According to The Verge, Valve’s Pierre-Loup Griffais has revealed the company has been secretly funding the open-source technology needed to run Windows PC games on Arm-based devices since 2016 and 2017. This includes almost all the work on a compatibility layer called Fex, which lead developer Ryan Houdek prototyped in 2018 and now works on full-time thanks to Valve’s support. The tech stack, which also includes the Proton compatibility layer, is what allows the newly announced Steam Frame VR headset to play Windows games, and it’s already enabling games like Hollow Knight: Silksong to run on a Samsung Galaxy S25. Valve’s goal is to create a future where PC games can run on any Arm device—phones, laptops, desktops—without developers needing to do arduous ports. The company believes this will break down arbitrary barriers and expand PC gaming to new form factors and power segments where Arm chips excel.
The Trojan Horse Strategy
Here’s the thing about Valve: they rarely do the obvious thing. They don’t just build a phone and hope people use it. Instead, they build the foundational plumbing for an entire ecosystem and let others—or their own later hardware—ride on top of it. The Steam Deck wasn’t just a handheld; it was the vehicle to prove a decade of Linux investment could work. The Steam Frame VR headset? It’s not just VR. It’s the first major hardware showcase for their Arm-on-Windows translation tech.
And it’s a brilliant, capital-E Efficient strategy. By funding open-source projects like Fex and contributing heavily to Wine (which forms the core of Proton), Valve isn’t on the hook for all the development. They’re shepherding it. They’re paying key developers to “follow their passions,” as Griffais says, toward a goal Valve set. The tech gets built, it’s open for anyone to use, and Valve’s hardware division can then swoop in and build the most polished consumer-facing product using that now-mature stack. They de-risked everything.
Why This Is A Big Deal
Look, the dream has always been “buy a game once, play it anywhere.” But between x86 PCs, Arm Macs, iOS, and Android, it’s been a fragmentation nightmare. Ports are expensive and take forever. Valve is basically trying to brute-force a solution through software emulation and compatibility layers. If they get it right, the architecture of your device becomes irrelevant.
Griffais is candid about the motive: in low-power segments below the Steam Deck’s wattage, Arm chips are often just better. More efficient. Cheaper. Imagine a $199 handheld that can play your entire Steam library, or a phone that turns into a serious gaming device with a controller clip. That’s the potential. It also paves the way for Arm-based gaming laptops and even desktops, especially as companies like Qualcomm and Apple push high-performance Arm designs. Valve is future-proofing Steam against a possible architectural shift in the broader PC industry.
So, Will There Be A Steam Phone?
Maybe. But probably not in the way you think. Valve’s modus operandi suggests they’ll get SteamOS for Arm running smoothly, partner with a few OEMs to make “SteamOS-certified” phones or handhelds, and see what sticks. They’re already having those conversations for living room devices (Steam Machine 2.0, anyone?) and handhelds. The OS is ready. As Griffais notes, it’s the same Arch Linux base; it just downloads an “Arm-aware” Proton with Fex built-in.
The real question is performance. Emulation and translation always have a cost. But the fact that they’re demoing a 2025 AAA game like Silksong on a current-gen phone is promising. They’ve been working on this for nearly a decade because they knew it would take that long to be robust. This isn’t a side project. It’s a core, long-term bet.
The Bottom Line
Don’t judge this by the Steam Frame’s potential market success. Judge it by the infrastructure being laid. Valve is playing a 10-year game, quietly building the bridges between the massive library of x86 Windows games and the Arm-dominated future of personal computing. They’re not just making a VR headset or a console. They’re attempting to make the entire concept of “platform” irrelevant for PC gaming. If they succeed, the Steam Machine will indeed be a footnote—because the real story will be that your entire Steam library lives in your pocket, on a device Valve might not even have to build themselves. Now that’s a power move.
