In 2011, Moose joined Bon Iver. He contributed musical arrangements and recorded strings for the group's self-titled second album, "Bon Iver" (2011). The album was certified platinum by the Recording Industry Association of America (RIAA) in 2019. The album won Best Alternative Music Album at the 2012 Grammy Awards, while the band won Best New Artist for their work on it. Moose toured with Bon Iver, including performing four sold-out concerts at Radio City Music Hall and an appearance on "Saturday Night Live". Bon Iver's third studio album, "22, A Million" (2016), featured Moose's violin and viola arrangements on "22 (OVER S∞∞N)" and saxophone arrangements by Moose throughout. Moose contributed to the band's fourth studio album, "I, I" (2019). Moose contributed violin, viola, octave viola, piano, string arrangements, and all "Worm Crew" arrangements. He served as the "Worm Crew" conductor. Moose has songwriting credits on "iMi", "Holyfields,", and "Marion".