Textbook in PDF format

Turn your R code into packages that others can easily install and use. With this fully updated edition, developers and data scientists will learn how to bundle reusable R functions, sample data, and documentation together by applying the package development philosophy used by the team that maintains the "tidyverse" suite of packages. In the process, you'll learn how to automate common development tasks using a set of R packages, including devtools, usethis, testthat, and roxygen2.
Authors Hadley Wickham and Jennifer Bryan from Posit (formerly known as RStudio) help you create packages quickly, then teach you how to get better over time. You'll be able to focus on what you want your package to do as you progressively develop greater mastery of the structure of a package.
Packages are the fundamental units of reproducible R code. They include reusable R functions, the documentation that describes how to use them, and sample data. In this book you’ll learn how to turn your code into packages that others can easily download and use. Writing a package can seem overwhelming at first. So start with the basics and improve it over time. It doesn’t matter if your first version isn’t perfect as long as the next version is better.
Ideal for developers and data scientists, this book gets you creating packages ASAP, then shows you how to get progressively better over time. You'll learn to focus on what you want your package to do, rather than thinking about package structure.
This book espouses our philosophy of package development: anything that can be automated, should be automated. Do as little as possible by hand. Do as much as possible with functions. The goal is to spend your time thinking about what you want your package to do rather than thinking about the minutiae of package structure. This philosophy is realized primarily through the devtools package, which is the public face for a suite of R functions that automate common development tasks.
With this book, you will:
Learn the key components of an R package, including code, documentation, and tests
Streamline your development process with devtools and the RStudio IDE
Get tips on effective habits such as organizing functions into files
Get caught up on important new features in the devtools ecosystem
Learn about the art and science of unit testing, using features in the third edition of testthat
Turn your existing documentation into a beautiful and user friendly website with pkgdown
Gain an appreciation of the benefits of modern code hosting platforms, such as GitHub