I have written an R query runner and have been running that in our dashboard for a couple months now and it seems to work fine. It basically uses rpy2 to run R code and data is transferred as JSON strings between Python and R. Custom R functions are included to convert between R data frames and Redash’s JSON.
Is there interest in getting this included in Redash? If so, I could do a PR. The code is mostly ready, I’d just need to polish it a bit and generalize the installation of dependencies. Note that there’s no sandbox and I’m not interested in trying to hack that in, so it’d be an in your own installation at your own risk type of feature.