This research is a practice-led investigation into collaborative user interfaces within the practice of live coding; the act of writing computer code for generating improvised music live in front of an audience. It examines the impact of user interface design parameters on group creativity and explores the roles of data, text, and programming languages as media for musical communication. Utilising a multi-faceted research method that combines iterative “participatory design” (Spinuzzi, 2005) with performance-led “research in the wild” (Benford et al., 2013), this research couples ethnographic and autoethnographic observations to gain insight into the practice of ensemble live coding and inform software design. Three novel collaborative interfaces have been developed as part of this research that explore various facets of musical collaboration in live coding. Each interface was developed through an iterative and reflexive methodology focused on user-centred design and was employed in a cyclical process of artistic practice and refinement based on user evaluation and in-depth study. The first interface, entitled Troop, is a shared text editor that allows multiple performers to collaborate on the same single body of code together. The second, CodeBank, explores how private working in a collaborative context affects creativity and improvisation. Finally, PolyGlot, combines multiple live coding languages into a single collaborative interface that enables live coding musicians to play together, regardless of their knowledge of languages. As well as these three graphical interfaces, the functionality of an existing live coding language, FoxDot, was extended to help facilitate the sharing of musical information within an ensemble. Each interface was used in live performance by The Yorkshire Programming Ensemble and evaluated through group interview sessions that examined the themes of immediacy, trust, and risk with regards to both human-computer interaction and intra-ensemble communication as well as the experience of personal- and group-flow states
