I was curious after you said this, so I took a look at the 4coder source. It looks like very straightforward code. The files are clearly marked so you know exactly what they do, the APIs look simple and reasonable, and they have clearly marked folders containing all platform specific code. I'm not sure why you put this side note here, but it doesn't seem to hold water in this case. The code is definitely not spaghetti, and it looks like it was designed with quite a bit of forethought.
Edit: I would just like to add that I saw the author left several comments about the state of the code in the Readme that imply the code is very unstable. I think developers tend to be very critical of their own code, but when I took a cursory glance at the code from an outside perspective it seems much easier to follow then many other projects I've tried to take a look at. For example, for a quasi-open source project, ffmpeg is extraordinarily complex and hard to follow. So I definitely don't think OSS = super well designed code haha