Writing a compiler sounds scary to some people. It's not scary. The only compilers training I have is a senior-year undergraduate course, and quite a lot of that was learning all the different ways to write parsers. Wasabi uses a LL(k) recursive descent parser, and you don't have to know what that means to be able to work on it. I've never even read the Dragon book; we used Cooper & Torczon "Engineering a Compiler" instead.