Valve adds experimental Arm support to SteamOS in latest Runtime update — Deckard may launch soon

We have reported numerous times that Valve seems to be planning to introduce Arm support to its Linux-based SteamOS operating system, but the first bit of actual code has shown up in the SteamOS GitLab repository proving this to be the case.

As spotted by SadleyItsBradley on X, the latest Steam Runtime code commit mentions an experimental version of the Steam runtime for the 64-but arm64 architecture. This is clearly still a work-in-progress, but it looks like Valve is slowly putting developer resources behind adding Arm support to SteamOS. 
 

There is also an experimental version of the runtime for `arm64`(64-bit ARM, also known as `aarch64`).
This does not provide a secondary architecture, which means that 32-bit ARM binaries are not supported.
 

Previously, speculation suggested that Arm support would be added to SteamOS in anticipation of the launch of the long-awaited Valve Deckard standalone VR headset, but one of the consequences of Arm support would be support for devices like the recent Snapdragon-powered Windows on Arm devices, like the Microsoft Surface Laptop 7 (curr. $799.99 at Best Buy). Another potential theory is that Valve was scoping out Arm support for a potential Nvidia-powered Steam Deck 2. 

It's widely known that Apple used Wine — the open-source base for Steam's Proton compatibility layer for Linux — to build its Game Porting Toolkit, which enabled running Windows games on Apple silicon-powered macOS devices. Thus, it stands to reason that Valve could arguably do the same thing for Arm hardware as it continues to develop the experimental Arm64 support. 

Valve was also previously caught testing arm64 compatibility for a number of games, including a number of non-VR titles. Taking all the evidence together, it seems as though the intention is to simply expand the availability of SteamOS compatible hardware to Arm devices in addition to the current crop of x86 hardware.