Levi performed as a DJ in London, and released a mixtape titled Filthy Friends, which was posted on her official Myspace page. For Filthy Friends she enlisted the help of friends and musicians of various backgrounds including MCs Baker Trouble, Brother May, Man Like Me & Ghostpoet, singer-songwriter Jack Peñate, jazz band Troyka, London pop-band Golden Silvers as well as producers Kwes and Toddla T. Following its release, Filthy Friends became sought after on the London club scene.
While a student at Guildhall, Levi was commissioned to write an orchestral piece for the London Philharmonic Orchestra which was performed at the Royal Festival Hall in April 2008.
Levi was an Artist-in-Residence at the Southbank Centre in London in 2010.
Levi co-wrote and produced Tirzah's I'm Not Dancing EP, which was released by Greco-Roman Records in August 2013, to critical acclaim.Levi composed the soundtrack to Under the Skin, a film directed by Jonathan Glazer and starring Scarlett Johansson, released in 2014. The film is based upon the novel of the same name by Michel Faber. She was nominated for multiple Awards for this score and won Best Composer for this score at the 2014 European Film Awards, tying with Jonny Greenwood for Best Music/Score at the 2014 Los Angeles Film Critics Awards. She has also been nominated for the 2015 BAFTA Award for Best Film Music