[1] He is a Directeur de recherche at the CNRS and head of the team Max Modélisation algébrique at the Laboratoire d'informatique of the École Polytechnique.

[2] His research deals with transseries (i.e. generalizations of formal power series) with applications to algebraic analysis and asymptotic solutions of nonlinear differential equations.

In addition to transseries' properties as part of differential algebra and model theory, he also examines their algorithmic aspects as well as those of classical complex function theory.

He is the main developer of GNU TeXmacs (a free scientific editing platform)[3] and Mathemagix (free software, a computer algebra and analysis system).

In 2018, he was an Invited Speaker (with Matthias Aschenbrenner and Lou van den Dries) with the talk On numbers, germs, and transseries at the International Congress of Mathematicians in Rio de Janeiro.