As the author of this code in question, I'd like to make the offer to the Hacker News community and anyone at large. I'll do a live screen cast demonstration for interested persons and walk you through the entire compiler in 30 minutes to 1 hour. In the end you won't have a complete understanding of the compiler, but if you have reasonable prior programming experience, I claim that you will have a better, more full, and complete understanding of the compiler than if you had spent the same amount of time learning most other compiler designs. At that point, you would be able to continue your own self-study and would be able to start making contributions to the compiler rather quickly. This is an offer to demystify the code to people so that they have an opportunity to see how it really does make the whole compiler simpler and easier to work with.
If people express interest, I'll run such a live session and let people judge for themselves what they think of the code and my approach to "simplicity" after they've been introduced personally to the code base.