Part of Yahoo's Sunnyvale, Calif., Hadoop 100-plus team of software engineers and researchers who continue to develop Hadoop, now an open source project at the Apache Software Foundation. The Yahoo production version of Hadoop is also freely distributed, and is considered one of the best production-ready versions of the code. Yahoo! staffers make up the largest set of contributors to Hadoop. Originator Doug Cutting, who named Hadoop for his son's toy elephant, now works at Cloudera.