Get the speed and reliability of Rust libraries, functions, and high-performance features through incremental adoption without rewriting your codebase from scratch. Refactoring to Rust teaches you how to take advantage of Rust's easy-to-use interoperating mechanisms. Learn practical code-mixing techniques like embedding Rust libraries into apps written in other languages. This practical guide emphasises techniques for incrementally refactoring performance-critical code to Rust while keeping the rest of your application in its original language. Rust is one of the most exciting new languages out there. Consistently rated as the "most loved" language by the Stack Overflow developer survey, many developers wonder what about Rust makes its users so happy. In our development jobs, it can be difficult to get management buy-in to start up a new service around a language that may never have been used at the company before. Instead, replacing a small part of performance-critical code with Rust might be a more effective first project. This book intends to give you the tools and skills required to make a surgical refactoring like this possible. The chapters in this book will take you through the areas where Rust differs the most from other languages, introduce you to embedding Rust within a C program, using the Py03 library to embed Rust in Python, as well as testing, profiling, and monitoring your refactored code to ensure that it's performing within expectations. Refactoring to Rust is intended for developers that have some familiarity with Rust already.