Ocular surgery may be performed by a variety of systems, processes, and techniques. In certain implementations, systems and processes for ocular surgery may include the ability to emulsify a lens in an eye using a modular hand-held system including a phacoemulsification unit detachably coupled to a pump unit and remove lens portions from the eye using suction provided by the pump unit. The system and the process may also include the ability to decouple the phacoemulsification unit from the pump unit, couple an irrigation-aspiration unit to the pump unit to form a second hand-held system, and remove material from the eye using suction provided by the pump unit.