Before starting as a Screenwriter in 2008, Dubuque worked as a recruitment headhunter. He was approached by Producer Mark Williams with the rough idea for The Accountant, which Dubuque developed into a script named to the 2011 Black List of the best unproduced screenplays in Hollywood, including doing research to develop the protagonist (played by Ben Affleck) to have high-functioning autism; the film was credited by Autism Speaks for its portrayal of the disorder. The first screenplay of his to be produced, 2012's The Judge, led to Dubuque being recognized as one of Variety's 10 screenwriters to watch and named to the 2012 Black List with 20 mentions.

In 2015, Dubuque successfully pitched an action-adventure called The Real McCoy to Universal Pictures, with Chris Pratt attached to star; as of January 2018, the film is still in production. Another collaboration with Mark Williams, A Family Man, was released in 2016; with a working title of The Headhunter's Calling, the script was based on Dubuque's previous work in recruitment. Dubuque's teenage experiences at an Ozarks resort led him to work again with Producer Mark Williams and male lead Jason Bateman on developing the series Ozark, which was released on Netflix in 2017 and quickly renewed for a second season, as well as earning the writing team a Writers Guild of America Award nomination.