Great book for learning OOP and how to implement a bytecode compiler and interpreter for a small language. One of my favorite books.

A few years later Budd worked on a successor where the compiler and much of the system was written in Smalltalk and image-based. Only the VM was in C: stop and copy garbage collection, bytecode interpreter and primitives. Small and straightforward. A wonderful system for learning how to implement languages.

Sources to several versions: https://github.com/crcx/littlesmalltalk