{Star \TeX, the Next Generation}
{Didier Verna}
{In 2010, I asked Donald Knuth why he chose to design and implement \TeX\ as a
macro-expansion system (as opposed to more traditional procedure calls). His
answer was that:
1)~he wanted something relatively simple for his secretary who was not a
   computer scientist;
2)~the very limited computing resources at that time practically mandated the
   use of something much lighter than a true programming language.

The first part of the answer left me with a slight feeling of skepticism. It
remains to be seen that \TeX\ is simple to use, and when or where it is, its
underlying implementation has hardly anything to do with it.

The second part of the answer, on the other hand, was both very convincing and
arguably now obsolete as well. Time has passed and the situation today is very
different from what it was 30 years ago. The available computing power has
grown exponentially, and so has our overall skills in language design and
implementation.

Several ideas on how to modernize \TeX\ already exist. Some have been actually
implemented. In this talk, I will present mine. Interestingly enough, it seems
to me that modernizing \TeX\ can start with grounding it in an old yet very
modern programming language: Common Lisp. I will present the key features that
make this language particularly well suited to the task, emphasizing on points
such as extensibility, scriptability and multi-paradigm programming. The
presentation will include reflections about the software engineering aspects
(internals), as well as about the surface layer of \TeX\ itself. Most notably, I
will explore the possibilities of providing a more consistent syntax to the
\TeX\ \acro{API}, while maintaining backward compatibility with the existing code base.
}