On August 21, 2018, Valve announced a new version of Steam Play for Linux gamers called Proton. This feature is a fork of Wine, a compatibility layer that allows Windows applications to be run on Linux operating systems. In addition, it runs on the DXVK and VKD3D wrappers which translates DirectX 11 and DirectX 12, respectively, to Vulkan.
What Proton Brings to the Table
Proton brings several improvements to the Linux gaming experience. The biggest improvement, arguably, is the expansion of the list of games playable on Linux. Prior to the Proton announcement, less than a quarter of the entire Steam library has native Linux support. With the implementation of Proton, the entire library is theoretically accessible on the Linux steam client albeit with worse performance and compatibility issues on certain games.
The feature also brings more convenience to the Linux user. Previously, if Linux gamers wanted to run Windows-only games from Steam, they had to install the Windows Steam client which is separate from the Linux Steam client. In addition, on August 24, 2018, Valve rolled out Steam Play into the stable Linux Steam client. Prior to this announcement, the user had to opt into the beta version of the client which is an extra step towards activating Proton.
Proton’s Impact on Linux Gaming thus far
Upon the initial announcement, there was clear enthusiasm for Valve’s proton initiative. For instance, the viewership of the article on the GamingOnLinux website is greater than that of the average article. Forum participation on Phoronix topped out at 179 comments which is much higher than the average amount of comments per article. The dedicated Proton thread on ResetERA has exceeded 1400 comments and is still somewhat active.
This enthusiasm has translated into deep engagement from the open-source community in improving Proton. Many Linux gamers still submit issues to the Proton GitHub page. They also send whitelist requests and even code to help improve the project. The community put together a very large Google Doc which lists how each game works on a particular CPU/GPU configuration. Considering how large the document is, the work was eventually put towards a more user-friendly website.
Six days after Valve’s announcement of Steam Play Proton, 971 unique titles were labeled as completely stable on top of the 27 already white-listed games, according to Forbes. Theoretically, as Proton, DXVK, and VKD3D continue to improve, the list of perfectly compatible titles should grow.
Lastly, Proton appears to have increased Linux’s Steam marketshare. On September 3, 2018, Valve released its Steam Survey results for August 2018. Linux marketshare rose from 0.49% in July to 0.59% last month. This is the highest marketshare Linux has had on Steam since September 2017 at 0.60%. It remains to be seen if Linux adoption continues to rise after Proton has a full calendar month.
The reception of Steam Play Proton appears to be positive as suggested by an increase of enthusiasm for Linux gaming online and Linux Steam marketshare. While this is an encouraging sign, it should be noted that Proton has only been available for 2 weeks.
Considering how large Steam’s library is, there is still a lot of testing to be done before the project can be considered a success. There are several Linux distros and desktop environments (e.g. GNOME, Xfce, KDE, Cinnamon, MATE, Budgie, etc.). On top of that, there are even more different CPU/GPU configurations. For example, performance and compatibility of a game on an AMD build may be significantly different from an Intel/Nvidia build. As a result, Valve and the open-source community’s engagement need to be maintained for the longterm.