Stewart started his career as a Cambridge mathematician and top-10 firm M&A investment banker before being seduced by music and deciding to formally study guitar. Two years later he gained the highest recorded postgraduate guitar mark in the history of the Royal Academy of Music, receiving the DipRAM alongside his colleague Milos Karadaglic.
During 2012-14 he toured as soloist with the Royal Philharmonic Orchestra, the highlight a sold-out concert at London's Royal Albert Hall. He has been broadcast repeatedly on BBC Radio and Classic FM, including a live broadcast on Radio3's Boxing Day breakfast show with Suzy Klein and James May. He has worked with most of the major classical labels, and has albums with Harmonia Mundi USA, Naxos and Draft. Collaborators include John Rutter, Tarik O'Regan, Paul Hillier, The Royal Philharmonic Orchestra, The National Chamber Choir, Dame Felicity Palmer, Iestyn Davies, CHROMA Ensemble, Jeremy Huw-Williams and Alan Clayton.
Alongside his work with CHROMA and the RPO he runs the recording research and consultancy firm mydraft.io.