• The Inria's Research Teams produce an annual Activity Report presenting their activities and their results of the year. These reports include the team members, the scientific program, the software developed by the team and the new results of the year. The report also describes the grants, contracts and the activities of dissemination and teaching. Finally, the report gives the list of publications of the year.

• Legal notice
• Personal data

## Section: New Results

### Extension language for Coq

Participants : Enrico Tassi, Feruccio Guidi [University of Bologna] , Claudio Sacerdoti Coen [University of Bologna] .

We continued our work on the design of a language mixing $\lambda$-prolog and constraint programming. This year, we redesigned and provided a new implementation of the constraint handling rules, leading to a first public release of the software. We are starting to have users beyond our own team:

In an article submitted for publication [24], we showed that Elpi could be used to give a short implementation of Type Theory.

We are also starting a collaboration to construct an elaborator for HOL-Light using Elpi.