Mark is the co-author of O'Reilly's Hadoop Application Architectures book, a committer on Apache Bigtop and a committer and PMC member on Apache Sentry (incubating). He has contributed code to Apache Hadoop, Apache Hive, Apache Sqoop and Apache Flume projects. He is also a section author of O'Reilly's book on Apache Hive – Programming Hive. He currently works as a Software Engineer at Cloudera.