Mr. Colin Finck on behalf of ReactOS project has announced the release of ReactOS 0.4.9. It is the latest stable release in ReactOS tri-monthly release series.

The ReactOS tri-monthly release series has reduced the number of changes in each cycle. Rather, it provides improved workflow and ensures the work is moving in the right way.

What is ReactOS?

ReactOS is an independently developed, windows binary compatible operating system. It provides a traditional user experience to make users more productive while moving from other platforms. Despite the default look and feel resembling Windows 9.x releases, ReactOS supports most of the modern windows applications. The project also reuses some components from open source project’s like Wine to avoid reinventing the wheel from scratch.

What is new in ReactOS 0.4.9?

The main highlights of ReactOS 0.4.9 include improved stability and usability improvements.

• ReactOS 0.4.9 is a self-hosting operating system. It means, the ReactOS code can be compiled on ReactOS itself. It is a big deal, due to the complexity involved in handling memory and IO cycles. In past, ReactOS used to be a self-hosting operating system. This capability was lost while migrating the Kernel to be compatible with NT components.
• A major source of system instability came from the complex interplay between the memory manager, the common cache, the hardware abstraction layer (HAL), and the FastFAT driver. The biggest culprit in the instability came from the significant resource leakages caused by the FastFAT driver, resulting in it eating up the common cache to the point where attempts to copy large files would result in a crash. Multiple stability related issues have been rectified in ReactOS 0.4.9.
• Ability to handle zip files natively. Now, you can handle zip files in ReactOS without installing any 3rd party applications.
• Ability to choose between copy, cut and create link while dragging files from one location to another.
• There are of course plenty of other changes in less trodden parts of ReactOS, with many people providing contributions and improvements. These range from the functional, like zooming no longer crashing in the Paint application thanks to Stanislav Motylkov, to more behind the scenes like Timo Kreuzer’s continued efforts to prepare the codebase to actually function when building an x64 target (the project owes Timo many bottles of beer for taking on that one).
• And other improvements…

For a complete list of changes and screenshots, see ReactOS 0.4.9 release announcement.