J. Mordechai is the alias of Brooklyn-based artist and producer Jordan Rapaport. Working across club music, composition, and collaboration since 2016, he released his debut EP Reveries in 2023.

His 2025 single "My Lyre," featured in Resident Advisor's Best New Music, is the first taste of his forthcoming album Spectres — "pitched-up vocals threading through nocturnal garage and weighty dubstep, sleek and tunneling but lit from within."

Beyond his solo work, Rapaport co-produces, scores for dance and theater, and performs live across New York's underground. He is a permanent member of Aisle Knot and has supported the live performances of keiyaa, Beshken, Crosslegged, and others.