Goss joined McLaren in 1990, becoming the engineer in charge of engine installation design. He was then appointed assistant race engineer to Mika Häkkinen, and then became chief test team engineer. After working as head of vehicle dynamics, he then worked as chief powertrain engineer, which saw him oversee the introduction of F1's first seamless-shift gearbox in 2005.
In 2005 he was appointed Chief Engineer for the McLaren MP4-21 and led the engineering design team of the Adrian Newey designed 2006 car. After a few races it soon became clear that it was not as competitive as its predecessor, the MP4-20, despite an apparent improvement in reliability. McLaren did not win a race all season, for the first time since 1996.
Goss was appointed Director of Engineering in January 2011. In February 2013, after McLaren confirmed the departure of Paddy Lowe to Mercedes F1 effective for the 2014 season, Goss was appointed Technical Director. He held the position of technical director until 2018 when he was removed from that post.