A finalist for the Male Paralympic Athlete of the Year, Farmer scored the game-winning goal in the gold-medal game against Canada at the 2015 International Paralympic Committee Sled Hockey World Championship in Buffalo, New York. He led the U.S. with six goals, tying the record for most goals scored by a U.S. player in a single world championship. He also set the Team USA record for most assists (6) and points (9) in a World Sled Hockey Challenge. Overall, he skated in 13 games for Team USA and finished as the team-leader in goals (10) and points (10-11-21).