Performance of the Dark Energy Spectroscopic Instrument (DESI) fiber system

The recently commissioned Dark Energy Spectroscopic Instrument (DESI) will measure the expansion history of the universe using the Baryon Acoustic Oscillation technique. The spectra of 35 million galaxies and quasars over 14000 sq deg will be measured during the life of the experiment. A new prime focus corrector for the KPNO Mayall telescope delivers light to 5000 fiber optic positioners. The fibers in turn feed ten broad-band spectrographs. We describe key aspects and lessons learned from the development, delivery and installation of the fiber system at the Mayall telescope.