styler packagescale()Packages are the fundamental unit of reproducible code in R. Most of the time, we as practitioners simply use packages that have been provided by others. However, sometimes, when we have developed a methodology that others might find useful, it may be advantageous to write our own R packages and share them with the community. Writing an R package involves creating a directory with a specific structure and adding code, documentation, and package metadata in a way that allows it to be distributed.
Hadley Wickham and Jenny Bryan have written an excellent book on how to write R packages. If ever you need to write your own R package, this should be the only place you need to go.