<p>In a nutshell: OpenCPU is a layer on top of the regular tools (e.g. RApache, rpy2) that defines a framework and protocol for interacting with R. It handles stuff like object serialization, security, resource control, reproducibility etc, while abstracting away technicalities. </p>

<p>This <a href="http://arxiv.org/abs/1406.4806">paper on arxiv</a> goes into more detail on the motivation and design of the system and API.</p>
What's the intention of opencpu.org compared to other approaches?
<p>Lately I was pointed to <a href="http://opencpu.org/" rel="nofollow">http://opencpu.org/</a> . Nifty website, but after browsing for a little while I wasn't so sure where it is located in the R landscape compared to e.g. <a href="http://rapache.net/" rel="nofollow">rApache</a> or <a href="http://rpy2.bitbucket.org/" rel="nofollow">RPy2</a>.</p>

<p>After waiting a long time for the server to come back I was finally able to read the architecture section, but that wasn't too comprehensive. <strong>I'm looking for a more detailed explanation of what OpenCPU is, how it is intended to be used, and how this compares with existing tools such as <a href="http://rapache.net/" rel="nofollow">rApache</a> and <a href="http://rpy2.bitbucket.org/" rel="nofollow">RPy2</a>.</strong></p>