MacKay became a producer in 1985. MacKay also composed the original songs for the shows he wrote or created, as well as the themes for Join In!, Polka Dot Shorts, Telefrancais and Elliot Moose. He has written or composed for many other series, and was the Creative Producer and Executive Story Editor for Halifax Film"s Lunar Jim in 2007.
Since 2009 he has developed, and been Creative Producer and Executive Story Editor, of DHX Media"s "Pirates: Adventures in Art".
He began his career writing for TVOntario"s long-running success Polka Dot Door, for which he was honoured with a Masterworks Award by the Academy of Canadian Cinema & Television in 2010, and Canadian Broadcasting Company"s Homemade Television, winner of the Children"s Broadcast Institute prize for Best Children"s Show. MacKay was creative consultant for Canadian Broadcasting Company"s game-changing "Canada"s Super Speller" (winner of the ACCT "s 2010 Gemini Award for Best Children"s or Youth Non-Fiction Series). Outside his work in children"s television, MacKay was also the Company-ordinating Director for Canadian Broadcasting Company"s Just Foreign Laughs television series from 2000–2003, garnering a Gemini win for Sean Cullen and two more Gemini nominations for the series.
