Show HN: I just published my practical guide to building a database server (leanpub.com)

Hi all, I've just published my first book on Leanpub. The book is a guide to building your own database server that is similar to PostgreSQL or MySQL. You'll find out about how to build a typed programming language, execute SQL and learn how the internals of real databases work.

The page links to the 'community edition' which lets you see a free preview of the first few chapters.