Sébastien Vaillancourt is a Basel-based composer-performer and sound artist whose practice centers on transduction: using electronics and sensing to translate physical gestures into sound and light, and in doing so, to reveal aspects of the world that might otherwise remain imperceptible. Working across acoustic and electronic media, he creates performances and interactive systems in which plants, antennas, motion sensors used on the body, and other unconventional interfaces become instruments. His live-electronics practice explores how these technologies can extend perception, drawing attention to subtle relationships between bodies, materials, and environments.

His work has been commissioned by Ensemble Proton Bern, the Akademie der Künste Berlin, Klangwerkstatt Berlin, the Max Steiner Ensemble Vienna, and solo performers such as Jeanne Larouturou and Malin Sieberns. He has performed solo and in collaborative contexts at festivals such as Maerzmusik (Berlin), KONTAKTE (Berlin), Mise-En (New York), Decibels (Riga), and the Röstibrücke Electroacoustic Cabaret (Geneva). He has also designed live-electronics systems for productions at the Münchner Biennale, Donaueschinger Musiktage, ECLAT Festival Stuttgart, Wittener Tage für neue Kammermusik, and Maerzmusik, collaborating with composers and performers including Thomas Kessler, Luxa Martin Schüttler, Anda Kryeziu, and Håkon Stene.

He has taught live electronics and programming in higher-education music institutions. He studied at the Hochschule für Musik Hanns Eisler Berlin and the Université de Montréal, has been supported by Pro Helvetia, and was an artist-in-residence with the Mise-En Ensemble in New York. He has released two albums, with a third forthcoming in 2027.