Kelly Bailey

Kelly Bailey was the senior game designer of sound and music at Valve Software, conceptual artist and the composer of the Half-Life series music.

Kelly Bailey has a background as a singer, songwriter and guitarist for local bands in Seattle, Washington. He was a product unit manager at Microsoft and he has a background in programming that encompasses consumer multimedia, database engines and networking. At Valve Software, he initially worked full time on engineering. After submitting a five-song demo CD to the company, he was put in charge of the music and sound effects for the 1998 Valve first-person shooter smash Half-Life. He also wrote the code that allowed the Half-Life characters to speak and implemented the software DSP system that provides reverb and echo effects. Kelly Bailey is also the lead singer for a Seattle band Lucy's Fishing Trip.

Around March 2011, Kelly Bailey left Valve with colleague Mike Dussault to work on their project Sunspark Labs LLC, launched in December 2010, developing iOS applications, their first being "Morfo", released in June 2011.