A "guest composer" is a musician who is invited to create music for a specific event or project, but is not a permanent member of the group or organization they are composing for. Full definition
Various guest composers will be there including Christopher Tin (Civilization IV) and composers from both the Halo series and League of Legends. (thatvideogameblog.com)
MUSIC: 50th Annual Spring Conference on Wind and Percussion Music: Michael Markowski, Guest Composer Thursday, April 19, 7:30 p.m. Miller Auditorium, Free (wmich.edu)
confirm a handful of special guest composers and performers who will be on hand for the evening and those include: (originalsoundversion.com)