Niall studied piano and composition at the Royal Irish Academy of Music. He was awarded first prize at the Dublin Film Festival's music score competition, chaired by composer Michael Nyman.
He has received several IFTA (Irish Film & Television Award) nominations and won Best Original Score at the 10th annual IFTA Awards for his orchestral score to the BBC film ‘Loving Miss Hatto’.
He has composed music for numerous international feature films, animation and many award-winning British television drama series including 'The Widower', 'Cilla' and the BAFTA-winning 'Little Boy Blue'.
More recent scores include the hit ITV drama series 'Manhunt', 'White House Farm' and 'A Confession' starring Martin Freeman (BAFTA nomination 2020, Best Mini Series)