Apple has released CarbonLib 1.5d4 SDK (Software Development Kit), the latest pre-release version of the kit for Apple's developer community.

It provides the files needed to begin Carbon development. The kit supports Mac OS 8.6 or later. Carbon APIs can be used to write Mac OS X applications that will also run on previous versions of Mac OS - from OS 8.1 or later.

Carbon is designed to provide a "gentle migration" path for developers moving from OS 9 to OS X. Carbon APIs are supported within OS 9, so developers can enhance applications for Mac OS X without ceasing support for customers using older operating systems.

The SDK is available for download to members of Apple's Developer Community (ADC).