I took an interest in Werner Lemberg’s CJK/LaTeX in the 90’s while doing physics research. It was a slippery slope from there onwards, touching a fair number of projects on editing (emacs), displaying (various CJK terminals), typsetting, printing CJK characters (ghostscript), and printer drivers, and now Microsoft’s Font Validator.
I was trained as a research physicist and worked on magnetic and superconducting materials for just over a decade; worked as a telecom engineer, on network diagnostics for a while; then spent almost another decade as a data scientist on genetics of common diseases, specifically auto-immune diseases and Ophthalmology (i.e. eye problems). Taking on Font Validator is perhaps considered a 3rd diagnostics project of some sort.