Microsoft for years has been warning the world not to use open-source software. Apparently, its Kumo search team didn’t get the memo.

As The Register reports, Microsoft’s new Kumo search technology is filled with open source and, in fact, the Kumo search team, formerly Powerset, “tr(ies) to use open-source software, if it is available.”

In other words, open-source software appears to be the default choice for the Kumo team, not proprietary software. It looks like Microsoft’s anti-open-source bubble really has burst.

Indeed, reading through the Powerset-turned-Microsoft-Kumo team’s description of its approach reads like it was written by an open source-friendly IBM:

Instead of creating a proprietary copy of these pieces of infrastructure, Powerset decided instead to turn to Hadoop, a Lucene subproject that is a framework for running data-intensive applications on large clusters of commodity hardware…Unfortunately, there was no Hadoop equivalent to Google’s BigTable storage engine.

Because we have benefited greatly by leveraging the available Hadoop technology, Powerset decided to give back to the community by developing an open-source analog to BigTable that is built on top of HDFS (Hadoop Distributed File System). After all, we need to develop it, anyway, it isn’t part of the Powerset “secret sauce,” and we, in turn, could benefit from contributions from other members of the community.