Mack is a Stevedore for the Everett branch of UCAS Shipping International. This means his job mainly consists of monitoring drones that load and off-load cargo at piers F-J. While this is less dangerous than jobs stevedores performed in the past, the lack of real tech supervision on the docks and the age of the drones involved often means that injuries are far more common than typical watchmen details.
Mack had an arm crushed underneath shipping container about three years ago and went to Cheonji after being denied compensation by UCASIS health care. There Mala was able to magically regrow most of his upper arm, making the cybernetics for his missing forearm and hand much less invasive. They have kept in contact ever since and Mala frequently counts other stevedores among her patients.