In one example in accordance with the present disclosure, a fluid ejection die is described. The fluid ejection die includes a fluid feed slot to deliver fluid from a reservoir to an array of ejection chambers fluid connected to the fluid feed slot. Each ejection chamber includes at least one fluid actuator and an opening through which fluid is to be ejected. The fluid ejection die also includes a number of antechambers. An antechamber includes sidewalls that curve inward.