Author here, I found it pretty interesting the amount of similarity between BPF and embedded development. My original background is in computer design and low-level software, so this was a bit of a blast from the past - lots of delicately holding the compiler in just the right way to get it to emit the desired set of instructions, reading through the resulting assembly (_much_ easier with the validator annotating register values), digging deep into language specs and compiler documentation. It makes sense in retrospect, but it caught me off guard when I first started.
Let me know if you have any questions.