Apple made the source code of Grand Central Dispatch available under an Apache open source license. One of the new technologies for concurrency added to Mac OS X 10.6 Snow Leopard, Grand Central is Apple’s attempt to help developers deal with the rise of multi-core. The open sourcing of Grand Central comes as something of a surprise, because it is a core technology in Snow Leopard, and could be seen to give Apple a competitive edge in the new world of multi-core… this is an exciting move, particularly for scientific developers. If Grand Central Dispatch does catch on, it could provide a genuine option for code parallelization on and off the Mac.