This practice research engages with a need to scrutinise the affordances of mixed music for violin within a multi-agent situation of a performance ecosystem. The affordances of chamber music with real-time sound processing and fixed media situate the violinist within a larger performer-instrument-environment network. Performing mixed music repertoire requires a type of responsibility from the instrumental performer, through which the disparate components of sonic technologized environments are brought together, internalised, and embodied through an active agency of the violinist within a two-performer paradigm. As a starting point for analysis and as a reference for observation, a framework of the violining body is proposed to guide the direction of this research towards a continuous redefining of habitual customs away from a violin-centric approach. Situated in an expert violin practice from the outset, a continuous striving for renewal is embedded in the materiality of the electronic mise-en-place1. Specific attention is paid to issues of sound, interaction, and agency, with a pragmatic emphasis that privileges rehearsal and performance. Through a prism of eight contrasting case studies, a notion of an ecosystemic virtuosity is developed throughout the thesis, where elements of the practice are studied in their interrelation. By presenting a firsthand account of practice, this research contributes to illuminating the role of collaboration, development of a common vocabulary, and shared sonic environments in the making of an ecosystem. This research navigates the active agency of the violin sound as a means for engagement with electronic material. Through exploration of a wide spectrum of mixed music repertoire, this research seeks to distil patterns of practice that lead the violinist to becoming a better chamber musician situated in an ecosystemic context. This work is an account of wayfinding through the complexity of interactions, technologies, and embodied agencies enacted in the repertoire for violin and electronics from a point of view of a conservatoire-educated violinist, with the aim of creating a transferrable account of a scrutinised practice that can assist future researchers, performers, and composers.