&gt;Geode and its predecessor GemFire are pure Java.<p>i know (was talking at some point about joining, already here in SV), and this is why i wrote only  &quot;3 decades&quot; as i don&#x27;t know precise dates of GemFire only suppose it to be beginning of 200x. My simple arithmetics mistake though - 2002 - 1982 is 2 decades, sorry, i see where confusion comes from :)