When Trip.com Group released its financial numbers on Thursday, analysts understandably focused on details about consumer buying patterns and forecasts about border restrictions lifting, the company’s partnerships with destination marketing organizations, and management forecasts for revenue and profit.

But for European airline executives, an equally interesting story has been how the online travel conglomerate has been using its technology stack, particularly its flight search engine, to become a worthwhile channel for distributing tickets and ancillary products, such as extra legroom.

“Our flight search engine is completely designed and implemented in-house,” said Yudong Tan, CEO of the Flight Business Group, Trip.com Group, in an interview. “It has been at the core of our competitiveness in our flight business at Ctrip and Trip.com.”

Trip.com’s market share in the European market has increased by nearly five times since the start of the year, Tan told attendees at a company event in Macau earlier this month.

Trip.com’s behind-the-scenes software appears to have played a significant role in this market share gain, given that the company’s overseas paid marketing expenditures have been relatively modest this year.