If I read the article right the main questions are: What is the simplest self reproducing system? What are the parameters needed for such a system? Can such

If I read the article right the main questions are: What is the simplest self reproducing system? What are the parameters needed for such a system? Can such a system lead to an evolution cycle? I like the approach he lays out. I've always been curious about what it would take to write a simulation where the evolution happens in code space instead of attribute space.