UPDATED 12:06 22nd August 2015
The tricky forward signed for the Town from Northern Ireland Premiership side, Glentoran.
Stewart has represented Northern Ireland at Under-19 level and has been part of the Under-21 squad.
Made his debut at Millwall in October 2015 and spent a portion of last term on loan at Grimsby Town. Netted his first Swindon goal in the EFL Cup tie at QPR in August.