@previous (C)
Syntax got a cameo in the film for advising Spielberg on cutting edge special effects back in 1975. Not a lot of people know this, but Syntax actually designed the waterproof animatronics for the shark. In several scenes where you just see the dorsal fin cutting through the water, that's actually Syntax swimming while holding a cardboard fin cutout. He also operated the shark controls during the scene where Quint gets eaten.
Ultimately Syntax and Spielberg ended up parting ways after the second film because of Spielberg's insistence on filming on Tuesday nights.