Stefan works on QEMU and Linux in Red Hat's Virtualization team with a focus on storage, VIRTIO, and tracing. Recent projects include libblkio, virtiofs, storage performance optimization for NVMe drives, and out-of-process device emulation. Stefan has been active in the QEMU community since 2010 and has presented at KVM Forum, FOSDEM, and other open source conferences. He also organizes and mentors in QEMU's Google Summer of Code and Outreachy internships.