Hi @Bluescreen
I think what you want to do is perfectly reasonable, but you need to recognize that it is not “impedance matched” to what Spark is all about, so you will have some frustrations here. For example, as @mdma said, where should puts() send its output? The entire infrastructure you are assuming when you write puts() has not been written for this platform–there is no kernel.
Have you tried a Raspberry Pi? It seems like a much better fit to your mental programming model.
Also there is/was a NuttX port for the core: