Doppelganger was commissioned by Kwartludium ensemble and had its premiere during Unsound Festival in 2019, in Cracow. For this project, Ryterski constructed 3 different robots, or - being much more specific - 3 machines, which perform the music. First one is an automated pianist, second is an automated string instrument, and the last one is an automated percussion percussionist. There is also an additional clarinet, with a speaker put into its bell and a microphone at the other end (the instrument was without a mouthpiece). Doppelganger deals with the problem of mechanization, machine learning and using algorithmic tools during the process of composition - the real acoustic instruments seem to be competing with their mechanized substitutes.