· Principal Researcher, Microsoft2019–
· Principal Engineer, Amazon2017–2019
· Xen Maintainer, Citrix Systems2011–2015
· Software Architect, Coho Data2011–2017
· Principal Software Engineer, Citrix Systems2007–2011
· Senior Engineer, XenSource2006–2007
· Ph.D. Computer Science, University of Cambridge2002–2006
· Ph.D., Computer Science, University of Cambridge2002–2006
· Secure Hosting Systems Administrator, Baltimore Technologies2001–2001
· Research Assistant Ph.D. Student, University of Cambridge2001–2006
· Technical Hostmaster, .IE TLD, University College Dublin2000–2000
· B.A., Computer Science, University of Cambridge1995–1998