My own work in programming languages is mainly software verification.
 One of the tools I use for specification is type theory. I use the formal
 system <a href="http://www.cs.cornell.edu/Info/Projects/NuPrl/nuprl.html">Nuprl</a>,
 developed here at <a href="http://www.cs.cornell.edu/">the Cornell University
 Department of Computer Science</a>. In my research I make use of higher-level
 modules and abstract data types, and relate them to type-theory. </p>
