Comedian Bill Hader kicked off today’s Apple Worldwide Developer Conference (WWDC) in an opening video of him preparing for the conference. While he wasn’t able to give us the musical number, dancing apps or high-flying trapeze acts he planned for, he did leave with one note: “Whoever walks out there better have something pretty incredible to say,” and Apple tried not to disappoint.

The conference covered OS X, iOS 9 and even a new streaming music service. But for developers the biggest news featured the company’s Swift programming language and the recently launched Apple Watch.

(Related: How Apple Watch is boosting wearables)

Announced at last year’s WWDC, Swift is making its way to the open-source community, according to Apple. “We think Swift should be everywhere and used by everyone,” said Craig Federighi, senior vice president of software engineering at Apple. The company will be rolling out the compiler and standard libraries for iOS, OS X and Linux, and it is expected to be open-sourced by the end of the year.

The programming language will also be getting a major update in Swift 2, which will include new optimization technology, an error-handling model, synthesized headers in Xcode, and new APIs and protocol extensions, according to Federighi. “We think Swift is the next big programming language, the one that we will all be doing application and system programming on for 20 years to come,” he said.

It has only be six weeks since Apple made the Apple Watch available, but already the company is looking ahead to the next version of it. watchOS 2 is trying to make the Apple Watch a game-changer with new development features. Kevin Lynch, vice president of technology at Apple, took the stage to announce the new capacities and features that third-party developers will be able to take advantage of.

With watchOS 2, developers will be able to bring native apps to a user’s wrist, allowing all the logic from those apps to run locally on the watch. According to Lynch, this will improve app performance and responsiveness.