Airbnb Inc. is ramping up its investment in China, quadrupling its engineering team over the next 12 months to focus on affluent millennials who’re increasingly exploring the world’s second largest economy. Airbnb will grow its technical cohort to more than 100 in Beijing—the only office outside the U.S. where the home-sharing giant employs an engineering division, according to co-founder Nathan Blecharczyk. That move, part of a previously announced doubling in investment and tripling in local workers to 300, will help it tailor a re-launched service for some 400 million younger people acquiring a taste for independent travel, he added. “The most important thing is that we have an engineering team on the ground and local people in charge of the China business,” Blecharczyk, Airbnb’s chief strategy officer, said in an interview in Singapore Tuesday. “They understand their country the best. Even though we are a global technology platform, they have the technical ability to go and change things.” After years of feeling out the market, the world’s fourth-largest startup in 2017 appointed a Chinese chief and declared its intention to take on domestic market leaders such as Tujia and Xiaozhu. The company, which counts China’s sovereign wealth fund among its investors, is wooing a young middle class by adopting the moniker “Aibiying” (welcome each other with love), integrating local payment options and providing 24-7 customer support in Mandarin. But it’s adopting a strategy it deems more sustainable than local rivals that’re raising “unreal” amounts of cash and burning it quickly to drive growth “artificially,” Blecharczyk said. While it established a dedicated engineering team for China in the U.S. about three years ago, it relocated to Beijing at the end of 2016. Domestic travel within the nation now accounts for almost half of its business there, he said. It currently lists 100,000 homes, still well behind sector leaders such as Tujia. Airbnb however has handled more than 5.3 million guest arrivals by Chinese travelers at its listings around the world. Outbound travel from China—the world’s biggest source of international tourists—grew 142 percent in 2016. “Some might say we got off to a slow start in China, but if you look at how we’ve grown, it demonstrates a strong organic traction that I think is going to benefit us in the long term,” he said.