Emily is a prolific composer and songwriter in a variety of genres.

Emily has been a Teaching Artist and composer with the Lullaby Project since its inception in 2011. This Carnegie Hall project pairs new and expecting parents with professional artists to write and sing personal lullabies for their babies, aiding childhood development, maternal health, and strengthening the bond between parent and child. In 2018, Decca Gold released an album of lullabies titled Hopes and Dreams: The Lullaby Project, and this album featured four of Emily's collaborations with new mothers, sung by Rihannon Giddens, Rosanne Cash, and Angélique Kidjo.

Commissioned by Carnegie Hall in collaboration with the Minnesota and San Francisco Operas, Emily co-composed Nooma, an opera for babies. Nooma premiered in 2019 at Carnegie Hall, with Emily singing a lead role.

Commissioned by Carnegie Hall's Weill Institute, Emily wrote a concert of children's songs that premiered in 2015.

Emily has composed works for several ensembles in which she also performs, including the trio Up at Dawn, which uses close harmonies to blend traditional sounds to new music. She has also composed works for Moving Star, a collaborative vocal lab based at Carnegie Hall.