The 23-year-old former Partick Thistle and Morton player moves to the Kilmac Stadium at Dens Park on a two-year deal from Ayr United.
McPake told the club website: “He is a winger who can play off either side. I’m delighted to get him among interest from a lot of other clubs. From the conversations I’ve had with him I can see how ambitious he is. Like the club, he has a real drive to get back to the Premiership.”