After graduating from Glasgow University with a first-class law degree,[4] he put together his demo album Home Tapes in 4 days on an 8-track recording machine.

Released as a limited edition pressing through small Glasgow indie label Adorno Records, the demos subsequently sold out, and led to an invitation to open for Kris Kristofferson.

[5] Hart then began recording his solo debut studio album Bookmarks, with members of Scottish band the Trashcan Sinatras with whom he had been touring at the time.

This in turn led to an invitation to perform the Burns poem "Nature's Law" for the Queen at the Scottish Parliament on 4 July 2009, to mark its 10-year anniversary.

Hart then formed The Lonesome Fire with other members of the Scottish music scene, and worked with Patti Smith and Morrissey producer Danton Supple.

From the 24–28 February the band performed a song each night from the album – Queenstown, Cold City Avalanche, High Hopes, Forget Me Not and Bad Blood – on shows that featured guests including Zooey Deschanel, Ashton Kutcher, Vera Farmiga and Alice Eve.

[7] The concert featured Rosanne Cash, Josh Rouse, Thea Gilmore, Gemma Hayes, James Grant, Tim O'Brien, Kris Drever, Rab Noakes, Laura Cantrell, Eddi Reader and Tommy Reilly, with The Lonesome Fire performing and acting as house band for the evening.

Hart now curates the Roaming Roots Revue each year at the Glasgow Royal Concert Hall for Celtic Connections, which focuses on new and unusual collaborations between a transatlantic-spanning array of musicians performing their own material and that of something from a themed songbook.

The shows have featured artists such as Kris Kristofferson, Jesca Hoop, Frazey Ford, Matthew E. White, Field Music, Justin Currie, The Pierces, Howe Gelb, Roberta Sa, Beth Orton, The Low Anthem, LAU, Gemma Hayes, Dawes, Lindi Ortega, Rachel Sermanni, Roddy Woomble, Grant Lee Phillips, Dawn Landes, KT Tunstall, The Staves and many more.

[13] He succeeded Edith Bowman as presenter of The Quay Sessions in 2016, and now hosts the live music show for TV and radio each Wednesday night.