The development of an open-source code for the multidisciplinary design optimization related to the aero-structural optimization of wings is presented. This work is the result of a series of studies done thanks to the cooperation of ISAE and ONERA. The aim of this work is to develop an optimization process able to maximize the performance of a wing modifying its geometry out of respect of the constraints imposed, considering the aeroelastic coupling between aerodynamics loads and structural displacements. In order to manage a huge number of constraints, a constraint aggregation method is presented, based on the Kreisselmeier-Steinhauser function. It’s also presented a reduced model in relation to the aeroelastic coupling in order to reduce the computational cost.