The goal of our research is to computationally design materials with desired properties for target applications. Through the portal of computer simulations we gain access to the vast configuration space of materials structure and composition. We can explore the uncharted territories of materials that have not been synthesized yet and predict their properties from first principles, based solely on the knowledge of their elemental composition and the laws of quantum mechanics. Since the Schrödinger equation can be solved exactly only for very small systems (=the hydrogen atom), we employ approximate methods within the framework of density functional theory (DFT) and many-body perturbation theory (MBPT) to apply quantum mechanics to complex atomic systems with up to several hundred atoms. To navigate the configuration space we use genetic algorithms, guided to the most promising regions by the evolutionary principle of survival of the fittest. The computational cost of quantum mechanical simulations increases rapidly with the accuracy of the method, the size of the system, and the number of trial structures sampled, therefore we run our calculations on some of the world’s most powerful supercomputers.