The plumber package for R makes it easy to expose existing R code as a webservice via an API (https://www.rplumber.io/, Trestle Technology, LLC 2017).
You take an existing R script and make it accessible with plumber by simply adding a few lines of comments. If you have worked with Roxygen before, e.g. when building a package, you will already be familiar with the core concepts. If not, here are the most important things to know:
