WebR - R in the Browser

This project aims to compile the statistical language R (https://www.r-project.org/) into WASM for use with a browser, via Emscripten (https://emscripten.org/).

Documentation

Documentation showing how to use webR in your own projects can be found at https://docs.r-wasm.org/webr/latest/

Downloading webR

The webR JavaScript package is available for download through npm and on CDN.

Complete release packages, including R WebAssembly binaries, are available to download for self hosting in the GitHub Releases section.

Building webR from Source

Included in the source repository is a Dockerfile which can be optionally used to setup an environment and toolchain for compiling R's source code and supporting libraries, written in both C and Fortran. If you are compiling webR without Docker, ensure that you first have the Emscripten SDK installed, along with some required prerequisites:

• cmake
• wget
• quilt
• liblzma
• libpcre2
• node (>=16.0.0)

R's Fortran source files can be compiled with either a custom development version of flang (the default) or with gfortran and Dragonegg (using the --with-dragonegg configure option).

The repo includes patches for R's source code so that it can work in the browser environment provided by Emscripten. The patches also tweak R's interactive mode so as to provide a web-based REPL through the use of xterm.js.

Build Instructions

Clone the repo into a new directory, cd into the directory, then run ./configure && make. You can configure make variables in a ~/.webr-config.mk file.

A dist directory is created which when finished contains the R WASM files and an index.html file ready to serve an R REPL.

Building on macOS Ventura 13.0+

At the time of writing the version of R used as the base for webR does not build cleanly using the macOS Ventura development SDK. If you are not using the included Dockerfile to build webR, the following extra setup must be done before starting the build process,

• Install the GNU version of the patch program: e.g. brew install gpatch

Demo

A demo of the resulting R REPL can be found at https://webr.r-wasm.org/latest/

Please be patient as the WASM runtime downloads and executes. R will display a banner message when it is ready to use.