It's been possible to run R code in the browser for a while now, thanks to webR. It comes with both the browser-based R interpreter and webR binary package repository.
DESeq2 and other Bioconductor packages, however, aren't currently available in webR's binary repository, so to run DESeq2 in the browser, I had to compile DESeq2 and its dependencies manually to the format required by webR.
DESeq2 is a Bioconductor package for differential gene expression analysis. Its source code is written in R and C++ and is available on GitHub.
Below is the demo of the result—DESeq2 running fully in the browser. It calculates differential gene expression between two groups of samples and displays the summary of the results.