This chapter explains how to structure larger R/C++ projects. In particular, we start by explaining how C++ code divided into several files can be compiled and loaded using Rcpp::sourceCpp. For larger projects, and especially projects that must be shared with other people, this way of working is not ideal and building an R package containing your R and C++ code is much preferable. Hence, the bulk of this chapter is dedicated to explaining how to:

• use Rcpp to build R packages that contain C++ code;
• use C++ code from other packages;
• make C++ code available to other packages.

The chapter consists of the following sections:

• 1. Building larger Rcpp programs
• 2. Using Rcpp in an R package (1)
• 3. Using Rcpp in an R package (2)