Planning of local wireless communication networks is about installing base stations (small radio transmitters) to provide wireless devices with strong enough signals. POPULAR is an advanced industrial prototype that allows to compute the minimal number of base stations and their location given a blue-print of the installation site and information about the materials used for walls and ceilings. It does so by simulating the propagation of radio-waves using ray tracing and by subsequent optimization of the number of base stations needed to cover the whole building. Taking advantage of state-of-the-art techniques for programmable application-oriented constraint solving, POPULAR is among the first practical tools that can optimally plan wireless communication networks.