My general area of interest is applied logic: the study of mathematical and conceptual tools for use in computer science, linguistics, artificial intelligence and other areas. Here are a few of my current areas:

Coalgebra, and more generally: circularity in mathematics and computer science.

Modal logic, its generalizations and applications.

Foundations of the theory of recursion.

Mathematics of language.

Finite graphs which are universal for sets of isometric embeddings.