The code base for IsoplotR’s graphical user interface (GUI) and its core data processing algorithms are surgically separated from each other. The command-line functionality is grouped in a lightweight package called IsoplotR, which has minimal dependencies and works on a basic R installation. It only uses commands that have been part of the R programming language for many decades and are unlikely to change in the future. In contrast, the GUI is written in html and Javascript and interacts with IsoplotR via an interface library. This interface is currently provided by the shiny package. shiny is free, open, and popular among R developers but has two important limitations: (1) it was created and is owned by a private company, which reduces the software’s future proofness; (2) shiny is a rather ‘bloated’ piece of code that does much more than is needed for IsoplotRgui. To avoid these issues, shinylight is a light-weight alternative to shiny that allows websites to call R functions in a similar fashion to the way in which node.js allows websites to use Javascript as a server language. Shinylight has been integrated in IsoplotRgui and all future software deliverables of the ‘Beyond Isoplot’ project, including the upcoming 'simplex' program for SIMS data processing.
