Valve announced today a beta of Steam Play, a new compatibility layer for Linux, to provide compatibility with a wide range of Windows-only games.

We've been tracking Valve's efforts to boost Linux gaming for a number of years. As of a few months ago, things seemed to have gone very quiet, with Valve removing SteamOS systems from its store. Last week, however, it became clear that something was afoot for Linux gaming.

The announcement today spells out in full what the company has developed. At its heart is a customized, modified version of the WINE Windows-on-Linux compatibility layer named Proton. Compatibility with Direct3D graphics is provided by vkd3d, an implementation of Direct3D 12 that uses Vulkan for high performance, and DXVK, a Vulkan implementation of Direct3D 11.

To improve the broader gaming experience, Valve says that fullscreen graphics, multithreading, and gamepad support have all received attention.

Once Steam Play is out of beta, developers of Windows games will be able to mark their games as being Steam Play compatible and, hence, will be offered for sale to Linux users. Valve has already tested and validated more than two dozen traditional and VR games, including Doom (the original, 2016, and 2017-in-VR flavors), NieR: Automata, and Quake. While support for other games is being worked on (which users can vote for here), Steam Play testers can toggle an override switch to test any games that Valve has not internally whitelisted thus far.