Hyundai Engineering & Construction (Hyundai E&C) is a major South Korean construction and engineering contractor that builds nuclear plants. It is Holtec's construction partner for the SMR-300 and, on 30 October 2026, signed a five-year master service agreement with First American Nuclear (FANCO) for constructability review, technical design advice and construction feedback on the EAGL-1 fast reactor. It is a separate company from Hyundai Engineering.