A microelectronic package can include a substrate having first and second opposed surfaces extending in first and second transverse directions and an opening extending between the first and second surfaces and defining first and second distinct parts each elongated along a common axis extending in the first direction, first and second microelectronic elements each having a front surface facing the first surface of the substrate and a column of contacts at the respective front surface, a plurality of terminals exposed at the second surface, and first and second electrical connections aligned with the respective first and second parts of the opening and extending from at least some of the contacts of the respective first and second microelectronic elements to at least some of the terminals. The column of contacts of the first and second microelectronic elements can be aligned with the respective first and second parts of the opening.