Another Twitter exec left the nest to hit the fast lane. Twitter’s senior director of engineering, Akash Garg, will be moving to ride-hailing company Uber, he announced via Twitter Tuesday.

Garg served in the position for more than four years, he noted in his announcement, and he oversaw Twitter’s growth and international team, as his Twitter bio noted. Interestingly, international expansion is one of the crucial markets and initiatives Uber has been pushing as it seeks to solidify its prominence in the ride-hailing industry.

Uber operates in 311 cities and 58 countries, the company reported in June. Yet, it’s still competing with other startups that were developed in competitor markets and the growing base in the United States. Just last week, news broke of San Francisco-based Lyft partnering with Didi Kuiadi, seen as Uber’s biggest rival in China. Didi Kuiadi was formed from a merger of Didi Dache and Kuaidi Dache in February 2015, and it now accounts for about 80 percent of the market share in China, Forbes reports.

Didi Kuaidi is backed by Alibaba and Tencent and is reportedly raising $1.5 billion in new funding, which would up its valuation to as high as $15 billion. That nowhere near compares to Uber’s valuation, which is about $51 billion as of July and has become the most valuable startup in the world. Money, power and the potential for growth isn’t hard to come by at Uber. That's one reason the company has attracted a slew of new recruits.

Taking advatange of both reach and technology may be one way the startup can compete. Indeed, Uber has made a number of acquisitions to improve its systems. In March, the company acquired map tech startup deCarta. In June, Uber purchased mapping tools from Microsoft’s Bing as well as about 100 engineers, the New York Times reported.

Garg, reportedly not the first engineer Uber has poached, will be leading the mobile and web platforms teams, he announced via Twitter. He has a track record of securing for Twitter lucrative partnerships from international competitors. For instance, in January Garg helped the microblogging site acquire ZipDial, a marketing systems company based in India, TechCrunch reports.

Business Insider referred to the loss of Garg as a Twitter “brain drain.” Several prominent executives have left the eight-year-old social network over the past few months. In August, Twitter’s former brand advertising manager, Nipoon Malhotra, left for product at Pinterest. In May, former Twitter director of corporate development and strategy, Jess Verrilli, left for Google Ventures.

That exodus coincides with the company’s stock facing some of its lowest numbers since its public offering in 2013 and a 100-day search, both inside and outside the company, for a new CEO.