Substrates, assemblies, and techniques for enabling multi-chip flip chip packages are disclosed herein. For example, in some embodiments, a package substrate may include a first side face; a second side face, wherein the second side face is opposite to the first side face along an axis; a portion of insulating material extending from the first side face to the second side face; wherein a cross-section of the portion of insulating material taken perpendicular to the axis has a stairstep profile. Solder pads may be disposed at base and step surfaces of the portion of insulating material. One or more dies may be coupled to the package substrate (e.g., to form a multi-chip flip chip package), and in some embodiments, additional IC packages may be coupled to the package substrate. In some embodiments, the package substrate may be reciprocally symmetric or approximately reciprocally symmetric.