[3][4] Prior to becoming chief technology officer at Shopify, Lemieux was the Senior Vice President of Engineering after joining the company in 2015.
Before working at Shopify, Lemieux was Vice President of Engineering at Atlassian and Chief Architect for Rational Team Concert.
[3] Lemieux holds two patents in the field of software configuration management and is the co-author of the book Eclipse Rich Client Platform.
[5][6] In 2020, Lemieux created a COVID response fund in his home town of Ottawa to help local non-profits during the pandemic.
Lemieux is the owner and sole investor in Arlo, a Ottawa restaurant specializing in natural wine and refined food in a quirky and casual setting.