Since this project's objectives overlap with our work, we have contributed to its starting up with our participation, namely in detecting incompatibilities of available libraries, in analyzing the existing problems, in proposing a functional API, in this chapter, and in providing experimental results for the polyhedral domain. Our HQ interface is then discussed at APRON meetings where propositions, modifications are presented to obtain common decisions. From these decisions, a common interface is then proposed. The next section summarizes the decisions [APRa].