{The lineage and progeny of fontspec and~\hbox{unicode-math}} {Will Robertson} {My first \LaTeX\ package, \code{fontspec}, was written in 2004 before I knew how to program in \LaTeX\ and in truth before I knew how to program at all. This trial-by-fire introduced me to the lovely world of \TeX\ programming and after some time I ended up writing a smattering of other works. (All the while actually starting to learn what this whole `programming' thing was all about, including how to please and displease people who were just trying to get work done, thank you very much.) Some time later I foolishly tried `planning' an ambitious new package, \code{unicode-math}, that took significantly longer to release. In the course of writing that package I learned really just how little I actually knew, and as a side-effect somehow ended up helping to write code for the \LaTeX3 project. In this talk I will talk about the motivation for writing these two packages, discuss recent developments with them, and finally touch on how \LaTeX3 influenced their development. }