Not just Proton: Getting to know Valve's new SteamOS compatibility layers

Valve is expanding its SteamOS compatibility toolkit beyond the well-known Proton layer. To support the Steam Frame and improve performance on Arm-based chipsets, Valve has integrated FEX, an open-source project that emulates x86 processor instructions. FEX functions as an advanced binary recompiler, allowing Windows-based software to run on non-x86 hardware by translating instructions and interfacing directly with graphics APIs like Vulkan and OpenGL. This development is the result of years of funding and collaboration between Valve and FEX lead developer Ryan Houdek. By utilizing code caching and minimizing overhead, Valve aims to ensure that its gaming ecosystem remains robust and performant across diverse hardware architectures. This strategic move signals Valve's long-term commitment to decoupling SteamOS from traditional x86 dependencies, potentially paving the way for a broader range of portable gaming devices in the future.