In 2005 Egan spent a short four months as a product manager at Microsoft and shortly afterwards he acted as a consultant for Exeter Group. He spent three years as cross functional lead at Harvard University before starting his own venture, Caffeinated Mind, Inc. The company was eventually acquired by Facebook and two years later Egan was hired at Facebook as product manager in information and recruiting tools. During his time in that role he optimized communication and distribution of information within the organization and created Facebook's custom sourcing system which allowed them to rapidly grow to 20,000+ employees. 
In 2014 Egan stepped up as product lead and cofounder of widely adopted Workplace by Facebook where he helmed the London-based product team and managed all efforts to make workplaces more connected with Facebook. In 2016 he went back to being product manager at Facebook and eventually left the company in October of 2017.