Operating systems (kernels, file system code); system architecture; language design, compilers, libraries, and related tools; networking in a hostile environment (such as the Internet); system administration; testing (quality assurance); and technical writing and editing.

Leadership/management roles; technical lead; scrum master; free-software advocate.

Experienced substantially improving productivity of software developers, testers, technical writers and editors, system administrators, and end users, via thoughtful analysis of workload, process, and quality controls, followed up with research, proposal, development, implementation, and maintenance.

See my résumé for further details.