giuliomoro, I'm using my own local makefile in the SPITest directory. I have a project with multiple platforms in the same git project, so I have a root folder with various IoT Projects, Mobile App projects, and the Bela project (HarmP1), then an example folder under it, and my test code underneath it. This example is in SPITest, in which I've just copied the render.cpp example to get start and try to build something. I was thinking that I could add a reference to a library for SPI?
Here's a culled down tree to give you some idea.