Stevens formerly served the Raleigh, N.C., company as vice president of operating system, storage and clustering development, and has spent the past four years leading Red Hats enterprise strategy.
Stevens does not directly displace anybody at Red Hat.
"Mike Tiemann had the CTO title a couple of years ago, but no one has since then," Red Hat spokesperson Leigh Day told Ziff Davis Internet. "The function has been handled for a long while by a sort of task force, headed by Brian. This makes it official for him as CTO."
Tiemann currently is vice president of open-source affairs for Red Hat, which amounts to an evangelist-type position.
Stevens brings 20 years of enterprise engineering, including experience as the former CTO of Mission Critical Linux, where he was responsible for corporate strategy, business development, virtualization and the clustering product line.
As CTO, Stevens will focus on technology strategy and lead Red Hats Emerging Technologies group, the company said.
Prior to his position as CTO at Mission Critical Linux, Stevens spent 14 years at Digital/Compaq as a senior member of the technical staff, where he was an architect of the Tru64 Operating System and clustering products.
Stevens was a developer of the first commercial release of X Window System, as part of Project Athena, a joint venture of Massachusetts Institute of Technology and Digital Equipment Corp. He served as the technical lead and architect for the inaugural release of Digitals TruCluster product, which remains the industrys benchmark for clustered computing.
Stevens also holds a U.S. patent on secure methods of accessing computers through a firewall.
Stevens is based in Red Hats Westford, Mass., office.