Numerical simulation is more and more widely used for the design of new products thanks to the increasing cost of testing grounds and the improvement of technologies. As example, it allows to determine the evolution of an equipment (for example a nuclear reactor) during its lifespan. To be able to achieve realistic results, numerical simulation codes need to rely on new computer related technologies (both in software and hardware areas) to face their important challenges. Salom?e is a platform whose goal is to carry out these studies while providing a way to integrate different codes into the same numerical framework. This paper describes the programming model offered by the platform to integrate numerical codes.