Chris Lattner, Apple’s senior director of its developer tools department, said Tuesday that he is leaving Apple to “pursue an opportunity in another space.”

Lattner spearheaded the creation of Apple’s Swift programming language, which the consumer technology giant debuted in 2014 as its de-facto language for third-party developers to build apps.

Ted Kremenek, a current Apple (AAPL) senior manager, will take over as leader of Apple’s Swift programming language and related development, Lattner wrote in an email to Swift users.

“This decision wasn’t made lightly, and I want you all to know that I’m still completely committed to Swift,” Lattner wrote. “I plan to remain an active member of the Swift Core Team, as well as a contributor to the swift-evolution mailing list.”

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Apple’s Swift language was developed to replace Apple’s older programming language Objective-C as the company’s preferred way for third-party coders to write software for its devices like the iPhone and the MacBook.

Many coders outside of Apple praised the Swift language for its simplicity compared to its predecessor. Companies like ride-sharing startup Lyft and IBM (IBM) incorporated the language into their own services.

In December 2015, Apple made the Swift language available to coders to use for free in what’s known as an open-source model. Compared to other technology giants like Facebook (FB) and Google (GOOG), Apple has generally been quieter about advocating for open-source technologies.

In recent years, however, Apple has made public its use of open-source technologies to run its popular services like the Siri digital assistant, likely as a way to court developers and show the company is on top of the latest coding trends.

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Chris Wanstrath, CEO of the online coding repository startup GitHub, recently commended Apple for open sourcing the Swift language and said that Apple’s culture, like Microsoft’s, is changing to accommodate open-source tech.