The Cocotron is an open source project which aims to implement a cross-platform Objective-C API similar to that described by Apple Inc.'s Cocoa documentation. This includes the AppKit, Foundation, Objective-C runtime and support APIs such as CoreGraphics and CoreFoundation.

Cocotron Info
Christopher Lloyd <cjwl AT objc DOT net>

Founder of The Cocotron project and primary contributor

David Young <daver AT geeks DOT org>
Dave was a big help giving the project a jump start at various stages, he wrote a prototype Objective-C runtime for Windows, later ported the runtime to Linux and Solaris, laid down a lot of classes not limited to: NSDate, NSCalendarDate, NSDateFormatter, NSNumberFormatter, NSTimeZone, NSTableView, NSOutlineView, NSScanner, NSDrawer, NSUndoManager, NSToolbar, NSRulerView et al, NSSlider*, NSSteppper*, NSBrowser*, tool tips, key binding, sheet/drawer animation, prototype NSMenuView, the Color panel, and their supporting classes. The Posix, Linux and Solaris classes as well as a bunch of build tools and makefiles prior to the CDT. Cocotron would not be what it is today without David's contribution.