Holfix (also known as DJ Holfix) is a YouTuber/musician who produces royalty free music for anyone to use. Many of the Yogscast members use his music in their videos. He has also created the music for the Yogscast song M.I.L.K..
In 2015, many Happy Chiptune remixes were made for Sips' videos, including ones for Fallout 4, Kerbal Space Program and Shoppe Keep.