Build Your Own Lisp by Daniel Holden.
From the webpage:
If you’re looking to learn C, or you’ve ever wondered how to build your own programming language, this is the book for you.
In just a few lines of code, I’ll teach you how to effectively use C, and what it takes to start building your own language.
Along the way we’ll learn about the weird and wonderful nature of Lisps, and what really makes a programming language. By building a real world C program we’ll learn implicit things that conventional books cannot teach. How to develop a project, how to make life easy for your users, and how to write beautiful code.
This book is free to read online. Get started now!
This looks interesting and useful.
Enjoy!