The Saladyn software toolbox is the main outcome of the ANR project Saladyn (COSINUS ANR-08-COSI-014-01), which aims at designing and implementing a new software platform by coupling several kinds of mechanical models and modeling approaches in a single framework : a) solid bodies (deformable), mainly through their finite element representation, b) rigid multi-body systems and c) multi-contact systems. The goal is to obtain a close coupling of these models for the modeling and the simulation in a nonsmooth dynamical framework, able to deal rigorously with the unilateral contact and Coulomb's friction. This platform is composed of the integration of the following components: SALOMÉ, an open-source platform for the pre and post-processing and the coupling of numerical software codes, CODE_ASTER an open-source Finite Element Application, which has already been integrated in Salomé, under the name of Salomé-méca, LMGC90 an open-source software for the modeling and the simulation of multi-contact systems and SICONOS an open-source software for the modeling, the simulation and the control of nonsmooth dynamical systems. In this article, the common formalism and numerical methods are delineated. Several general coupling schemes are described and the interest of the approach is illustrated on several industrial realistic examples.