The company expects to hire another 400 people in 2022. Wallen started Hotel Engine in 2015 as a “simple” booking tool designed to support the hotel lodging needs of clients of another company he’d founded, Travelers Haven. Ramzi Ramsey, managing director at Blackstone, believes that Hotel Engine provides “a unique and differentiated” experience, especially for industries that have historically been underserved by traditional travel booking companies that do not specialize in group or long-term stays. Hotel Engine is the latest such startup, having just raised $65 million in a Series B round at a $1.3 billion valuation. For the first two years, Hotel Engine was more of a side project for Wallen with admittedly “limited investment or attention.” And notably, Hotel Engine is something that many startups are not: profitable. Wallen believes Hotel Engine is unique in the way that it leverages technology to connect businesses and lodging partners globally. “Our approach allows our customers the ability to centralize their lodging needs on one platform from sourcing and negotiation to booking and reconciliation,” he said.