Schematic relations between solid disk mass, core ice, and system architecture. (a) A disk with just enough solid material (M_solid ~ 100 M_⊕) to grow super-Earth cores will produce them preferably right behind the water ice line. The emerging ice-rich planets remain of too low mass to trigger runaway gas accretion and migrate freely to inner orbits where they can be detected. (b) A more massive disk (M_solid ≳ 200 M_⊕) provides theconditions for giant planet formation, which again happens predominantly just beyond the ice line. The gas giant then blocks the migration of ice-rich cores that formed further out. However, the disk allows also for growth of dry super-Earths on closer orbits. In this scenario, the existence of super-Earths with high bulk densities is a proxy for giant planets in the same system.