An initiator assembly for a perforating gun includes a detonator configured to detonate a shaped charge of the perforating gun when ballistically coupled to the shaped charge, wherein the detonator includes a detonator housing that receives an explosive material and a detonator electrical connector extending from the detonator housing, and a switch assembly configured to detonate the detonator after receiving a firing signal, wherein the switch assembly includes a switch housing and a switch electrical connector received in the switch housing, wherein one of the detonator electrical connector and the switch electrical connector is insertable into the other of the detonator electrical connector and the switch electrical connector to form an electrical connection between the detonator and the switch assembly.