Born in Lausanne[1] to a professional hockey player father, Bastian wanted to become a professional hockey player in the footsteps of his father and played on Swiss National League's Juniors Elite A side "Lausanne 4 Clubs" under the name Bastien Kaltenbacher.

[2] But interested in music as well, he joined the school choir in Villeneuve, and was given solo roles.

Baker was the opening act for all dates of Shania Twain's 2018 Now Tour and performed "Party for Two" with her during her set.

On 20 August 2020, Baker was officially signed to a one-year contract by third-tier ice hockey team HCV Martigny of the MySports League and was introduced to the media at a press conference that same day.

Baker was born to hockey player Bruno Kaltenbacher and school teacher Magali, and has two sisters, Margaux and Marine.