Shaffelburg played youth soccer for Valley United SC and Team Nova Scotia.

[4] Shaffelburg demonstrated dominance in cross country running and track and field in his middle school years.

[11] He had originally committed to the University of Virginia on a soccer scholarship, but ultimately decided to sign a professional contract instead.

[13] In November 2018, he signed his first professional contract with Toronto FC II[9] and began the 2019 season with them in USL League One.

[8] He made his first MLS appearance the following day, playing 31 minutes against FC Dallas in Frisco, Texas.

[17] Shaffelburg would quickly find himself in the starting lineup shortly after signing, earning rave reviews for his pace from the coaching staff.

[22] In August 2022, Shaffelburg joined Nashville SC on loan for the remainder of the 2022 season, with an option for a permanent transfer in 2023.

[25][26] Shaffelburg was named to the Canadian U-23 provisional roster for the 2020 CONCACAF Men's Olympic Qualifying Championship on February 26, 2020.