Apple has upgraded its Swift programming language, promising developers improved stability, performance and some useful new features.

Swift was unveiled by Apple in June as a successor to Objective-C, and can be used to develop applications for iPhones, iPads and the company’s laptops and desktops. Apple designed Swift to be as easy to use as popular interpreted languages such as Python and JavaScript, while maintaining the speed and flexibility of compiled languages.

The new version of Swift has been improved on two fronts: the language itself and the compiler it comes with, Apple said in a blog post on Monday.

The new compiler is more stable and offers improved performance in every way, Apple said. The most common compiler crashes have been fixed and there are also clearer error and warning messages.

The language has been further refined to be more predictable and offer better interaction with Objective-C. That’s important because the two languages can be used side-by-side when building an app.

The upgrade is called Swift 1.2, and is part of a new beta of Apple’s IDE (integrated development environment), Xcode, which has been christened version 6.3.

To help developers get started with Swift, Apple has published a wealth of information on the languages-resource page. Prospective users can find a set of set of programming guides, sample code and videos on topics such as integrating Swift with Objective-C. Apple is working with the likes of Stanford University; the company also offers courses via iTunes U.