600 lines of code really isn't that much. At my day job a single file can be 2-6x that long, and there are a lot of files to deal with. Any project that gets beyond "Hey here's a neat little snippet of code that does something" will very quickly begin to dwarf those 600 lines. Also, from the original post talking about the new API and current graphics drivers, every developer is already implicitly using a couple million lines of code by using the OpenGL/DirectX APIs. They're just hidden from the developer in a closed-source binary.