled maps and tilesets. I created the library itself and DelightedCat created a custom MonoGame pipeline as it happens to be a much requested feature on the internet. This library was created to replace TiledSharp, which is now one of the most popular Tiled parsing libraries for C#. The owner is no longer interested in maintaining his library and since it is roughly outdated we agreed to create a new one from scratch (which was not that difficult anyway). Also, unlike Tiled.NET, TiledCS supports Tiled maps in JSON format.