TypeScript Compiler API

Introduction

The book "TypeScript Compiler API" by David Sherret is a unique practical guide dedicated to working with the internal TypeScript compiler. Published in 2020, it spans 200 pages and is aimed at developers who want to create their own tools for static analysis, refactoring, and code automation. Despite being written in TypeScript, its concepts are also applicable to Python developers interested in metaprogramming and building code analyzers.

What the book is about

David Sherret, the well-known creator of the popular ts-morph library, thoroughly examines the architecture of the TypeScript Compiler API. The reader learns how the TypeScript compiler parses source code into an abstract syntax tree (AST), how to navigate tree nodes, modify them, and generate new code. The book covers topics such as working with types, creating custom transformers, writing linters, and integrating with existing build tools.

Who this book is for

The book is intended for developers already familiar with TypeScript (or JavaScript) who want to delve into metaprogramming. It will be useful for:

• creators of development tools (linters, formatters, code generators);
• developers maintaining large codebases in need of automatic refactoring;
• enthusiasts studying the internal workings of compilers;
• Python programmers interested in analogies with Python's AST (e.g., the ast module).

What the reader will learn

After reading the book, the reader will be able to:

• understand the structure of the TypeScript AST and ways to traverse it;
• use the Node and Symbol API for code analysis;
• create custom transformations (e.g., replacing function calls);
• write linters with custom rules;
• work with the compiler's type system (TypeChecker);
• integrate the API into command-line tools and bundler plugins.

Strengths

The main advantage of the book is its practical focus. Each chapter contains code examples that can be run immediately and adapted to one's own tasks. The author uses clear language, avoiding excessive academicism. Special mention should be made of the chapter dedicated to ts-morph — a library that simplifies working with the compiler. The book is well-structured: from basics to advanced techniques, allowing it to be used as a reference.

Who it is recommended for

Recommended for anyone who wants to go beyond simple TypeScript usage and start creating tools that automate routine tasks. For Python developers, the book will be an excellent introduction to metaprogramming in TypeScript and will also help better understand how similar mechanisms work in Python (e.g., the ast module and libraries like libcst).