"Anexo3" was composed in 2017-2018 over residencies in Bilbao, Lima, and Santiago de Chile, through elaborated processes of sound design, experimentation, improvisation, recording, and reflection. Often processed beyond recognition, violin, flutes, and saxophones along güiros, motors and an aluminum plates system, struck and induced into resonance through feedback processes controlled by microphones, transducers, and computer software and joined by Oliver's MANO computer-based instrument. The sonic world of Anexo3 ranges from metallic sonorities of the instruments and the industrialized cities we work in, the feedback systems we inhabit, and soundscapes of imaginary nature. A forty minute structured improvisation, Anexo3 is partially notated with traditional music notation, graphic notation, text indications, and inscriptions on the instruments themselves. The work is also heavily encoded in a software that shapes the ensemble's sound and the set of actions the musicians must make to control the temporal evolution of the piece.