[1][5] He began a master's program in American studies at Columbia University, but left to join Antony and the Johnsons on tour in 2005.

[8] He appeared on the Grammy Award-winning albums High Wide & Handsome: The Charlie Poole Project (2009) by Loudon Wainwright III and The Suburbs (2010) by Arcade Fire.

[11] Moose has worked as a music arranger for records by numerous artists including The Decemberists, Interpol, The National, St. Vincent, Bon Iver, Tune-Yards, LeAnn Rimes, They Might Be Giants, Trey Anastasio, Bruce Hornsby, Paul Simon, Sara Bareilles, Punch Brothers,[8][2] Phoebe Bridgers,[12] and Taylor Swift.

[13] His relationship with Blake Mills has resulted in collaborations on albums by John Legend, Alabama Shakes, Laura Marling, Jim James, Perfume Genius, Dawes and Jesca Hoop.

[8] Moose has also contributed arrangements to classical artists such as Joshua Bell and Renée Fleming,[8] and his work was featured on the Grammy Award-winning album High Wide & Handsome: The Charlie Poole Project (2009) by Loudon Wainwright III.

[2] Moose has also been a frequent contributor to Ben Folds' Declassified Series with the National Symphony Orchestra, writing charts for Sara Bareilles, Regina Spektor, Emily King and Blake Mills.

[18] He has worked as a conductor at numerous venues, including the Walt Disney Concert Hall and the Royal Opera House.

[16] Moose has toured with Antony and the Johnsons, Sufjan Stevens, The National, Beth Orton, Glen Hansard, and Blake Mills, and My Brightest Diamond.

[35] Moose toured with Bon Iver, including performing four sold-out concerts at Radio City Music Hall and an appearance on Saturday Night Live.