<li>programning language-agnostic (parts and different implementations in <ahref="http://golang.org/">Go</a>, Python, Java, Perl, Bash, ... the language doesn't matter.) What matters is well-defined, simple HTTP interfaces.</li>
<li>neither "Cloud" nor "Local". happily both.</li>
<li>a "20% project" from a few Google employees, but not Google-centric nor endorsed by Google (other than them letting us open source our side project)</li>