From TFA:

Do you think that PRISM can be built using a different tech stack?

From https://en.wikipedia.org/wiki/Apache_Accumulo :

Apache Accumulo is a sorted, distributed key/value store based on Google's BigTable design. It is a system built on top of Apache Hadoop, Apache ZooKeeper, and Apache Thrift. Written in Java, Accumulo has cell-level access labels and server-side programming mechanisms.

Accumulo was created in 2008 by the National Security Agency and contributed to the Apache Foundation as an incubator project in September 2011.